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2-Stroke Cylinders to Crankshafts - Motorcycle Mechanics Institute

1. 81 and earlier front master cylinders should have some freeplay 82 and later do not 2 85 and earlier rear brake systems must freeplay F Front master cylinder 1 72 E 81 Lester has built in freeplay 2 L 83 and up Kelsey Hayes has no freeplay internals are held in place by a seal ring 5 bore sizes a 82 only had 3 4 bore b 83 95 had 5 8 bore on a single disc and 11 16 on a dual discs c 96 and up had 9 16 on singles and 13 16 on duals G Rear master cylinders 1 58 E 79 Wagner Lockheed cast iron a 58 E 72 hydraulic drum b 72 79 disc brakes 2 79 E 87 Kelsey Hayes aluminum requires a minimum of1 32 freeplay do not over torque 3 80 and up FLT FXR FXST used remote reservoir freeplay 1 32 4 cartridge type very rarely have to rebuild 5 L 87 and up built in freeplay replaceable cartridge H Hoses and lines 1 damage leaks and weather cracking 2 check for bulging or swelling when system is pressurized 3 replace any parts not in excellent condition I Calipers 1 damage leaks worn pivot points non stock parts 2 calipers must be free floating fasteners tight 3 pad condition correct parts damage wear uneven or less than 1 16 thickness tech 2 Tech 2 requires replacement a 1 2 pad thickness is better 4 half shim goes between piston and pad rotor must turn into cut in pad full shin goes between back
2. 1 A pie shaped segment of a spur or helical gear 2 Used in kick starter systems and shift linkages 5 Gear ratios NOVEMBER 9 10 1999 PAGE 4 A Numerical comparison of the number of revolutions of a drive gear to one revolution of a driven gear B Example 1 3 1 ratio means that as a drive gear makes 3 revolutions driven gear will make 1 revolution C Service manuals generally express gear ratios with the first number rounded to the thousandths 1 Example 3 000 1 or 0 698 1 or 1 230 1 D Basic gear ratio formula number of teeth on driven gear divided by number of teeth on drive gear E Example 1 Driven gear 50 teeth Drive gear 25 teeth 50 divided by 25 2 GEAR RATIO 2 000 1 DRIVEN divided by DRIVE F Three categories of gear ratio 1 Under drive gear ratio that is numerically greater than 1 000 1 a Example 1 300 1 or 3 000 1 b Drive gear is smaller than the driven gear c Under drive will increase will increase torque but decrease RPM 2 Direct drive gear ratio numerically 1 000 1 a Drive gear is the same size as the driven gear b Direct drive will not change torque or RPM 3 Over drive gear ratio that is numerically less than 1 000 1 a Example 0 900 1 or 0 600 1 b Drive gear is larger than the driven gear NOVEMBER 9 10 1999 PAGE 5 c Over drive will increase RPM but decrease torque 6 Drive ratios are used on motorcycles A Primary drives e SEE FIGURE 6 5 1 Gear reduction
3. 11 12 What is a gear e A rotating lever How is gear speed measured e Measured in RPM What is the force behind a moving gear e Torque force distance from pivot List 5 ways a gear can be used purposes e To transmit power To change direction of rotation To increase torque which decreases RPM To increase RPM which decreases torque For timing Gear ratio can be defined as e Numerical comparison of the number of revolutions of a drive gear to one revolution of a driven gear What is the basic gear ratio formula e Number of teeth on driven gear number of teeth on drive gear An underdrive will have a ratio that is numerically e Greater than 1 1 A direct drive will have a ratio that is e 1 1 An overdrive will have a ratio that is numerically e Less than 1 1 What s the formula for determining that primary drive ratio e Number of teeth on clutch number of teeth on crankshaft What is the formula for determining the transmission gear ratio on most transmissions e Number of teeth on countershaft number of teeth on main shaft What is the formula for determining the final drive ratio on chain or belt driven motorcycles e Number of teeth on rear wheel number of teeth on transmission sprocket 13 14 15 16 17 18 19 20 21 What is the formula for determining the final drive ratio on a shaft final drive motorcycle e Number of teeth on ring gear number of t
4. a b c The force that induces the valence electrons to move NOT the movement itself Voltage Potential difference electrical equivalent of pressure difference Imbalance of electrical charge between 2 points Voltage difference between two points in an electrical circuit Created By heat friction chemicals magnietisim Continuity The ability of a component switch fuse wire etc to flow current Go No go Continuity is NOT a measurement the component is either continuous or it isn t Examples an open switch has no continuity a closed switch has continuity a good fuse has continuity a bad fuse has no continuity Conductor A A material that allows free movement of electrons allows electrical flow Conductors have three or fewer valence electrons 2 These electrons leave their shell easily B Examples of good conductors 1 Gold 2 Silver 3 Copper 4 Aluminum 5 Steel 6 A Insulator Material that does NOT allow for free movement of valence electrons 1 Insulators have 5 or more valence electrons 2 These electrons are reluctant to leave their shell B Examples of insulators 1 Rubber 2 Plastic 3 Air 7 Semi conductor A Manmade substance who s electrical conductivity is between that of an insulator and a conductor depending on the conditions 1 Semi conductors have 4 valence electrons 2 Can instantly be signaled to convert to 5 or 3 valence electrons B Semi conductor mate
5. 1 2 Paper tap lightly blow it off with air not more than 30 PSD A If filter is oily it can be cleaned with soap and water Foam wash with a strong detergent than rinse when dry apply 1 tablespoon of oil to element squeeze in and use paper towels to soak up excess Gauze K amp N wash in a strong detergent than rinse shake off and air dry not air pressure spray with light coat of K amp N oil on outside until gauze is pink Ham can order of assembly A Manifold to head B Carburator to manifold C Air cleaner backing plate to carburator D Align and tighten support bracket last prevents pulling manifold from heads which causes air leaks THROTTLE CABLE ADJUSTMENT aa Lubricate cable with a light viscosity lubricant Insure proper routing of cables not pinched or crimped Pull open cable with front end straight open throttle wide open A Adjust pull open cable until crank on carb just touches carb stop snug locknut Return cable turn front end all the way to the right lock A Adjust pull closed cable to eliminate freeplay between outer cable and cable spring B Check throttle snap back in left right and straight position throttle must turn freely in any front end position C Carburator overflow hose must be routed away from exhaust D Inspect fuel system for leaks or damage hoses fuel valve lubricate VEHICLE INSPECTION tech 2 Tech 2 1 Around the vehicle inspection similar to
6. 2 oil collects in gearcase cover and drains into mini sump 3 things control oil return 1 spinning of flywheel and case scraper 2 downward action of the piston creating pressure in the case 3 suction of oil pump return gears Harley Davidson Tech 1 26 Intro Dates a 883 started in early 1986 to present b 1100 started in late 1986 to late 1987 c 1200 started in early 1988 to present Case breather sportsters from 1986 1990 Iron sportsters from 1957 1985 27 Compression Ratio a 9 1 on ALL models 28 Rocker covers a Big Twins B T and Sportsters XL can be interchanged as a set i Top end breather covers must be used on top end breather motors ii Print o seal gasket and inner cork or rubber chimney are the same for B T and XL iii All rubber gaskets from late 1989 till current iv XL rocker arms and shafts are the same as the B T 29 Rocker arm play is 0 003 to 0 013 between rocker arm and rocker box endplay 30 Bolts are hardened and CANNOT be replaced or mixed with unhardened bolts 31 Rocker shaft to Rocker box clearance for all XL s is 0 0007 to 0 0022 ID to OD clearance 32 9 16ths 18 tap is used to push out rocker arm bushings from the opposite side then press in new bushings 33 Pushrod tubes a 1986 1990 i multipiece tube ii both top and bottom seal against an o ring 34 Cylinder Head a Early 883 egg shaped chamber and sand cast b Late 883 round hemispheri
7. 3 What is a venturi e A constriction within a tube 4 How does the fuel get into the venturi of the carburetor e The lower pressure in the venture draws fuel from an atmospherically vented carb bowl 5 What is the advantage of a large venturi e Allows for better performance at higher RPMs 6 What is the advantage of a small venturi e Allows for better throttle response in low and mid range RPMs 7 What are the 2 main types of venture designs found on motorcycle carbs e Fixed venturi e Variable venturi 8 What are the 2 types of variable venturis e Mechanical slide controlled directly by the rider throttle e Constant velocity AKA Constant vacuum controlled by pressure differences
8. CLUTCH XL 4 SPEED General A snap ring assembly B can be removed piece by piece or as a complete assembly C use a clutch spring compressor for disassembly Clutch spring A diaphragm same strength as old double coil B special washers round edge to spring Clutch A fiber friction drive 1 010 max warpage 2 130 minimum thickness 3 when installing new soak in oil for at least 5 minutes B steel driven 1 010 max warpage 2 060 minimum thickness 3 stamped steel smooth rounded edge faces out Spring plate A check for loose rivets B measure for variance max of 020 Rotor A part of clutch shell assembly magnets are fragile 6 Clutch hub bearing A beefed up L86 reduces looseness ACCESS DOOR XL 4 SPEED Stator mount Torx screws ioe A 30 40 in lbs B loctite encapsulated on threads 3 Before removal measure transmission shaft end play 4 To remove access cover shock dowel pins or heat around dowel pins TRANSMISSION XL 4 SPEED General 4 Speed Direct drive 1 to 1 ratio in 4th gear Sliding gear Sprocket 21T Right hand threads 65 90 ft lbs mow gt Check end play of main shaft and counter shaft before removing access door Gear spacing can be accomplished by changing shift forks and or spacer washers A Forks come in standard 005 010 or 020 sizes This changes spacing of individual sliding gears B Different thic
9. THEORY NOTES SUBJECT Mechanical slide carburetors e SEE FIGURE 8 10 and 8 14 KEY POINTS 1 Circuits A The idle circuit is also called the slow speed or pilot circuit e SEE FIGURE 8 15 e Main characteristics e Main effect to fuel flow is from idle to about throttle opening e Flows fuel 100 of the time overlaps all other circuits e Has the smallest fuel jets and therefore is usually the first circuit to plug due to contamination 1 Idle air bleed passage a Located at the mouth atmospheric side of the carburetor b Purpose Aids in atomization by mixing air with fuel c Some air bleed passages may use a removable air jet d Air jet number indicates flow rate the larger number indicates the larger jet 2 Mixture screws e SEE FIGURE 8 27 a Motorcycles have an air mixture screw or fuel mixture screw but usually not both b Most current motorcycles have factory installed anti tamper plugs over mixture screws to prevent the untrained consumer changing the setting c Adjustments are done from initial settings when the engine is at normal operating temperatures NOVEMBER 22 1999 PAGE 2 1 Air mixture screw Usual starting point is 1 turns out 2 The fuel mixture screw has a pointed end and is very easy to damage if seated too hard la See service manual for initial setting d Mixture screw differences e AIR MIXTURE SCREW e Located on the air filter housing side on the carburetor e Varies the flow rate o
10. 2 Fiber resins 3 Carbon fiber f Piston skirts in cylinder reed valve engines will be cut away or have windows cut into it g Some cylinder reed valve engines use NOVEMBER 5 8 1999 PAGE 7 1 Boost ports la Direct passage way for fresh charge to flow from intake manifold to the secondary area lb Purpose To increase the density of the fresh charge in the secondary area 2 Boost bottle la Small chamber attached by a hose to the intake manifold after the carburetor lb Purpose To increase the density of the fresh charge 3 Auxiliary port la A direct passageway for fresh charge to flow from the intake manifold to the primary area lb Purpose To increase the density of the fresh charge in the primary area 3 Rotary valve engines e SEE FIGURE 5 16 a Intake port is located on the crankcase b Opening and closing of the port is controlled by a rotary disk attached to the crankshaft c Motorcycle rotary valve engines are normally wider because 1 Each cylinder will have its own carburetor attached to the side of the crankcase 2 Each cylinder will have its own disk d Watercraft uses one rotary valve for two cylinders due to manifold design e Engine will usually have a wider power band because 1 1 3 more area to add more transfer ports 2 Shorter and more direct intake path into the primary area f Disadvantages 1 Extensive machining required when manufacturing 4 Crankcase reed NOVEMBER 5 8 1999 PAGE 8 a
11. TEDNA wW p disconnect battery slacken clutch cable all the way remove clutch screw lock and spring turn counterclockwise until firm turn clockwise 1 4 to 1 2 turn replace screw lock and spring G adjust cable for1 16 cable freeplay Primary chain adjustment A disconnect negative battery terminal B take out slack in primary chain C rotate wheel to find tight spot D adjust to 3 8 to 1 2 slack Oil level and type A H D sport transmission fluid 1 designed for higher loads 2 retrofits all wet clutches B 4 speed 1 24 oz measured 2 fluid should just dribble out of level plug with motorcycle upright C 5 speed 1 32 oz measured or just up to diaphragm spring on clutch Cover removal A disconnect battery B release chain adjuster C remove clutch screw nuts D remove fasteners Clutch release A powdered metal B M 923 late model parts 1 angle of ramp and coupler changed helps prevent breakage caused by misalignment C retro fits as set to 84 1 2 Motor sprocket and chain same since 57 A torque to 150 160 ft lbs use Loctite 242 B use lock link tool to hold sprocket Motor sprocket nut A it was first a grade 2 hex nut B than a grade 5 hex nut C now a grade 8 nut with a flange D torque to 150 165ft lbs Use Loctite 262 Source of oil leaks at primary gasket surface shift shaft seal to cover foot peg shaft starter motor clutch cable screw adjuster mm oO
12. f g Operation is the same as 77 pump Feed gear height 0 001 0 011 above pump cover Feed gears were enlarged to supply lifters i Return gears are still larger than feed Gear clearance inner and outer gear i Wear limit 0 004 ii Use shaft to center gears in body Seal lip numbers side toward feed side Oil pressure i Measure at the top plug in the case or the sending unit on the filter housing 1 Factory specs 1 7psi at idle and 5 30psi at 2500 rpm 2 If taken at the sending unit readings will be double Oil flow i Flows from oil tank to the pump cover ii Feed gear pressurizes oil through small hose to housing 1 Special hoses 2 different fitting sizes no sealant needed iii Oil filter adapter housing 1 Pressurized oil to adapter housing 2 Enters adapter through drilled holes and fills cavity 3 Builds 2 4psi activates sending unit and oil light turns off 4 Cold oil pressure high oil pressure 5 Pressure regulator bleeds off excess oil to gearcase opens at 16 18psi 6 Regulator left out or stuck open lifter collapse and oil pressure drop 7 Oil through filter to center of filter 8 Oil through check valve a Opens at 4 6psi b Check valve creates backpressure activates sending unit faster c Arrow on valve indicates direction of flow d Should point towards adapter with o ring to the outside counter bore e If installed backwards it will damage the o ring and create unfiltered p
13. la Mikuni slides range from sizes 1 to 3 5 with 0 5 increments lb 1 is the richest and 3 5 is the leanest B Mid range circuit 1 Operation 4 to throttle opening 2 Mid range ports a Jet needle e SEE FIGURE 8 17 1 Long tapered needle moves with the slide 2 The taper varies the amount of fuel flow through the needle jet 3 At throttle opening there is more restriction than a 34 throttle opening 4 Attached to the bottom of the slide and positioned inside the needle jet 5 Non EPA carburetors will have five static height clip positions NOVEMBER 22 1999 PAGE 4 6 Number one top groove is the leanest 7 Number five bottom groove is the richest e To make it richer add washers 3 mm X 1 20000 b Needle jet a e SEE FIGURE 8 17 Stationary in the carburetor body Numbered for its flow rate The larger the number the richer the entire range Located in series with the main jet Contains the air bleed tube for mid range and main jet circuits Three types of needle jets la Bleed e Identified by several air bleed holes e Sits flush with the venturi floor e Allows for good atomization of fuel lb Primary e Has a hood that protrudes into the throat of the carburetor e The hood acts similar to an airfoil in other words it increases the negative pressures above it e This type allows the best throttle response e Has only one air bleed hole e Used mostly in two stroke engines lc Primary bleed e Combination of
14. 2 Engine is sealed and pressurized to 6 to 9 PSI 3 Maximum leakage is one PSI per minute 4 Ifthe engine shows no leakage then a vacuum test should be performed 5 A vacuum is placed in the engine of nine inches of mercury 9 hg 6 Maximum leakage is one inch of mercury per minute b Areas of possible leakage are 1 Exhaust seal part of test equipment 2 Intake manifold gasket 3 Cylinder head or base gasket 4 Timing side seal 5 Primary side seal 6 Center crankcase gasket 7 Test equipment 8 Two stroke engine lubrication A Two stroke engines use a total loss lubrication system B Oil is not recirculated through the engine C Itis burnt during combustion and exits through the exhaust system D Two methods e Pre mix e Oil injection 1 Premix a Simplest in design oil is mixed with the fuel at a certain ratio in the fuel tank NOVEMBER 8 9 1999 PAGE 7 b Example 1 20 1 indicates that there are 20 parts volume of fuel to one part of oil c Formula to calculate the quantity of oil needed in ounces is 1 128 divided by ratio times the number of gallons ounces 2 Example la 32 1 ratio and 5 gallons of fuel 128 divided by 32 times 5 equals 20 ounces of oil d Any change in pre mix ratio will affect the air fuel mixture ratio 1 Decrease in pre mix ratio will result in a lean air fuel mixture ratio 2 Example la A change from 32 1 to 20 1 will result in a lean air fuel mixture ratio
15. 3 when boring or honing use torque plates and gaskets 4 cylinder inspection a base surface 003 max warpage b wear limits max clearance 006 cylinder to piston 0015 003 good max taper 002 max out of round 001 c finish 240 plateau when sizing cylinder use torque plates and gaskets G Pistons 1 60 83 Bohnalite USA made H D machined cast in steel strut controls expansion tin coated for break in symetric no wrist pin offset wrist pin clips 72 77 spirolox and 77 and up use Tru arc pistons will be marked with 78 part number or 77 cast into piston can use a spirolox in a Tru arc piston but not the reverse 2 compression ratio a 1200cc high compression 8 1 FLH round dimple in crown b 1200cc low compression 7 4 1 FL no dimple c 1340cc high compression 8 1 FLH rough crown d 1340cc low compression 7 4 1 FL smooth crown 3 wrist pin see service bulletin hand out page 3 15 a 74 pistons have lowered wrist pin locations for use with 030 shorter connecting rods b 53 and 55 pistons have higher wrist pin location for use with longer rods 36 and 41A 4 piston clearance 001 002 with a max of 006 5 Mahle pistons L83 84 a German made b very hard 12 silicone content c approximately 100 grams lighter than Bohnalite d wire type pin clip use special Kent Moore tool to install gap at 12 00 e wri
16. A Defined as a lever that transfers power from the piston to the crankshaft B Usually made of forged steel or aluminum I beam construction C Types 1 One piece a Strongest in design b Uses a roller bearing at the big end c Must be used with a multi piece crankshaft d Normally has holes or slots on the small end bearing and journal 2 Multi piece e SEE FIGURE 4 48 a Weaker in design b Parts consist of 1 Connecting rod 2 Connecting rod cap 3 Connecting rod bolts 4 Sometimes connecting rod nuts c Uses a plain bearing at the big end d At the big end bearing it normally requires high pressure and volume of oil for lubrication e Usually used with a one piece crankshaft f Always replace rod bolts and nuts after disassembly NOVEMBER 3 1999 PAGE 2 2 Crankshafts A Purposes Change a reciprocating motion into a rotary motion B Journal A bearing support area of a shaft C Parts of the crankshaft 1 Main Journals Supports the crankshafts mass Center of the rotating access 2 Connecting rod journal Supports the connecting rods Offset to the main journals axis D Crankshaft throw 1 Distance from the centerline of the main journal to the centerline of the connecting rod journal 2 Formulas a Throw X 2 Piston stroke b Stroke divided by 2 Throw E Counter Weights 1 Purposes a Adds momentum to the crankshaft b Used to counterbalance reciprocating masses 2 Some engines use remote co
17. Bore 3 504 in 2 Stroke 3 583 in 3 CV 3 504 X 3 504 X 3 583 X 0 7854 34 551 cubic inches ci 2 Engine Displacement ED The volume of all cylinders A Formula Bore X bore X stroke X 0 7854 X number of cylinders engine displacement B Metric C Metric unit for measuring volume is cubic centimeters cm3 D Bore and stroke must be converted to centimeters 10 mm 1 cm E Metric example 1 Bore 89 mm converted 8 9 cm 2 Stroke 91mm converted 9 1 cm NOVEMBER 4 1999 PAGE 2 3 Cylinders 2 twin 4 ED 8 9 X 8 9 X 9 1 X 0 7854 X 2 1132 250 cubic centimeters cc F English standard example 1 Bore 3 504 inches 2 Stroke 3 583 inches 3 Cylinders 2 4 ED 3 504 X 3 504 X 3 583 X 0 7854 X 2 69 103 cubic inches ci 3 Compression Ratio CR A Numerical ratio of volume above piston at BDC compared to volume above piston at TDC B Service manuals usually express compression ratios as first number rounded to tenths 1 C Compression ratios generally range 5 5 1 to 16 0 1 D Formula CV CCV divided by CCV CR e CV cylinder volume swept volume volume passed by piston movement TDC to BDC e CCV Combustion chamber volume volume above piston at TDC 1 Metric example a CV 275 440 cc cubic centimeters b CCV 34 4 cc c CR 275 440 34 4 divided by 34 4 9 0 1 2 Standard example a CV 34 551 ci b CCV 3 967 ci c CR 34 551 3 967 divided by 3 967
18. C Momentum The driving force of a moving object Weight mass X Velocity Momentum D Law of Inertia Opposition matter has to any change in motion Anything at rest or in motion will remain at rest in motion until acted upon by an outside force E Action and Reaction For every action there is an equal and opposite reaction 7 Energy The ability to do work A Thermodynamics Law Predicting effects of heat and transfer of energy 1 Energy cannot be created or destroyed 2 It exists we do not see it we only realize its results 3 Energy can be changed from one form to another form 4 Energy can also change matter 5 Energy is released when matter or energy is changed 6 Noconversion of energy or matter is 100 efficient B Active energy Common occurring forms of energy such as 1 Light converted to color 2 Potential energy converted to motion OCTOBER 27 1999 PAGE 3 Electrical converted to reactive substances C Potential Energy Stored energy that can be released slowly or all at once 1 Crude oil derivatives 2 Fully charged battery 8 Work The useful movement of an object A Formula Force X Distance of movement WORK Force X Distance B Work may be expressed as any Force unit X any Distance unit C Force unit examples Pounds Ib or kilograms kg D Distance unit examples Inch in or or foot ft or or meter m 1 Example 1 Force 25 pounds moves through a distance of 25
19. Dry lubricants 1 Purpose To lubricate with out attracting contaminants 2 Lubricant that uses a solvent as a carrier 3 When applied the solvent vaporizes leaving the lubricant END OF FOUR STROKE ENGINE OILS SND LUBRICANT NOTES THEORY NOTES SUBJECT Four Stroke Operation KEY POINTS 1 Basic Terminology A Stroke s Piston travels from dead center to dead center B Event A process that occurs at or nearly at the same time as a stroke but not in lock step C Top Dead Center TDC The point at which the piston is at the farthest distance from the crankshaft 1 ATDC After Top Dead Center 2 BTDC Before Top Dead Center D Bottom Dead Center BDC The point at which the piston is closest to the crankshaft 1 ABDC After Bottom Dead Center 2 BBDC Before Bottom Dead Center FOUR QUADRANTS TWO REVOLUTIONS 720 degrees TWO TDC S 1 TDC Compression TDCC 2 TDC Overlap TDCO TWO BDC S ALL EVENTS REFERENCE TO TDC OR BDC 2 Five events of a four stroke engine OCTOBER 28 29 1999 PAGE 2 A Completion of a four stroke engine s cylinder requires 1 Four strokes of a piston intake compression power exhaust e SEE FIGURES 4 2 4 3 4 4 and 4 5 2 One revolution of the camshaft camshaft turns at half of the speed of the crankshaft 3 Two revolutions of the crankshaft 720 degrees of rotation B Five events in order are e Intake event e Compression event e Timed ignition event e
20. Method of riding The heavier the load of the engine the better chance of detonation Engine s compression ratio The higher the compression ratios the better the chance of detonation 3 Types of fuels Made up of hydrogen and carbon atoms known as hydrocarbons Gasoline Alcohol A Gasoline NOVEMBER 18 1999 PAGE 2 e Types of gasoline e Leaded gasoline e Unleaded gasoline e Oxygenated fuels 1 Leaded gasoline a Prohibited by the government EPA in most states to reduce pollution b Uses tetraethyl lead as an additive to 1 Increases the octane rating 2 Lubricate and act as a cushion for the valve face and seat area 3 Used in quantities of less than a tenth of a gram per gallon of gasoline 2 Unleaded gasoline a Has no lead additives b Uses iso octane and heptane to improve the quality 1 Iso octane A hydrocarbon derivative la Octane rating of 100 increases the octane rating of the fuel 1b Determines the compressibility of gasoline 2 Heptane A hydrocarbon derivative la Has an octane rating of zero 1b Determines the burnability of gasoline 3 Oxygenated fuels a Fuels that contain more oxygen molecules than regular leaded or unleaded gas b Purpose Decrease carbon monoxide emissions by approximately 15 c Common additives used to raise the oxygen content 1 Ethanol la Produced by fermentation NOVEMBER 18 1999 PAGE 3 1b Not recommended in quantities above 10 Methanol la
21. Spiral lock 4 Buttons a Always install clip end gap in line with the connecting rod C Never reuse wrist pin retainers END OF FOUR STROKE CYLINDERS PISTONS AND PISTON RINGS NOTES NOVEMBER 16 17 1999 THEORY NOTES SUBJECT Four stroke engine oils and lubrication systems e SEE FIGURES 7 1 and 7 9 KEY POINTS 1 Purposes of oils A Clean suspend contaminants B Cool transfers heat C Seals forms a seal between clearances D Lubricate reduces friction 2 Origins of oil base stock e Mineral base e Synthetic base e Animal base e Vegetable base A Mineral base 1 Product of crude oil 2 Performs poorly without additives a few of the additives are a Sulfur and Phosphorus Used to improve the oil s extreme pressure properties b Zinc Used to increase shear strength c Viscosity improvers d Anti foaming agents e Detergents f Dispersants 3 Base oil does not break down the additives do NOVEMBER 16 17 1999 PAGE 2 a Additives start to break down quickly at temperatures of 275 degrees Fahrenheit B Synthetic oils 1 Made by recombining the molecular structure of various hydrogen and carbon based products 2 Advantages a Better lubricant b Less evaporative c Can handle higher temperatures d Less viscosity change with temperatures e Not affected by fuel contamination 3 Disadvantages a Can not be used in 1 New engines 2 Engines with excessive clearances b Can seep at ga
22. Where does secondary compression take place e In the combustion area above the piston crown List 5 types of 2 stroke induction systems e Piston port Cylinder reed valve Rotary valve Crankcase reed Piston port and crankcase reed 20 21 22 23 24 25 What induction system is the simplest but has a very narrow powerband e Piston port What is the purpose of the reed valve in the intake track and how does it affect the powerband e Allows for higher RPM and prevents spitback through the carb while broadening the powerband What are 3 materials commonly used in the construction of the reed petals e Stainless steel e Fiberglass fiber resin e Carbon fiber What is the function of the Boost Port e Allows for better loop scavenging What is the function of the auxiliary port e To increase the density of the fresh charge in the primary area What controls the opening and closing of the intake port on a rotary valve 2 stroke e A rotary valve 3 Jet Carburetors Cold Star Systems Auxiliary Circuits and Fuel Injection carb 10 11 12 13 What is the main advantage of a 3 jet carb over a 2 jet carb e Better atomization in the midrange For most 3 jet carbs the slide and throttle plate control the airflow What are considered to be the 3 jets in a 3 jet CV carb e Slow jet e Primary main jet e Secondary main jet At what throttle opening does the idle circuit have its main effec
23. always replace B steel all gears 36 p n counter and main are different C fork blocks 1 36 E 76 rounded 1 notch 2 L 76 E 79 square 1 notch 3 L 79 85 square 2 notches nuts face towards each other torque to 12 ft lbs nut locks bend only once shims adjust forks gear spacing shims go between fork and block only shift finger rollers top hats 1 long drum roller 2 short plate shifter and the XL 3 always replace Q HMO 23 Countershaft hand out page 3 14 24 25 A 36 77 threaded 1 grove 77 79 threaded 2 grooves 80 83 notched B max bend 003 runout max wear 001 C Ist gera free wheeler largest OD half speed bushing max clearance 004 total 1 thrust washer next on shaft D 1st and 2nd gear shifter clutch new mounts in either direction max backlash 010 E 2nd gear free wheeler second largest OD half speed bushing max clearance 004 total F countershaft cluster 3rd and 4th gear most expensive speedo drive in between 3rd and 4th gear G case race heat case to press in 1 threaded 1 groove shaft shouldered race on kicker side no shoulder on other race use loose roller bearings 2 threaded 2 groove shaft is 005 smaller in OD need different bushings used with caged bearings 3 notched shaft same as 2 groove Mainshaft A different lenght shafts pushrods also 1 36 64 short kickstart 2 6
24. connected to air cleaner to reroute vapors through the engine 5 evacuator system used on E81 E82 models hose connected pushrod tube area to cylinders system did not work causing oil consumption carbon deposits and pushrod tube leaks 6 typical breather and return system problems cause oil carryover a return restriction b over filled oil tank c leaking check valve d damaged breather valve or case e seperator hole plugged f breather trap gasket leaking E Return system 1 oil drains to bottom of gearcase 2 thick gears return pick up oil 3 oil returns to tank through fitting next to F fitting at top of pump 4 oil may also flow through filter and cooler before returning to tank F Updates 1 L82 engine oil changes reduce top end fitting to 090 do this to all shovels 2 drill the 2 holes through in the tappet guide 3 oil pump return hand out page 3 9 4 lip side of seal towards feed gears 10 Dry clutch A 30 84 1 2 dry multiplate with chain drive primary oil feed oil retrieved by engine vacuum 1 primary is oil fed oil is retrieved by engine vacuum 25 water vacuum at 1500 RPM vent pinched B C friction plates 020 max warpage can be scuffed up steel plates 010 max warpage scars 1 32 or more replace grove wear 020 max D engine installation friction plate first and last crankcase seal installs lip in to keep oil out of dry primary 1
25. power event at the end of the power stroke 2 Closes ATDC during the intake event at beginning of intake stroke C Valve overlap 1 The point at which the intake and exhaust valves are open at the same time The exhaust valve is closing and the intake valve is just beginning to open 2 Valve overlap occurs at the end of the exhaust stroke and at the beginning of the intake stroke 3 Purposes a Scavenge residual exhaust gases b Helps cool combustion chamber OCTOBER 28 29 1999 PAGE 5 c Not all engines have overlap example Honda GL1500 4 Advantages a Better volumetric efficiency at high RPM resulting in horsepower increase at higher RPM b Helps cool combustion chamber 5 Disadvantages a Loss of torque and horsepower in mid range and lower RPM range b Higher hydrocarbon emissions c Lower fuel mileage END OF FOUR STROKE OPERATION NOVEMBER 18 1999 THEORY NOTES SUBJECT Friction reducing devices KEY POINTS 1 Purposes A Reduces friction B Take up shaft end play C Proper spacing D Support axial thrust and radial loads 2 Definitions A Axial thrust loads Side to side loads tries to move the shaft end to end B Radial loads Rotating load tries to twist the shaft C Journal Area of the shaft that turns on and is supported by a bearing or bushing 3 Types e Ball bearing e Roller bearing e Needle bearing e Tapered roller bearing e Precision insert bearing e Thrust bea
26. stock bore a 883 3 00 b 1100 3 35 c 1200 3 50 d 883 can be bored out to 1200 14 pistons a Karl Schmidt German b 1986 to early 1989 no offset on piston for 883 and 1100 install either direction c late 1989 to present 883 and 1200 pistons have offset with the arrow on piston crown facing forward d As of October 1994 883 pistons are coated with Teflon for break in 15 Piston pin a 883 is shorter than 1100 or 1200 diameter is the same b 1200 same 1340 but are NOT interchangeable c 1200 have either 12 or a V grove stamped on the edge 16 Tappets a XL same as B T b No restrictor on Early 1986 c Ristrictor added Late 1986 1990 i Reduces oil to the top end ii Helps keep lifter filled at highway speeds hydraulic lifters as opposed to solid d Tappet working ranges 17 Tappet block 4 speed a Toremove from case turn tappet block and lift from case b Tappet to block fit i 0 0008 to 0 0023 ii 0 003 service wear iii there are no stock oversizes available c new o rings are made from silicone rubber and will swell when exposed to oil d oil leaks i tappet block to case oil will be grungy ii small o ring to case oil will be dirt free possible that the counterbore is to deep in the case should be 0 050 0 060 18 19 20 wm ma e iii shim up with a small washer iv use Hylomar to seal Torque to 15 18 ft lbs Ge
27. 000 PSI e Hot expanding nitrogen gases cause a rapid pressure rise that drives the piston down f Detonation may occur in this phase 3 Post combustion activity Starts when pressure peaks and charge have been consumed a Piston is descending toward BDC 1 Above the piston la Pressure is decreasing 2a Temperature is decreasing b Usable horsepower is no longer being made OCTOBER 27 28 1999 PAGE 3 c Exhaust event starts during this activity before BDC 1 Rids cylinder of spent exhaust gasses pressure 2 Prepares for the next event intake d All engines begin to release exhaust well before the piston reaches BDC B Abnormal combustion Two types 1 Pre ignition auto ignition initiated before normal timed ignition a Can be caused by hot spots inside the combustion chamber b Examples glowing spark plugs carbon and gasket materials c Symptoms of pre ignition after it has occurred over a long period of time 1 Common Damage to piston usually crown of pistons molten appearance 2 Severe case Hole in top of piston 2 Detonation Spontaneous combustion violent explosion that occurs after timed ignition a Explodes the end gases last part of the air fuel mixture during the compression ratio used b Usually caused by extreme temperatures and unsuitable fuel for the compression ratio used c Most common symptom Damage to piston usually ring land area of a jagged crushed appearance d Causes high frequency
28. 2 Scraper ring a Middle ring b Aids in sealing combustion gasses c Aids in scraping excessive oil off of cylinder walls d Usually made of cast iron 3 Oil control rings a Closest to the piston skirt b Removes most of the oil on the cylinder walls left behind by the piston skirt c Styles NOVEMBER 2 3 1999 PAGE 6 1 One piece la Usually made from iron very thick and heavy very brittle 1b Does not conform to out of round cylinders very well 2 Multi piece la Uses a wafer shape expander and two thin flexible rails 1b Does conform to out of round cylinders C Piston ring end gaps 1 Purposes a Allows for heat expansion b Allows for proper compression c Allows for oil control 2 Endcap a Too little ring end gap can result in seizure b Too much ring end gap can result in loss of compression and excessive blow by c Measured by using a feeler guide blade after fitting the ring squarely to the cylinder D Installation 1 Install with markings facing towards the piston crown 2 Stagger end gaps approximately 120 degrees apart from each other to prevent blow by 4 Wrist pins A Purpose Connect the piston to the connecting rod B Usually made of hardened tool steel C Usually held in place with retainers some are press fit 5 Wrist pin retainers A Purpose To prevent the wrist pin from contacting the cylinder wall B Types NOVEMBER 2 3 1999 PAGE 7 1 Round wire clip 2 Flat wire clip 3
29. 3 An increase in pre mix ratio will result in a rich air fuel mixture ratio 4 Example la A change from 32 1 to 50 1 will result in a rich air fuel mixture ratio 2 Oil injection a Oil is stored in a remote tank b Engine driven pump injects proper oil amount into intake manifold and sometimes the main bearings c Pump output is controlled by engine RPM and throttle position d Best method for everyday street use 9 Most common causes of two stroke engine seizure A B Lean air fuel mixture ratios Causes excessive heat Lack of or too much lubrication Excessive load on the engine Causes overheating NOVEMBER 8 9 1999 PAGE 8 Improper clearances Do not allow for heat expansion Improper timing procedures Can cause binding on moving parts which causes excessive heat Cold seizure due to improper warm up END OF TWO STROKE ENGINE PARTS NOTES NOVEMBER 5 8 1999 THEORY NOTES SUBJECT Two stroke engine theory of operation KEY POINTS 1 Three major moving parts A Piston assembly B Connecting rod C Crankshaft 2 Basic terminology A Port holes in cylinder used to control air fuel oil flow no poppet valves used B Primary area volume below piston crown including the crankcase volume C Secondary area volume above the piston crown including the combustion chamber 3 Three ports Design and purpose A Intake port 1 Purpose controls flow of fresh charge into the primary area crankcas
30. 3 The internal combustion methods A Methods of initiating combustion 1 Ignition Contact of fuel with an already burning substance 2 Compression Reducing the space confining oxygen and a combustible material will eventually produce enough heat to start combustion 3 Spontaneously Slow oxidation creates some heat that speeds the chemical reaction In time enough heat is produced to start the combustion process example tightly packed oil rags OCTOBER 27 28 1999 PAGE 2 B Motorcycle engines us a combination of 1 Compression to preheat the air fuel mixture 2 Timed ignition to control when combustion will occur 4 Internal combustion process textbook page 18 A Normal combustion Process of combustion is divided into three separate phases 1 Combustion Lag Short period of burning that begins after timed ignition happens a Starts with timed ignition BTDC b Spark plug spark does not create an immediate explosion c Spark plug ignites a small portion of mixture at firing tip and burning starts to spread 2 Active Combustion Chain reaction burning takes place at great speeds after initial Lag has been overcome a Allows the flame front to propagate spread out to all areas of the combustion chamber b Usually occurs from BTDC to a few degrees ATDC c Peak pressure should occur ATDC by several degrees d Causes rapid building of 1 Temperatures high as 4 000 degrees Fahrenheit 2 Pressures 800 to 1
31. 30 is removed through the cooling system D Stroke efficiency 1 Percentage ratio comparing how far the piston travels under useful pressure to the total distance it travels OCTOBER 27 28 1999 PAGE 6 2 Affected by engine RPM stroke length and exhaust valve timing E Mechanical Efficiency textbook 26 27 1 Percentage ratio comparing how much power is produced to how much is lost 2 Affected by losses due to weight and friction END OF INTERNAL COMBUSTION NOTES NOVEMBER 4 1999 THEORY NOTES SUBJECT Math KEY POINTS 1 0 0 00 000 0000 WHOLE TENTHS HUNDREDTHS THOUSANDTHS TEN THOUSANDTHS 2 Rounding off final answers A When computing a formula involving multiple computations round off final answers only B Method to round off to thousandths 1 Ifthe ten thousandths column is 5 or more add 1 to the thousandths column and drop all digits from the ten thousandths column on 2 Ifthe ten thousandths column is less than 5 drop all digits from the ten thousandths column on 3 Examples a 0 987643 0 988 b 14 8676 14 868 c 14 9998754 15 000 C Method to round off to the tenths 1 If the hundredth column is 5 or more add 1 to the tenth column and drop all digits from the hundredth column on 2 If the hundredths column is less than 5 drop all digits from the hundredths column on 3 Examples a 0 987643 1 0 b 14 8676 14 9 c 14 9998754 15 000 END OF MATH NOTES NOVEMBER 22 1999
32. 33 34 35 36 37 38 39 40 41 What are the 3 ways to initiate combustion e Ignition e Compression e Spontaneity The internal combustion engine uses a combination of to start combustion e Ignition e Compression What are the 3 phases of normal combustion e Combustion Lag e Active Combustion e Post Combustion Give the definition of Combustion Lag e A short period of burning that happens after timed ignition but before peak pressures What forces the piston downward during combustion e Expanding heated Nitrogen gases Name the 2 forms of abnormal combustion Give a brief description of each Include the cause and what kind of damage can result e Pre ignition Auto ignition initiated before timed ignition occurs Caused by a hot spot in the combustion chamber and can cause a melting effect on the crown of the piston e Detonation Spontaneous combustion that occurs after timed ignition Caused by a hot spot in the combustion chamber and can cause damage to the edge of the piston around the ring land What engine design features determine whether normal or abnormal combustion occurs e Compression ratio e Engine load e Fuel quality turbulence e State of tune What are the 5 gases that can be found in the exhaust after combustion Carbon Monoxide CO Hydrocarbons HC Carbon Dioxide CO2 Oxides of Nitrogen Nox Water H20 What by products of combustion a
33. 90 ft lbs Check end play of main shaft and counter shaft before removing access door Gear spacing can be accomplished by changing shift forks and or spacer washers A Forks come in standard 005 010 or 020 sizes This changes spacing of individual sliding gears B Different thickness washers used to adjust spacing of gears on countershaft C Use go no go method of spacing in hand out Cam follower detent problems M 949 A L84 E87 Steel zinc B M87 L87 aluminum C L87 90 aluminum w counter bore Mainshaft A Ist gear largest dia gear 1 M 934 recall 061 a 87 28T gear some break switched back to 52A gear 27T 2 Radius on all Ist gears to case for lubrication a press off on with the bearing races B mainshaft 2nd and 3rd gears 1 same ratio since 57 2 3rd gear end play reduced by thicker washer running change 1986 a will retro fit to 1957 3 M 906 late gears smaller diameter a must be used on all 1100 s b early or late model ok on 883 c prevents root contact caused by 1100 shaft flexing d OK to mix early or late style on all xl models except 1100 or 1200 C mainshaft 4th gear clutch gear 1 needle bearing 2 running 1986 thrust washer it has a loose fit a oil slots to the outside don t use 3 1987 ratio change a E 17T b L 18T ID by groove in teeth c taller 1st through 3rd D Mainshaft 1 003 max bend 2 check with freewheeling gears and V blocks 6 Count
34. Basic operating principles 1 Both CDI amp TPI have a source of EMF to ignite the coil 2 Both CDI amp TPI have a triggering device a small coil of wire pulsar 3 The triggering devise sends a signal to the Ignition Control Module 4 The ICM send voltage to the ignition coil 5 Through mutual induction voltage is produced at the spark plug 6 The fuel vapors inside the engine ignite Magnetism 1 Principals of Magnetism A Magnetism is an invisible force B Poles north and south 1 ends of the magnet 2 A bar magnet suspended on a string will align itself approximately with the north and south poles of the earth C Flux lines 1 invisible lines of force surrounding the magnet 2 going from the north to the south pole 3 concentrated at the poles D If 2 magnets are placed next to each other 1 like poles will repel each other 2 unlike poles will attract each other 2 Types of magnets A Natural rock magnetite very weak not used on motorcycles B Permanent magnet 1 man made of metal alloys 2 strong long lasting magnet commonly found on motorcycles C Electro magnet 1 current flowing through a conductor creates a magnetic field around the conductor 2 the increase the magnetic effect a the current flow can be increased b the conductor can be coiled 1 especially if coiled around iron a Iron has high permeability ease in which flux lines pass through a substance b Iron is 2000x as permeable as air c two types o
35. Opens at 4 6psi b Check valve creates backpressure activates sending unit faster c Arrow on valve indicates direction of flow d Should point towards adapter with o ring to the outside counter bore e If installed backwards it will damage the o ring and create unfiltered path for oil flow Late 1987 has a new valve rubber ball spring and new fitting i Ball to change in material and size m 950 1 Some sticking shut 2 Also redesign of adapter g 1992 production change ball was changed again has a tail PN 33116 86A oil back to pump through large hose through pump and into engine case and gearcase cover first to lower end 1 restrictor on pinion shaft reduces oil flow to rods 2 increases oil flow to top end vii path through gearcase cover and case sends oil to tappet blocks lifters pushrods and rocker arms viii all other areas are splash and drip Iron heads 80 oil to bottom end 20 to top end Evo engines 20 oil to bottom end 80 to top end ix x oil returns though cylinder drain holes and pushrod tubes 1 oil collects in mini sump 2 oil collects in gearcase cover and drains into mini sump 3 things control oil return 1 spinning of flywheel and case scraper 2 downward action of the piston creating pressure in the case 3 suction of oil pump return gears PRIMARY DRIVE AND COVER 1 Clutch cable AO OR sits below oil level Hylomar on threads copper
36. Power event e Exhaust event 1 Intake event a Intake valve usually begins to open BTDC during exhaust event at end of exhaust stroke b Piston passes TDC and travels toward BDC c Exhaust event ends when exhaust valve closes ATDC during the intake stroke d Volume in the cylinder is increasing temperatures and pressures are decreasing e Fresh charge is pushed into the cylinder f Ends when intake valve closes ABDC at beginning of compression stroke e SEE FIGURE 4 2 2 Compression event a Begins when intake valve closes ABDC during compression stroke b Piston is traveling from BDC toward TDC c Cylinder volume is decreasing pressures and temperatures are increasing OCTOBER 28 29 1999 PAGE 3 d Fresh charge is compressed and preheated e SEE FIGURE 4 3 3 Timed ignition event a Usually begins BTDC b Allows for combustion lag c Allows time for piston to reach slightly ATDC at point of peak pressures and temperatures d Most engines advance the timed ignition point as the engine RPM increases 1 Air fuel mixture burns at approximately the same speed 2 As the engine speed increases five events occur faster and there is less time for air fuel mixture to burn 3 Timed ignition point is advanced electronically or mechanically la Advancing the timing Making the timed ignition occur before earlier than some given point usually the manufacturers specified timing at idle lb Retarding the timing means mak
37. XL s have longer valve stems than B T e There are no service values available 13 Cylinders a Different castings between the 3 different motors i 883 1100 and 1200 stamped into bottom right corner of cylinder ii cylinders are all the same length and use the same sleeve iii sleeve is just bored out more for the larger displacement 1 stock bore a 883 3 00 b 1100 3 35 c 1200 3 50 d 883 can be bored out to 1200 14 pistons a Karl Schmidt German b 1986 to early 1989 no offset on piston for 883 and 1100 install either direction c late 1989 to present 883 and 1200 pistons have offset with the arrow on piston crown facing forward d As of October 1994 883 pistons are coated with Teflon for break in 15 Piston pin a 883 is shorter than 1100 or 1200 diameter is the same b 1200 same 1340 but are NOT interchangeable c 1200 have either 12 or a V grove stamped on the edge 16 Tappets a XL same as B T b No restrictor on Early 1986 c Ristrictor added Late 1986 1990 i Reduces oil to the top end ii Helps keep lifter filled at highway speeds hydraulic lifters as opposed to solid d Tappet working ranges 17 Tappet block 4 speed a Toremove from case turn tappet block and lift from case b Tappet to block fit i 0 0008 to 0 0023 ii 0 003 service wear iii there are no stock oversizes available c new o rings are made from silicone rubber and will swell when exposed
38. a circuit to function improperly e Open e Ground e Short Define the following circuit problems e SHORT Alternate source to ground BEFORE the load device e OPEN break in the path with no route to ground e GROUND alternate route to ground after the load device but before the means of control What is the purpose of a fuse or circuit breaker e Circuit protection What is a series circuit e Only one path for the current to flow from source back to source What is the formula for finding the total resistance in a series circuit e The sum of all individual resistances the total In a series circuit the amp flow is the same in all parts of the circuit while the voltage drops depending on how much resistance each load has What is a parallel circuit e More than one path from source back to source What is the formula for finding the total resistance in a parallel circuit e The reciprocal of the sum of the reciprocals of each resistance What would happen to the total resistance if another branch leg were added to a parallel circuit e It would drop 12 In a parallel circuit the voltage to each branch leg is the same while the amps drop through each branch or leg depending on the resistance HW Electrical Operation l What is the Ohms Law basic formula e volt pushes 1 amp through 1 ohm De What are the 3 Ohms Law formulas e Volts amps ohms e Volts ohms amps e Ohms amps volts 3 What does Watts Law s
39. also called a high speed circuit E Cold start systems 5 Circuit operation ranges specified to motorcycle see the service manual A Most manufacturers specify throttle position Example Idle circuit 0 to throttle B Some manufacturers specify engine RPM Example Idle circuit 0 to 1000 RPM s C Theory clinic uses throttle position for lesson purposes only 6 Auxiliary circuits A Accelerator pump NOVEMBER 19 1999 PAGE 2 e SEE FIGURE 8 24 B Air cut off valve e SEE FIGURE 8 21 C Power jet END OF CARBURETOR BASICS NOTES NOVEMBER 10 12 1999 THEORY NOTES SUBJECT Clutches KEY POINTS 1 Purpose A Engage and interrupt the power flow from the engine to the transmission B Permit gradual engagement 2 Types e Manual wet or dry multi or single plate clutch e SEE FIGURE 6 9 e Centrifugal semi automatic clutch e SEE FIGURE 6 18 e Variable ratio clutch e SEE FIGURE 6 10 e Sprag clutch e Torque converter e SEE FIGURE 6 19 A Manual clutches 1 A clutch that the rider controls engagement and disengagement of the power flow 2 Clutches can be either wet or dry a Wet clutches 1 Operates in an oil bath 2 Engine oil carries heat away from the clutch 3 Usually smoother engagement than a dry clutch 4 Wet clutches normally use a cork neoprene paper or kevlar friction material NOVEMBER 10 12 1999 PAGE 2 b Dry clutches 1 Operates dry 2 Uses air flow to cool the clutch 3 Has a mo
40. and provides a thrust and sealing surface for the rings What are 2 ways that pistons can be manufactured e Cast e Forged Why are pistons tapered e To allow for different expansion rates from piston crown to skirt Why are pistons cam ground e To allow for wristpin expansion When heated piston becomes round cylindrical List the parts of a 4 stroke piston e Crown Ring land ring groove Oil ring groove Wrist pin boss Skirt Where s the pistons largest diameter e Around the skirt 90degrees to the wrist pin boss What is the purpose of the wrist pin hole being offset to one side of the piston skirt e Helps reduce noise from the piston in the cylinder Piston is always tilted to the same direction instead of being able to flop back and forth Where do the letters or numbers face when installing piston rings e Usually they face up but consult the manufacturer service manual 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 List 3 rings used o most 4 stroke pistons and their main purpose e Compression ring Seals most combustion gases and aids in heat transfer e Scraper ring Aids in sealing combustion gases and aids in scraping oil from the cylinder walls e Oil Control Ring Removes most of the oil from the cylinder wall What is the purpose of the ring end gap e Allows for heat expansion e Allows for proper compression e Allows for
41. and guide into the combustion chamber D Neck 1 Area that slopes to the valve head 2 On two piece valves this is the area where they are joined 3 Usually contoured for good air flow E Face 1 Area that mates with the valve seat 2 Seals and aids in heat transfer 3 45 degree angle most 4 Often stellite coated 5 Wear area F Margin 1 Supports the face 2 Shields the face from high combustion chamber G Head 1 Aids in forming the combustion chamber 2 On two piece valves the head is usually made of different material than the stem because it must tolerate more stress and heat OCTOBER 29 1999 PAGE 4 3 Wear areas of the valve a tip b face c stem d keeper groove 4 Valve stem seals A Seals are installed on the valve guides B Neoprene or teflon type oil seals C Function Prevents excessive oil from entering between the valve guide and valve stem D Negative pressures in exhaust system and cylinder will draw oil from head area excessive smoking 5 Valve Guides A Installed in the head B Provides the bushing surface for the valve stem 1 Generally made of cast iron or bronze alloys 6 Cylinder head valve seats A Stationary in the cylinder head B Sealing surface for the valve face C Area of wear D Has a45 or 46 degree angle E 0 8 1 5 mm 0 032 0 060 inch width F High alloy steel Includes Nickel generally 2 5 G Normally has at least three angles cut into the seat to all for bet
42. area What is crankshaft throw e It s the distance from the centerline of the main journal to the centerline of the connecting rod journal 1 2 the stroke 29 30 31 32 33 34 35 36 How is the stroke of the crankshaft determined e Throw x 2 Stroke What are the 2 types of crankshaft design e One piece e Multi piece What type of crankshaft is normally rebuildable e Multi piece both in reality What must be done to a multi piece crankshaft after assembly e IJt must be trued What are 2 purposes of the crankshafts counterbalance weights e Adds momentum to the crankshaft e Used to counterbalance reciprocating masses What is the difference in piston movement between a 180degree crankshaft twin cylinder engine and a 360degree crankshaft twin cylinder engine e 180 degree Pistons move in opposite directions e 360 degree Both pistons move together A 120 degree crankshaft in an engine that has e 3 or 6 cylinders What are 3 types of crankcase design e One piece e Vertical split e Horizontal split 4 Stroke Opening Closing Devices 10 11 12 Name 2 types of valve closing devices e Coil Spring e Desmodromic Name 2 types of coil springs used as valve springs and a brief description of each e Straight rate spring has proportional spring rate each coil is the same distance apart e Multi rate spring has 2 rates starting soft and finishing hard 2 differe
43. base oil only 3 SB Medium conditions has anti foaming agents and detergents 4 SC Meets 1964 through 1967 manufacturer requirements NOVEMBER 16 17 1999 PAGE 4 5 SD Meets 1968 through 1971 manufacturer requirements 6 SE Meets 1972 through 1979 manufacturer requirements 7 SF Meets 1980 through 1989 manufacturer requirements 8 SG Meets 1990 through 1993 manufacturer requirements 9 SH Meets 1994 through present manufacturer requirements 10 SJ Not recommended for use in motorcycles 4 Lubricating systems for four stroke engines A Types of storage systems e Wet sump e Dry sump 1 Wet sump systems e SEE FIGURE 7 4 a Oil is stored in the crankcase b A pump is used to force oil through the engine c Oil is gravity fed back to the sump 2 Dry sump e SEE FIGURE 7 5 a Oil is stored in a remote tank b Uses two pumps 1 Feed pump la Used to circulate the oil from the tank and through the engine 1b Must have a check valve to prevent gravity from filling the crankcase when the engine is not running wet sumping 2 Scavenging pump la Used to pump the oil from the engine back to the oil tank NOVEMBER 16 17 1999 PAGE 5 lb Usually has twice the flow capacity of the feed pump B Parts of the lubricating system 1 Oil pumps a Purpose To pressurize the oil and circulate it to the required parts of the engine b Three common types 1 Rotor Trichoidal Star shaped outer rotor and a fou
44. bearing iii races press to different depths see service manual 1988 to current pinion shaft i Pinion shaft is straight no splines ii Pinion gear is light press fit and keyed to shaft 1 Reduces gear runout better cam fit iii New pinion gear iv Nut has NO locktab so use locktite and torque to specs Breather system 4 speed a b Same as alternator iron XL engine i Plastic baffle ii Umbrella valve Small hole under the valve to relieve oil buildup at breather i Hole must be open or air cleaner will get oil Oil pump 4 speed a b c d e f g Operation is the same as 77 pump Feed gear height 0 001 0 011 above pump cover Feed gears were enlarged to supply lifters i Return gears are still larger than feed Gear clearance inner and outer gear i Wear limit 0 004 ii Use shaft to center gears in body Seal lip numbers side toward feed side Oil pressure i Measure at the top plug in the case or the sending unit on the filter housing 1 Factory specs 1 7psi at idle and 5 30psi at 2500 rpm 2 If taken at the sending unit readings will be double Oil flow i Flows from oil tank to the pump cover ii iii iv v vi Feed gear pressurizes oil through small hose to housing 1 Special hoses 2 different fitting sizes no sealant needed Oil filter adapter housing 1 Pressurized oil to adapter housing 2 Enters adapter through drilled holes and fills
45. both types bleed and primary e Hooded and have several air bleed holes NOVEMBER 22 1999 PAGE 5 e Allows for good atomization and throttle response e Air bleed passage or air bleed jet e Purpose Aids in atomization of fuel e Used for mid range and main jet circuits C Main jet circuit 1 Range to wide open throttle WOT 2 Main fuel jet e SEE FIGURE 8 11 a Located in series with the needle jet and the jet needle b After throttle to full throttle main jet is unrestricted 3 Air bleed passage or air bleed jet END OF MECHANICAL SLIDE CARBURETORS NOTES THEORY NOTES SUBJECT Metric system AKA system international KEY POINTS 1 System based on tenths 2 Uses prefixes to indicate the value of each unit to measure 3 Prefixes are A KILO 1000 B HECTO 100 C DECA 10 D UNIT OF MEASURE E DECI 0 1 F CENTI 0 01 G MILLI 0 001 4 Commonly used units of measure A Meter Unit of measure for distance or length B Liter Unit of measure for volume C Gram Unit of measure for weight D Kilogram Centimeter2 Unit of measure for pressure E Kilogram Meter Unit of measure for torque 5 To convert within the metric system multiply or divide by increments of ten A Examples 1 mm 100 divided by 10 10cm NOVEMBER 4 1999 PAGE 2 2 cm 10 times 10 100 mm B Aneasy way to convert within the metric system is to count the number of places moved on the list prefixes and note the direction Mo
46. by the manufacture 3 Never use 100 ethylene glycol ethylene glycol is a very poor coolant when used alone 4 Anti freeze ethylene or propylene glycol la Lowers the freezing point of water to less than 30 degrees water is 32 degrees Fahrenheit lb Raises the boiling point of water to more than 225 degrees water is 212 degrees Fahrenheit lc Contains lubricants anti foaming additives and corrosion inhibitors f Distilled water 1 Better than drinking water because it does not contain mineral deposits that could cause corrosion 2 Better heat transfer properties than anti freeze g Radiator fan 1 Usually an electric fan that is controlled by a temperature sensor 2 Only operates when the engine reaches a pre determined temperature 3 Purpose To draw air through the radiator 4 Fan may or may not be wired through the ignition switch main switch END OF COOLING SYSTEM NOTES NOVEMBER 4 1999 THEORY NOTES SUBJECT Engine Math KEY POINTS 1 Cylinder Volume CV The volume of one cylinder A Formula CV bore X bore X stroke X 0 7854 B Metric 1 Metric unit for measuring volume is cubic centimeters cm3 2 Bore and stroke must be converted to centimeters 10 millimeters mm 1 centimeters cm 3 Metric example a Bore 89 mm Converted to centimeters 8 9 cm b Stroke 91 mm Converted to centimeters 9 1 cm c CV 8 9X 8 9 X 9 1 X 0 7854 566 125 cc C English standard example 1
47. can be done by an engine over a period of time END OF PHYSICAL LAWS NOTES NOVEMBER 10 1999 THEORY NOTES SUBJECT PRIMARY DRIVES KEY POINTS 1 The primary drive is a gear reduction system that transfers power from the crankshaft to the clutch outer basket 2 Methods of transferring power e Gear e Chain e Belt A Gear driven primary drives e SEE FIGURE 6 5 1 Types of gears used a Spur e SEE FIGURE 6 1 b Offset spur c Helical e SEE FIGURE 6 1 2 Uses two gears that turn in opposite directions 3 Clutches usually turns in opposite direction of engine 4 Must be lubricated in an oil bath B Belt driven primary drives e SEE FIGURE 6 7 1 Uses a gilmer type belt which is a toothed belt and a pair of toothed pulleys 2 Both pulleys turn the same direction NOVEMBER 10 1999 3 Operates quietly 4 Must be kept dry and clean C Chain driven primary drives SEE FIGURE 6 6 1 Uses a chain and two gears 2 Both gears turn the same direction 3 Types of chains used a b c d Single roller Duplex roller double row Triplex roller triple row Hy vo 4 Must be kept lubricated 3 Insome cases a primary shaft is used in the primary drive A Crankshaft drives the primary shaft B Primary shaft drives the clutch C Purposes 1 Change direction of rotation 2 Operates a charging system 3 Assists the electric starter system 4 Provides for a shock hub damper in t
48. cooling systems are e Internal cooling e Air cooled e Liquid coolant cooled A Internal ail cooled 1 All motorcycles have internal oil cooling 2 Components systems of internal oil cooling a b e f Oil Oil coolers some motorcycles Oil pumps Oil filters Oil passages and lines Sometimes Oil pressure indicators and or oil level indicators B Aircooled SEE FIGURE 7 12 1 Cylinder heads and cylinders use fins to dissipate heat to the surrounding air NOVEMBER 17 1999 PAGE 2 2 Two methods a Open Draft Movement of the motorcycle forces air over the fins b Forced Draft The engine driven fan draws air through duct work called shrouds Shrouds surround the cylinder and the cylinder head C Liquid coolant cooled e SEE FIGURES 7 10 and 7 11 1 Operation a Coolant is pumped through the water jackets then through the cylinder head and cylinder b Heated coolant then flows through a radiator to dissipate the heat to the surrounding air 2 Cooling systems can be pressure tested for leaks using a coolant system pressure tester to be sure that the system holds a specified pressure for a required amount of time a See service manual for specifications b If the system fails the test 1 Check the hoses and pipe connections 2 Check the water pump installation and seal 3 Components a Pump 1 The engine driven pump is used to circulate coolant 2 It draws coolant through the wa
49. e SOLID e LIQUID e GAS A Solids have three dimensions length width and depth that can be measured B Liquid Characteristics 1 Has no definite shape 2 Conform to shape of container 3 Can transmit pressure 4 Will not expand to fill container 5 Heavy for equal volume of gas 6 Non compressible 7 Other things that can happen to liquids a Atomization 1 Liquid drops suspended in air OCTOBER 27 1999 PAGE 2 2 Still a liquid must be vaporized to burn b Vaporization 1 Liquid converted to a gaseous state requires heat 8 Liquid Flow Rate a How fast a liquid flows Affected by 1 Path of flow The steeper up hill the slower it will be if at all 2 Pressure pushing flow 3 Temperature of fluid 4 Viscosity 9 Viscosity measurement of a fluids liquid or gas resistance to flow 10 Viscosity Index a Number that indicates the viscosity constancy of the fluid at a controlled temperature through a control orifice under a controlled pressure b For motorcycle service the viscosity index is mostly used in relation to oil 1 SAE 10 w 40 la SAE stands for the Society of Automotive Engineers 1b The 10 stands for 10 weight at 0 degrees Fahrenheit lc The 40 stands for 40 weight at 210 degrees Fahrenheit c Higher the number the more resistance to flow and usually the thicker the liquid C Gas 1 No definite shape 2 Conforms to shape of container 3 Can transmit pressure 4 Will expand t
50. end to left lock and let go front end should swing past center twice and stop somewhere near center tech 2 Tech 2 B All other models except springer use 1 2 fall away method 1 disconnect clutch cable and any other restrictive cables 2 support vehicle evenly off of the ground 3 put front end in balanced position 4 set pointer for reference and move front wheel to the left and than to the right a note where the front end falls away in each direction 5 left and right fall away marks should be 1 2 apart REAR SUSPENSION 1 There should be no noticeable side play in rear fork 2 There are several types of rear fork bearing designs A Tapered bearings require grease and adjustments B Solid stainless plug and Teflon bushing requires no service C Silicone rubber clevblock design requires no service 3 Always check torque specs on any fasteners 4 4 speed swing arm bearing adjustment proceedure A Remove everything from swing arm and let it hang free B Connect fish scale to axle C Lift swing arm with fish scale check weight 12 15 Ibs D Torque pivot bolt to increase weight by 2 pounds AIR ASSISTED SUSPENSION 1 FLT FLHT FXRT moselshave front and rear sysstems A Always check manual during service with no loss air gauge see manual for specs B Check for leaks in 2 ways 1 loss of pressure as read on gauge 2 using soap and water 2 Anti dive check A Hold front brake ignition off
51. equal but opposite sides of dead center 2 Example a Intake opens at 51 degrees BTDC and closes at 51 degrees ATDC E A Symmetrical port timing 1 Port opens and closes on unequal sides of top dead center 2 Example a Intake port opens at 72 degrees BTDC and closes at 32 degrees ATDC 8 Two stroke induction systems A Methods of how air fuel and oil enters the primary area e Piston port e Cylinder reed valve e Rotary valve e Crankcase reed NOVEMBER 5 8 1999 PAGE 6 e Piston port Crankcase reed 1 Piston port a Oldest and simplest in design b Intake port is located on the cylinder lowest port in the cylinder c Opening and closing of the port is controlled by the location of the piston skirt and has very little restriction to air flow d Has the narrowest power band of all two stroke engines Engine can be tuned to a low or high RPM range but not both e If engine is tuned to a high RPM and operated at low RPM spit back through carburetor will occur 2 Cylinder reed valve e SEE FIGURE 5 1 a Intake port is located on cylinder same location as piston port b Air flow through port is controlled by pressure differences and a reed valve one way air valve c Port never closes port duration is 360 degrees d Purpose To broaden the engine s power band 1 Allows the engine to be tuned to a high RPM 2 Prevents spit back through the carburetor at low RPM s e Reed valve material 1 Steel stainless
52. for increased volumetric efficiency D Cylinder head functions OCTOBER 29 1999 PAGE 2 1 Aids in heat transfer a Finned for air cooling b Many have passage ways water jackets for liquid cooling c Provides placement for valves spark plugs cams and valve opening and closing devices d Creates a squish area 2 Poppet Valve textbook page 44 A Tulip shaped valve mushroom shaped B Opens and closes every other crankshaft revolution 1 Example 83 times per second 10 000 RPM C Functions 1 Valve opening and closing controls the flow of gases 2 Forms a seal in the combustion chamber approximately 800 1 000 PSI 3 Transfers heat approximately 2 500 degrees Fahrenheit D Material valves can be made from are can be multiple pieces 1 Stainless steel 2 Carbon steel 3 Titanium 3 Valve parts e See figure 4 31 A Tip 1 Area that rides against valve opening device 2 Most are stellite plated for wear 3 Check tips for cupping and other wear 4 Stellite coating very hard metal alloy applied to most valve faces and tips a Prolong the life of the valve OCTOBER 29 1999 PAGE 3 b Replace lead coating from leaded gasoline B Keeper Groove 1 The groove where keepers lock the valve and spring retainer in place 2 One of the wear areas often overlooked C Stem 1 Thrust surface for the valve guide 2 Major wear area 3 If the stem is worn excessive amounts of oil will pall between the stem
53. hotter and has more mass d Requires more piston to cylinder clearance e May have a positive dome flat top or negative dome f May have fly cuts for valve relief 2 Ring grooves a Purpose To allow for ring installation b Bottom ring groove has holes or slots to allow for oil return that 1 Helps remove oil from the cylinder wall 2 Helps lubricate the wrist pin 3 Ring land Upper and lower sealing and support surface for the piston rings 4 Skirt a Load bearing surface of the piston b Contacts the cylinder wall c Largest diameter of the piston is usually at or close to the bottom of the skirt 90 degrees from the wrist pin e SEE FIGURE 4 38 d The piston is usually measured on the skirt 5 Wrist pin boss a The thick area of the skirt b Connects the piston to the connecting rod c Expands a great deal due to the amount of mass d Wrist pin bosses offset NOVEMBER 2 3 1999 PAGE 5 1 Usually offset from the centerline of the piston 2 Creates a major and minor thrust surface 3 Helps reduce piston slap e SEE FIGURE FROM WORKSHEET 4 Piston rings e SEE FIGURE 4 37 4 40 AND 4 39 A Purposes 1 Transfers heat from piston to cylinder walls 2 Seals combustion gasses 3 Prevents excess oil combustion B Types 1 Compression ring a Closest to the piston crown b Seal most of the combustion gasses c Usually made of cast iron d Sometimes they are chrome plated Teflon or molly coated
54. is square 66B part number if o ring seat is beveled b specs shaft to arm 003 max clearance shaft 0015 max wear shaft to box 002 max clearance 1 excessive clearance in these areas will cause flooding of the valve pocket area c see hand out page 3 1 for additional information G Pushrod 1 all 4 identical 2 inspect for a damaged ends b damaged locknuts c max bend 010 H Pushrod Tubes 1 79 and earlier cork gasket flat edge tube 2 L79 84 1 2 o ring gasket lip edge tube for more compression use cork in place of middle o ring CYLINDER HEADS A Specs 1 head gasket surface max warpage of 006 2 head gasket types Teflon blue Graphite black Metal fiber gray James gasket with metal fire ring and silicon bead Install all gaskets dry 3 torque 55 75 ft lbs staged 30 45 55 always start next to oil hole DO NOT GO OVER 65 FT LBS TOTAL ALUMINUM 4 fire ring height causes leaking or blown head gasket when excessive 010 clearance between head and cylinder 5 head bolt should be assembled with lube or never seize 6 additional information on page 3 2 of hand out B Cylinder prep for re assembly 1 clean in soapy water 2 clean and lube with a paper towel and motor oil light weight 3 clean drain hole with a brush C 1980 heads 1 cast iron guides longer with shoulder 2 head has machined surface for new style lower valve sprin
55. long sheilded 3 8 allen socket remove all 5 sprocket bolts D Connect a ratchet strap to upper shock mount and swing arm remove lower shock bolts lower swing arm enough to remove brake caliper anchor bolts E Pull axle 3 4 of the way out F Lift out caliper and hanger and secure out of the way G Deflate tire seperate wheel from sprocket tilt wheel carefully remove caution be careful of inner spacer falling out of wheel Installation Reverse order of removal Don t forget the inner spacer Clean and lubricate bolts Torque sprocket bolts to 65 75 ft lbs cross pattern Torque axle to 60 ft lbs Readjust caliper anchor bolts Mount mufflers forward on bracket Inflate tire Pump brakes Ammo nws TOMMOUOWS 2 Transmissions and Final Drives 10 11 Ie What is the purpose of the motorcycle transmission e To change the speed of the motorcycle e To keep the engine within it s useable powerband Motorcycles use constant mess transmissions Define Constant Mesh e Teeth of all gears mesh with their mate on the opposite shaft at all times What types of gears tooth design do most motorcycle transmissions use e Spur What are the 3 gear to shaft designs used in motorcycle transmissions e Fixed gears e Freewheeling gears e Slider gears How can a fixed gear be fastened to the shaft e Machined on e Pressed on e Splined on What is the purpose of the sliding gear e Engage and lock freewhee
56. needle jet NOVEMBER 18 1999 THEORY NOTES SUBJECT Air Density KEY POINTS 1 Air Density A The amount of oxygen molecules per given volume of space 2 Effect of changes air density available oxygen air fuel mixture ratio Increases Increases Leaner Decreases Decreases Richer 3 Factors affecting air density A Humidity Higher humidity results in a lower air density B Temperature Higher temperatures will decrease air density C Altitude An increase in altitude will result in a decrease in air density 4 Possible result and correction for air density changes air density carburetor jetting suggested service Increases Becomes to lean Changes jets to larger size Decreases Becomes to rich Changes jets to smaller size 5 Most carburetors can tolerate a broad range of air densities and rejetting is not usually required on street motorcycles for normal riding END OF AIR DENSITY NOTES NOVEMBER 19 1999 THEORY NOTES SUBJECT Air fuel delivery systems and related components e SEE FIGURE 8 1 KEY POINTS 1 Purpose A Before carburetor components Store and deliver proper amounts of air and fuel to carburetor or fuel injector B After carburetor components Deliver air fuel mixture to the engine 2 Common components A Fuel tank 1 Purpose To store fuel 2 Vented to the atmosphere Some states example California require fuel tanks to vent into charcoal canisters 3 Usually rubber mounted 4 Must b
57. on the opposing shaft at all times B The housing is vented to the atmosphere C Sealed around the shafts D Lubricated 3 Gear designs A Spur straight cut gears Most common B Helical angled teeth gear Next most common C Beveled spur or helical left or right side taper 4 Three gear to shaft designs A Fixed gears 1 A gear that can not move on the shaft 2 Rotates at shaft speed 3 Fixed either of 3 ways a Machined to the shaft b Splined to the shaft c Pressed on the shaft NOVEMBER 15 16 1999 PAGE 2 B Free wheeling gears 1 2 3 4 A gear that free wheels on its shaft Held in place with circlips usually Does not have to rotate at shaft speed Freewheeling gears will have slots or dogs on its side C Slider gears 1 2 3 4 5 6 7 A gear that can slide across the axis of the shaft Most are splined to the shaft and rotate at the speed of the shaft Slider gears are moved across the axis by use of a shift fork The purpose of the slider gear is to engage and lock the freewheeling gear to its shaft Slider gears have protrusions on the sides known as dogs Slider gears engage freewheeling gears by the use of dog to dog or dog to slot For a constant mesh transmission to operate properly a freewheeling gear has to be opposed to a fixed or slider gear 5 Transmission types Indirect drive Direct drive Dual range sub transmission A Indirect Drive Transmi
58. over size B M 77 85 caged bearings C to change early countershaft free bearings to caged you need 1 late cluster gear 2 late countershaft threaded 2 groove or notched 3 late case races D throw out bearing 1 36 M 75 automobile style bearing best style 2 M 75 85 wafer style bearing takes the same load as auto style bearing won t live with a constant load clutch adjustment is critical has a sheet metal oil slinger Harley Davidson Tech 1 1 Intro Dates a 883 started in early 1986 to present b 1100 started in late 1986 to late 1987 c 1200 started in early 1988 to present Case breather sportsters from 1986 1990 Iron sportsters from 1957 1985 2 3 4 5 6 7 8 9 Compression Ratio a 9 1 on ALL models Rocker covers a Big Twins B T and Sportsters XL can be interchanged as a set i Topend breather covers must be used on top end breather motors ii Print o seal gasket and inner cork or rubber chimney are the same for B T and XL iii All rubber gaskets from late 1989 till current iv XLrocker arms and shafts are the same as the B T Rocker arm play is 0 003 to 0 013 between rocker arm and rocker box endplay Bolts are hardened and CANNOT be replaced or mixed with unhardened bolts Rocker shaft to Rocker box clearance for all XL s is 0 0007 to 0 0022 ID to OD clearance 9 16ths 18 tap is used to push out rocker arm bushings from the opposite
59. pressure oscillations inside the cylinder that produce the sharp metallic noise called knock e Pre ignition and detonation result in increased combustion chamber temperatures f Engine design features that determine whether normal or abnormal combustion occurs 1 Compression ratio combustion chamber design 2 Engine load 3 Fuel quality turbulence 4 State of tune OCTOBER 27 28 1999 PAGE 4 C Results of combustion 1 Heat and power produce work a Cylinder head temperature of approximately 300 to 375 degrees Fahrenheit 1 Most engines run at lower temperatures b Combustion gas temperatures as high as 4 000 degrees Fahrenheit in the combustion chamber c Cylinder pressure reaches 800 to 1 000 PSI d Heat expands nitrogen gas in the combustion chamber and pushes the piston toward BDC 2 Chemical changes resulting in a Carbon Monoxide CO Partially burned fuel Fuel not completely burnt during the combustion process e CAUTION Carbon Monoxide is colorless odorless poisonous and deadly b Hydrocarbons HC Unburned fuel raw fuel c Carbon Dioxide CO2 Results from complete combustion d Oxides of Nitrogen NOx Oxidized nitrogen resulting from extremely high combustion chamber temperatures e Water H20 Results from complete combustion For every gallon of fuel burned approximately a gallon of water is produced in a vaporized form f Heat Resulting from the chemical cha
60. purposes of the intake manifold e Deliver air fuel to the engine e Secure the carb to the engine e Make up the intake tuned length Name 3 types of carb mounts and briefly describe each e Spigot carb fits inside manifold boot e Flange carb bolts directly to the head e Clamp on carb fits over manifold boot Batteries 1 Purposes A Provide initial power to start motorcycles and run accessories when engine is off B Provide energy when engine is idling C Buffer out voltage surges spikes captive action 2 How A Stores electrical energy in chemical form B Upon request converts chemical energy back to electrical energy C This electrochemical change is NOT 100 efficient 3 Types of Batteries found on motorcycles A Conventional 1 Paper of fiberglass separators 2 Fewer total plates 3 Requires frequent water replacement B Low maintenance 1 Separators of thinner denser synthetic material 2 More total plates 3 More cranking power 4 Less frequent water replacement C Maintenance free 1 Recombinant technology 2 Special plates and electrolyte 3 About the same cranking power as a low maintenance 4 Permanently sealed no water replacement required 4 Battery Cells A Each cell stores 2 1 2 2V B Construction 1 negative plates a lead b Grey in color 2 positive plates a lead peroxide b reddish brown in color 3 separator sheet a porous material b insulates the negative and positive plates f
61. skirt to help lubricate exhaust port bridge D Two stroke pistons are taper and cam ground similar to 4 stroke pistons 4 Piston rings e SEE FIGURE 5 8 A Purposes 1 Seal the secondary and primary area 2 Transfer heat from the piston to the cylinder B Types 1 Standard a Rectangular in shape b Cheapest to manufacture c Most common 2 Keystone a Wedge shaped b Seals better than standard c More expensive to manufacture d Must fit into a wedged shaped groove 3 Dykes a L shaped b Used only as a top ring c Best sealing and heat transfer NOVEMBER 8 9 1999 PAGE 4 d Most expensive to manufacture 5 Connecting rods A Purpose 1 A lever that transfers power from the piston to the crankshaft B Most 2 stroke engines will use a one piece connecting rod with 1 A roller bearing at the big end 2 A needle bearing at the small end C Two stroke connecting rods will have slots or holes at both ends to allow for lubrication 6 Crankshafts A Purpose 1 To change a reciprocating motion into a rotary motion B Most two stroke engines will use a multi piece crankshaft C Most two stroke engines will use ball bearings on the main journals D Multi cylinder crankshafts 1 For multi cylinder engines each cylinder must have its own primary area sealed from each other 2 Todo this a labyrinth seal is used a All metal seals b Stationary and does not touch the journal c Has very close clearance to
62. space rcollar should have end play a check oil pump drive gear installation install so 1inner chamfer faces flywheels 3 oil pump drive gear 66 72 5 tooth 73 84 6 tooth 4 oil pump driven gear 66 72 25 tooth 5 1 ratio 73 84 24 tooth 4 1 ratio better can retro fit as a set O Gear case cover 1 66 69 peanut style 2 70 72 cone style one shot oil flow 3 73 84 cone style full flow oil flow P Torque pattern for cam cover installation Q Cam timing 8 LOWER END A commonized and pre communized parts hand out page 2 16 commonized parts L81 and later service bulletin M829A 1 reason for change more economical to manufacture and better fit at taper commonized pre commonized pinion shaft 90 degree to keyway 135 degrees right side flywheel crankpin rear cyl advance lazy 8 no lazy 8 B Changes to crankpin after commonized 1 L81 L82 140 center oil hole 2 L82 84 090 center oil hole 3 84 and up large offset oil hole C Connecting rods 1 41 73 long rods no longer available if old style pistons are retained for use with new style short rods a piston to flywheel clearance must be checked at BDC should be 1 8 min b compression ratio will be reduced from 8 1 to 7 6 1 2 74 82 short rods with slot 030 shorter center to center 3 82 E83 short rods with hole 4 L83 84 short rods offset
63. system for the crankshaft to the clutch outer basket 2 Crankshaft is the drive 3 Clutch outer basket is the driven 4 Gear ratio Crankshaft 24 teeth drive Clutch basket 68 teeth driven 68 divided by 24 2 83333333 so the gear ratio 2 833 1 B Transmission 1 Transmit power from clutch to final drive usually a Main shaft is usually the drive shaft b Countershaft is usually the driven shaft 2 Formula to calculate gear ratio in most cases a number of teeth on countershaft divided by number of teeth on the main shaft b Examples 1 Main shaft gear 16 teeth and countershaft gear 44 teeth 44 divided by 16 2 750 so the gear ratio 2 750 1 3 Transmission gear ratio can be calculated in any gear C Final drive 1 Purpose To transmit power from the transmission to the rear wheel a Transmission output is the drive b Rear wheel sprocket is the driven NOVEMBER 9 10 1999 PAGE 6 2 Formula to calculate gear ratio a Chain drive e SEE FIGURE 6 6 1 number of teeth on rear wheel sprocket divided by number of teeth on transmission sprocket gear ratio 2 Example Transmission output 13 teeth and rear wheel sprocket 40 teeth 40 divided by 13 3 076923077 so gear ratio 3 077 1 b Shaft drive 1 number of teeth on ring gear divided by number of teeth on pinion gear ratio 2 Example Pinion gear 13 teeth and ring gear 52 teeth 52 divided by 13 4 so the gear ratio
64. that relates air velocity to air pressure B Ina tube air velocity is inversely proportional to pressure C Application As air velocity increases the relative pressure inside the tube will decrease D Relative pressure is the force pushing on an object 2 Venturi Constriction within a tube e SEE FIGURE 8 10 A Location Inside the throat of the carburetor B Purposes 1 Increase air velocity 2 Decrease pressures in the carburetor throat 3 Allows atmospheric pressure to push the fuel from the float bowl into the carburetor throat 4 Effect of venturi size A Carburetors are sized by their size of the venturi 1 Larger than stock venturi a Allows for a better performance at high RPM range b Sacrifices mid range and low end torque 2 Smaller than venturi a Allows for a better throttle response in low RPM and mid range b Sacrifices peak horsepower NOVEMBER 19 1999 PAGE 2 5 Carburetor venturi designs A Variable venturi carburetors 1 Venturi sizes varies by changing the position of the slide 2 Two major categories a Mechanical slide throttle control b Constant velocity sometimes called constant vacuum B Fixed venturi carburetors venturi size is constant no slide END OF VENTURI EFFECT AND DESIGN NOTES Oils and Lubrication Systems 1 What are the 4 main purposes of lubricating oil e Clean e Cool e Seal e Lubricate 2 Where does the Base Stock used to make engine oils come from e Mi
65. that traps dirt 2 When dirty clean in warm soapy water rinse and dry 3 Oil the air filter with oil made for gauze 3 Do not substitute one filter for one of a different construction This can create a lean or rich condition I Intake manifold 1 Purposes a Delivers air fuel mixture to the engine b Secure the carburetor to the engine c Makes up the intake tuned length 2 Types of carburetor mounts are a Spigot 1 The carburetor body fits inside the rubber intake manifold 2 The clamp holds it in place b Flange mount 1 The carburetor body has mounting points cast into it 2 The mounting points bolt to the intake manifold a Clamp on 1 The carburetor body has a clamp casted into it 2 The carburetor body fits over the intake manifold END OF AIR FUEL DELIVERY SYSTEMS AND RELATED COMPONENTS NOTES NOVEMBER 18 1999 THEORY NOTES SUBJECT Air fuel mixture requirements KEY POINTS 1 Air fuel mixture ratio A A ratio indicating by weight the parts of air compared to one part of fuel B Example 15 1 air fuel mixture ratio means 15 parts of air to one part of fuel by weight C General guidelines 1 Theoretical perfect combustion occurs at 14 7 1 ratio stoichiometric ratio 2 Lean air fuel mixture occurs at ratios above 14 7 1 PSI 3 Rich air fuel mixture occurs at ratios above 14 7 1 PSI 2 Riding conditions A Cold start 1 Requires a very rich mixture of 10 1 or less 2 Reason Cold engi
66. the drive plates Power flow stops at the drive plates NOVEMBER 10 12 1999 PAGE 5 Outer clutch basket and drive plates free wheel on the transmission main shaft 8 Common problems a Clutch slippage Clutch does not transfer 100 of the engines power flow Caused by 1 Improper adjustment too little clutch lever free play 2 Weak clutch springs 3 Worn drive or driven plates 4 Improper clutch assembly 5 Oil contamination of dry clutches b Clutch drag clutch will not fully disengage Caused by 1 Warped metal plates 2 Worn outer basket 3 Worn inner hub 4 Improper adjustment of the clutch release mechanism 5 Worn clutch release mechanism 9 Clutch release mechanisms a Purpose to engage and disengage the power flow from the engine to the transmission 1 When the clutch is disengaged the clutch release mechanism pushes the pressure plate separating the drive and driven plates 2 Clutch must be engaged gradually b Two types 1 Inner pressure plate 2 Outer pressure plate c Throw out bearings are used to reduce friction between the push rod and the pressure plates d Types NOVEMBER 10 12 1999 PAGE 6 1 Rocker arm release e SEE FIGURE 6 11 2 Ball and ramp release e SEE FIGURE 6 12 3 Rack and pinion release e SEE FIGURE 6 13 4 Lever release e SEE FIGURE 6 14 5 Cam release e SEE FIGURE 6 15 6 Screw release e SEE FIGURE 6 16 7 Hydraulic release e SEE FIGURE 6 17 B Centrifugal
67. to oil d oil leaks i tappet block to case oil will be grungy ii small o ring to case oil will be dirt free possible that the counterbore is to deep in the case should be 0 050 0 060 18 19 20 wm ma e iii shim up with a small washer iv use Hylomar to seal Torque to 15 18 ft lbs Gearcase cover a b c d Bolt torque patterns given in Tech Tips 25 2 dowel pins are for centering cover computerized sizes for gear fitment i quadrex room temp of 68 degrees ii measures center to center of bushings down to 0 00000 hundred thousandths iii prints sheet telling what cams to use iv production covers have no markings but information is on file at HD v P amp A covers are color coded for correct cam selection 1 PN 25488 86 cover with cams and pinion gear T cams 2 Cover only retrofits all alternator covers 84 1 2 Service of gearcase area i Replace cover order cover and cams as a set ii Replace bushings 1 Must line ream Cams a b 1986 1987 T cams i same cam in 883 and 1100 ii dogbone installed with the chamfer facing cam out 1988 1990 C cams i same cam used in 883 and 1200 ii reduced emissions iii dogbone installed with chamfer facing cam out flywheels a b c d e 3 piece flywheels i 1 piece flywheel halves ii no retrofit except left side wheel from pre comonized to comonized mu
68. washer under nut don t damage o ring part of cable no seperate part number some cables leak at crimped area replace 88 clutch cable Om mo Aw gt A B C D 1 o ring at end 2 adjustable in middle of cable 3 88 primary cover changed for o ring 4 cable will retro fit to 86 Clutch adjustment disconnect battery slacken clutch cable all the way remove clutch screw lock and spring turn counterclockwise until firm turn clockwise 1 4 to 1 2 turn replace screw lock and spring adjust cable for1 16 cable freeplay Primary chain adjustment disconnect negative battery terminal take out slack in primary chain rotate wheel to find tight spot adjust to 3 8 to 1 2 slack Oil level and type A A B C D A B H D sport transmission fluid 1 designed for higher loads 2 retrofits all wet clutches 4speed 1 24 oz measured 2 fluid should just dribble out of level plug with motorcycle upright 5 speed 1 32 oz measured or just up to diaphragm spring on clutch Cover removal disconnect battery release chain adjuster remove clutch screw nuts remove fasteners Clutch release powdered metal M 923 late model parts 1 angle of ramp and coupler changed helps prevent breakage caused by misalignment C retro fits as set to 84 1 2 Motor sprocket and chain same since 57 A torque to 150 160 ft lbs use Loctite 242 B use lock link tool to hold sprocket M
69. when contact cleaner is sucked in DO NOT SMELL EXHAUST IT WILL RESULT IN DEATH C Commercial tools for air leak detection are snap on propane leak detector electronic air leak detector tech 2 Tech 2 PRIMARY DRIVE always have battery disconnected before opening primary drive 1 Inspection A tight spots check chain slack all the way around more than 3 8 differance between tightest and loosest spot replace chain B corrosion link damage or heat damage replace chain C inspect adjusters for excessive wear fastener tightness and bracket condition D oil levels XL on sheet FL 65 84 1 2 none 2 adjustment A XL 3 8 5 8 chain link height use inspection cover B Big twin 5 8 7 8 FINAL DRIVE 1 Inspection A Replace any chain that shows 1 any rust between rollers and side plates 2 has battery acid corrosion 3 has more than 1 2 differance between tight and loose spots 4 has roller or side plate damage 5 measures longer than 12 7 8 for 20 links 6 has kinks B Replace any sprocket that shows wear 1 teeth should almost have square teeth no hooks or fins 2 Adjustment Always adjust at the tightest spot Measure chain alignment With axle alignment tool measure swing arm pivot to axle distance With alignment tool attached to chain at rear sprocket check alignment of chain to gauge E By sighting chain for alignment between sprockets chain deflection is checked at bottom strand F F
70. with hole dog leg rods 10 times the fatigue resistance reduces bend and twist wider web on female rod requires new flywheels with relief 9 Oil pump A oil type 1 40 degrees and lower 10 40 multigrade 2 40 80 degrees 20 50 multigrade 3 80 degrees and up 60 weight extra heavy 4 80 95 degrees SAE 60 5 95 degrees and up SAE 70 B oil pressure 1 measure at operating temperature 180 220 degrees 2 spec idle 3 5 PSI 2000 RPM 12 35 PSI C Feed system 1 gravity feed to F fitting on pump 2 check valve a 2 3 lb spring and ball seals pump and prevents drain down when engine is not running a leaking check valve causes tank drain down and blows oil out of breather on start up a to repair lap seat with bead blasted Evo pushrod end it s the same size as the check ball 3 after engine is running check valve opens and oil flows to tappet screen lifters and top end 4 lower end passasge opens at 5 10 PSI regulating piston moves upward to open passage oil flows through crank case and gear case cover to pinion bushing a oil flows through pinion shaft right side flywheel and crank pin b the oil lubricates the rod bearings c splash from rods lubes the pistons pin bushings and lower end bearings 5 relief passage opens at 12 18 PSI L73 81 oil directed to return side L81 and up directed to feed side relief 6 hydrolocked oil oil trapped above relief piston L73 80 down tower to retur
71. 0 s are red 1991 and later there s a timing mark on right side flywheel 21 Connecting rods 22 23 24 25 wa wm Na wm a Dog legged 1982 and later ALL Evos b Wrist pin clearance is 2 times that of a B T helps prevent seizure c Bearings i Early 1986 were loose rollers with flat thrust washers ii Late 1986 through current use F A G bearings started on day 095 d For the first 2 months no thrust washers were used added late May i Stepped for clearance wider cage e Service just like the B T bearings i 1 bearing size 3 sizes of crank pin Sprocket Shaft a 5 speed shaft is 0 750 longer than 4 speed i Rotor and stator moved to sprocket shaft from clutch shell ii Rotor pressed and screwed to socket Pinion shaft and race a b c 1986 only unitized caged bearing pressed into case i Race pressed onto shaft 1 185 1 195 from flywheel race ii Grind to size 1 2485 1 249 16rms finish 1987 current uses F A G bearing i 3 pieces 1 outer race pressed into case 2 inner race pressed onto shaft 3 separate bearings ii 4 sizes of bearing iii races press to different depths see service manual 1988 to current pinion shaft i Pinion shaft is straight no splines ii Pinion gear is light press fit and keyed to shaft 1 Reduces gear runout better cam fit iii New pinion gear iv Nut has NO locktab so use locktite and torque to specs Breather system 4 spee
72. 000 hundred thousandths iii prints sheet telling what cams to use iv production covers have no markings but information is on file at HD v P amp A covers are color coded for correct cam selection 1 PN 25488 86 cover with cams and pinion gear T cams 2 Cover only retrofits all alternator covers 84 1 2 44 45 46 47 wm wm wa d Service of gearcase area i Replace cover order cover and cams as a set ii Replace bushings 1 Must line ream Cams a 1986 1987 T cams i same cam in 883 and 1100 ii dogbone installed with the chamfer facing cam out b 1988 1990 C cams i same cam used in 883 and 1200 ii reduced emissions iii dogbone installed with chamfer facing cam out flywheels a 3 piece flywheels i 1 piece flywheel halves ii no retrofit except left side wheel from pre comonized to comonized must rebalance b oil restrictor in the pinion shaft c no rear cylinder advance mark d balance factors used to balance at speed higher balance at higher RPM lower lower RPM balance i 1340 60 ii 1100 69 blue iii 883 62 yellow iv 1200 62 white v after 1989 all 883 flywheels are colored green and all 1200 s are red e 1991 and later there s a timing mark on right side flywheel Connecting rods a Dog legged 1982 and later ALL Evos b Wrist pin clearance is 2 times that of a B T helps prevent seizure c Bearings
73. 1 Clutch adjustment data A flat plate shifter wet or dry clutch 13 16 measurement B ratchet top shifter wet or dry clutch 1 2 measurement C 5 speed wet clutch 3 4 turn out 12 AP wet clutch A 84 1 2 89 with 4 and 5 speed transmission B lubricant level bottom of clutch with motorcycle upright and level Derby cover removed fluid to bottom edge of diaphragm spring C type H D primary chain case lubricant 1 1 2 quart change every 5 000 miles D primary housing extra fasteners added for rubber mountin 85 and 86 for rigid mount engines from E 1 printo seal gasket 2 primary vent through mainshaft and transmission vent vent plugged oil leak 3 crankshaft seal installs lip lip side out to keep primary chain case lubricant going into the engine clutch adjustment 1 service set up check at 500 miles than every 5 000 miles 2 proceedure a disconnect battery b apply max slack to clutch cable c loosen clutch screw and locknut d inspect and adjust spring tension 1 spring attitude flat 010 2 spring tension adjustment i back out adjuster plate bolts 1 2 to 1 turn at a time ii note position of bolts A B or C Gii change position as necessary iv replace bolts 1 2 to 1 turn loctite 222 on bolts and torque to 6 5 8 ft lbs e adjust clutch screw 5speed 1 turn in until it touches 2 back out 3 4 turn and tighten locknut f adjust clutch screw 4spe
74. 2 Stroke Cylinders to Crankshafts 10 11 What is the advantage of a centrally located spark plug e Helps reduce detonation How does the squish band work in the 2 stroke cylinder head and why is it used e Helps create turbulence to assist in mixing the air fuel mixture cool the cylinder reduce end gases and also concentrates the charge under the spark plug What is the purpose of the cylinder e Guide the piston travel sealing surface for the rings locate the ports and aid in heat transfer What are 3 types of 2 stroke cylinder construction e Cast Iron e Aluminum w sleeve e Coated aluminum What precautions should be taken when servicing a plated cylinder e Not to remove any of the plating non serviceable Why are some ports in the 2 stroke cylinder bridged e Helps keep the piston ring in the ring groove and not catching on the cylinder port What should normally be done to an exhaust port bridge after boring the cylinder e It should be relieved What must be done to the sharp edges of the port after boring a 2 stroke cylinder e Must be chamfered What is the purpose of the piston e Transfer power to the con rod e Seals primary and secondary areas e Thrust and sealing surface for the rings e Control opening and closing of the ports What are the 2 ways 2 stroke pistons and manufactured e Cast e Forged Why are ring locator pins necessary on 2 stroke pistons e Keeps the rings from rotating and catchi
75. 4 run bike at 3000 RPM and read meter reading should be triple idle 20 vac 2000 rpm 40 vac 3000 rpm 60 vac Current draw 1 set meter with red lead in 10 amp position 2 turn on ignition high beam passing lamp etc except brake light read meter Tech 2 if under 7 amps turn on brake light 3 check total loads against total amps in charging system 4 must have a minimum of 305 amps returning after loads to maintain battery F Regulator 1 ground from shiny edge of fin to to ground should read OL 2 system draw key off 10A scale should read zero 3 disconnect regulator lead at circuit breaker so system drain test again minimal amount of drain ok 4 regulator bleed check each pin should be zero WHEEL R amp R 1 wa tech Key points Do not disconnect chain Remove chain or belt guard Don t remove caliper assembly compress piston by hand and tie up out of the Don t loosen chain or belt adjusters Remove axle slide wheel forward and remove air from tire Remove chain or belt from rear sprocket and remove rear wheel On reinstallation be sure brake pads are aligned properly before inserting brake disc H Recheck adjusters and adjust if necesary chain or belt alignment or tension I Pump brakes until firm check for smooth release 80 84 FLT FXRT rear wheel removal A Raise rear wheel B Remove both saddle bags and mulfflers C Remove plug in tower chain housing use
76. 4 1 D Overall gear ratio 1 Numerical gear ratio from the crankshaft to the rear wheel 2 Generally calculated with transmission in highest gear but can be calculated in any gear selected 3 Formula to calculate overall gear ratio is a unrounded primary ratio X unrounded transmission ratio X unrounded final drive ratio overall gear ratio b Example 1 Unrounded primary ratio 2 83333333 2 Unrounded transmission ratio 0 927 3 Unrounded final drive ratio 3 076923077 4 Overall ratio 2 83333333 X 0 927 X 3 076923077 8 081538461 5 Round to thousandths gear ratio 8 082 1 END OF GEAR IDENTIFICATION RATIOS NOTES OCTOBER 27 28 1999 THEORY NOTES SUBJECT Internal Combustion KEY POINTS 1 Combustion Rapid combining of oxygen with other elements Rapid oxidation is burning A Rust is an example of slow oxidation B Chemical change can result in the release of heat and light when combining with oxygen C Heat will generally hasten chemical changes acts as a catalyst 1 Acatalyst speeds up reaction without undergoing change itself D Cold will usually slow down retard chemical changes 2 Types of engines A External combustion engines 1 Burns fuel outside of engine to heat another substance that provides the mechanical energy 2 Example Steam engines B Internal Combustion engines 1 Burns fuel inside the engines Fuel provides the mechanical energy to run the engines 2 Motorcycle engines
77. 5 69 long electric start 3 70 E 80 longer AC generator 4 L 80 E 84 same length different diameter 5 L 84 85 longest wet clutch B max bend 003 max wear 001 C Ist and 2nd gear fixed pressed on FL early FX and late FX D 3rd gear free wheeler bearing offset causes a little whine steel on steel always replace clip E 3rd amd 4th gear clutch marked high on one side for correct installation dog ramps should angle to point towards rear max backlash 010 F 4th main drive gear free wheeler bushing clearance 004 good 001 002 1 installation of bushing requires a special tool and the direction is important spiral or closed groove end installs toward the seal leave enough room for the seal 1 4 5 16 hone or ream to size 2 endplay L 77 81 0025 0135 M 77 and earlier and 82 85 010 025 Drive gear area leaks A to locate use solvent or kerosene in transmission B areas 1 seal to case 2 seal to spacer polish spacer and check for grooving install new seals pre lube lip 3 spline leaks C 82 85 use p n 11166 o ring to seal splines new spacer p n for use with o ring chain 35079 84 belt 35070 84 D 81 and earlier clean all parts with contact cleaner before assembly 26 Bearing changes A 36 E 77 44 loose roller bearings around main drive gear 1 available in STD 0004 and 0008
78. 9 709 rounded off to 9 7 1 END OF ENGINE MATH NOTES NOVEMBER 16 1999 THEORY NOTES SUBJECT Final drives KEY POINTS 1 Final drives A A gear reduction system that transmits power from the transmission to the rear wheel B Types e Chain e Belt e Shaft 1 Chain driven most common e SEE FIGURES 6 28 6 29 and 6 30 a Uses a single roller chain b Many current motorcycles use an o ring type chain Take care not to damage the o ring located at each plate c Offers a wide range of gear ratio changes by replacing the sprockets d Maintenance requirements 1 Clean and lubricate periodically 2 Proper alignment of sprockets 3 Proper tension of the chain per service manual procedures and specifications 4 If applicable check the master link conditions and installation 2 Belt driven e SEE FIGURE 6 31 a Uses a gilmer belt and a pair of toothed pulleys b Offers a limited range of gear ratio changes by replacing the belt and pulleys NOVEMBER 16 1999 PAGE 2 3 Shaft driven e SEE FIGURES 6 32 and 6 33 a Parts 1 A bevel gear set in the transmission or an output shaft flange 2 Shock hub 3 Drive shaft 4 Slip joint spline and sprocket 5 U joint 6 Ring and pinion gear in the final drive housing b Least efficient of all final drives c Maintenance requirements 1 Change gear oil in the final drive housing sometimes the shaft drive housing as well 2 Clean and lubricate the drive spline at the rear
79. B 73 E 81 boomerang bracket was used tech 2 Tech 2 C L 81 84 Y bracket replaced boomerang D L 80 84 cut groove and put square ring in body no longer in the piston 1 retraction rate 1 undercut determines rate of retraction COMPRESSION TESTING 1 Proceedure A Remove spark plugs and join wires together with 1 plug to prevent arcing and possible fire B Open throttle to wide open position C Turn engine over until compression tester shows less than 5 psi increase per compression stroke D Both cylinders should read within 10 of each other E Most H D engines will produce 100 psi or more 2 Differance of more than 10 between cylinders or compression below 100 psi should be diagnosed A Put 1 tablespoon of motor oil in cylinder and test again 1 psi higher now rings are not sealing 2 psi same suspect valve or gasket sealing problem PUSHROD AND TAPPET ADJUSTMENT 1 see tech 1 notes check pushrod adjustment than run engine and change oil FRONT AND REAR SUSPENSION 1 Check for any loose fasteners check for any damage 2 Check for any noticable dampening 3 Check for any fluid or air leaks FORK STEM BEARING INSPECTION 1 Check for any looseness in bearings 2 Check that front end pivots smoothly A cables should not be binding movement 3 Check adjustment A FLT FLHT swing method 1 disconnect clutch cable from handlebar 2 support vehicle evenly off of the ground 3 pull front
80. Intake port is located on the crankcase b Air flow through the port is controlled by pressure differences and a reed valve c Intake port never closes port duration is 360 degrees d System can develop a very wide power band because 5 1 1 3 more area to add more transfer ports 2 Shorter and more direct intake path e Reed valve prevents spit back at lower RPM s Piston port case reed a Combination of piston port and crankcase reed induction b Piston port controlled intake at lower RPM s c Crankcase reed controlled intake at higher RPM s d Used primarily by Suzuki 9 Advantages and disadvantages of two stroke engines versus four stroke engines A Advantages 1 2 3 4 5 6 Better mechanical efficiency Weighs less Lower center of gravity 2 stroke engines normally produce more horsepower than a 4 stroke of the same size Power stroke every revolution of the crankshaft Many operate at any position depending on carburetion B Disadvantages 1 2 3 4 5 6 7 8 High HC emissions Poor fuel economy Excessive and higher frequent vibration Engine operates at higher temperatures NOVEMBER 5 8 1999 PAGE 9 Excessive noise higher pitch More prone to engine seizure due to less cool down time between power events Narrower power band Less reliable and requires more service END OF TWO STROKE ENGINE THEORY OF OPERATION NOTES THEORY NOTES SUBJECT Valve Open Cl
81. PDI Pre Delivery Inspection see inspection hand out Right rear Right side Right front Left front Left side Left rear Ee p OIL CHANGE PROCEEDURE 1 School vehicles A Drain oil into a clean pan and refill tank with original oil B R amp R oil filter reuse old filter 1 when tightening turn oil filter1 3 1 2 turn after gasket contacts housing C R amp R tappet screens on big twins and clean use modified snap on drag link socket 2 Real world A Drain oil from tank 1 drain hoses where used as early as 83 on XL s 2 all H_D s have a drain plug or drain hose 3 fill to proper level with clean oil B Oil filter always lubricate rubber gasket before installation C Do not install return side oil filter until system has been flushed D 84 and later XI engine is on the fuel side install before starting with filter 1 2 full of oil 3 Refilling system A First refill oil tank with recommended oil B Start engine and run until clean oil exits oil filter housing this flushes old oil out of the lines and crankcase C Always replace drain plug gasket CARBURATION 1 It is illegal to altercarb remove tamper plug A It is legal to 1 adjust slow idle RPM 2 adjust fast idle RPM 3 adjust float level 4 adjust accelerator pump spring tension or pin setting 5 adjust choke spring 6 adjust idle mixture if screw is exposed 2 Idle mixture adjustment tech 2 Tech 2 A Should be performed after igni
82. Produced by the distilling process 1b Not recommended in quantities above 5 MTBE Methyl Tertiary Butyl Ether la A product of crude oil 1b Not recommended in quantities above 15 d Types of oxygenated fuels 1 Gasohol la Gasoline blended with small quantities of alcohol 1b Generally used seasonally mandated primarily from October to February in areas with high CO ratings lc Disadvantages e Its hydroscopic absorbs water e Can harm rubber cork and plastic fuel system parts e Can cause lean air fuel mixture ratios ld Advantages are e Raises the octane rating of gasoline Burns cleaner e Good deicer 2 Reformulated Gasoline RFG la Reformulated gasoline may be better for the environment than alcohol 1b Required year round by federal laws in some areas since 1995 lc The storage life is generally shorter than unleaded gasoline of the past ld To new to verify pros and cons NOVEMBER 18 1999 PAGE 4 e Possible disadvantages May lean out air fuel ratios and may be incompatible with some rubber parts found in older fuel systems e Possible advantages May have superior lubricity than conventional gas B Alcohol as a fuel 1 Not recommended by any manufacturer 2 Does not produce as much heat energy so approximately twice as much is needed for useful conversion to horsepower 3 Alcohol is slower burning which causes a longer ignition lag time 4 Can cause an increase of horsepower of appro
83. Rocker box installation torque pattern Head bolt installation torque pattern Rocker box A Cut out provides clearance between cover and frame when engine is hot 1 engine expands approxamately 040 measured from cylinder deck to top of rocker box B Rocker shaft location 1 degree negative angle places rocker arm lower on valve side spins valve to prevent lead build up quieter supposed to keep arm thrusted to one side C Gasket torque to 12 15 ft lbs 300 percent increase when engine reaches operating temperature assemble dry or with lithium grease H D says dry D Max warpage 006 E 78 1 2 late style rocker box Boss under front for ham can mounting and shortened boss on back left side using shorter stud F Rocker arms 2 types 1 front exhaust rear intake and front intake rear exhaust 2 case hardened max wear or pitting more than 005 replace pad or socket area 3 66 70 rocker arms were copper plated 66 arms 71 up iron arm with more even wear 66A arms will retro fit 82 up had a ground out 1 degree to offset for negative angle in the cover pad area 4 rocker arm end play a specs 004 025 Good is 004 010 b alter end play 1 best method cut a shoulder on the shaft 2 good method chamfer rocker arm spacer 5 8 3 4 countersink 90 degree angle 3 bad method shim the rocker arm do not do this 5 rocker shaft a 66A part number if o ring seat
84. What are the 2 parts of the float valve assembly e Float needle e Float needle seat What is the purpose of the spring loaded pin on the float needle e Acts as a shock absorber between the float needle and float tang What are the 2 most common methods of measuring the level of fuel in the float bowl e Measuring float level e Measuring fuel level A higher than normal float measurement will result in low fuel level and a lean air fuel mixture to all circuits 14 15 A lower than normal float measurement will result in a high fuel level and a rich air fuel mixture to all circuits Some carbs use a diaphragm instead of a float bowl Why e It can operate at any angle Friction Reducing Devices 10 11 What are some purposes of bearing and bushings Reduces friction Takes up shaft end play Proper spacing Support axial and radial loads What are axial thrust loads e Side to side loads What are radial loads e Rotational loads What is a journal e Area of shaft that turns on or is supported by a bearing or bushing Name 4 types of rolling element bearings e Ball bearing e Needle bearing e Roller bearing e Tapered roller bearing Which of these 4 bearings can handle radial loads but only thrust loads in one direction e Tapered roller bearings Which of these bearings can handle radial and axial loads in both directions e Ball bearings Which of the 2 anti friction bearings can only take
85. When starting the engine this system works best with the throttle open B Enrichener 1 Parallel with all other circuits 2 When on a passage way is open allowing fuel to flow through the circuit 3 Parts of the circuit a Enrichener fuel jet Normally located in the float bowl b Enrichener air bleed jet Located on the atmospheric side of the carburetor c Siphon tube Located in the float bowl d Starter plunger valve on off valve e Enrichener outlet port 1 Located la Mechanical slide carburetors e On the engine side of the slide NOVEMBER 23 1999 PAGE 2 1b Constant vacuum and fixed venturi carburetors e On the engine side of the throttle plate 4 When starting the engine this system works best if the throttle is closed C Tickler 1 A spring loaded rod that holds the float valve open when on 2 Itis not EPA approved Used mostly on older carburetors 3 Auxiliary circuits A Used to compensate for a lean condition B One or more may be found on any type of carburetor C Types of auxiliary circuits 1 Accelerator pump e SEE FIGURE 8 24 a Purpose To prevent temporary lean conditions during rapid throttle openings 2 Parts a Pump Actuated by the throttle linkage or slide inlet and outlet check valves b Discharge nozzle Located on the air filter side of the venturi c Operation 1 During rapid throttle openings the pump diaphram pressurizes the fuel in the pump body 2 Un atomized fuel is then forced thr
86. XILIARY CIRCUITS NOTES NOVEMBER 22 23 1999 THEORY NOTES SUBJECT Constant velocity carburetors e SEE FIGURES 8 18 and 8 19 KEY POINTS 1 Used on most modern street motorcycles A The carburetor delivers only the air fuel mixture that the engine can use so acceleration is very smooth B Compensates for changes in mixture that are caused by changes in altitude 2 Slide operation A Two types 1 Rubber diaphram 2 Metal piston B The slide moves due to pressure differences 1 Venturi pressure pressure above the piston due to the vacuum port in the bottom of the slide 2 Atmospheric pressure pressure pushing the slide up due to passage in the carburetor 3 When the difference in pressure between the atmosphere and the venturi is great enough to overcome the weight of the slide and the force of the spring the slide rises C Most CV slides have no cut away D The venturi is never less than 1 4 open E The throttle valve controls air flow up to throttle 3 Circuits A Idle circuit also called a slow speed or a pilot circuit 1 Main effect Idle to about throttle opening 2 Flows fuel 100 of the time overlaps all other circuits NOVEMBER 22 23 1999 PAGE 2 3 Parts a Idle air bleed passage Aids in atomization by mixing air with fuel b Air or fuel mixture screw usually fuel mixture screw Q Idle fuel jet meters the amount of fuel flow through the idle circuit d Idle outlet port 1 The only port
87. all gears not including hydraulic units 1 install with flat sides facing each other a failure to install properly will prevent the exhaust from pumping up 2 inspection 001 max tappet wear and 0015 max roller bearing clearance a inspect tappet screen every time you change oil open end down spring over screen J Hydraulic lifter 1 lifter test a dissassemble lifter unit bleed and clean with contact cleaner b with unit dry manually compress and hold for 6 seconds when released plunger should pop up 2 lifter problem causes a oil pressure need a minimum of 12 PSI at 2000 RPM b oil path restriction tappet screen blocked c tappet installed backwards d gasket misaligned at tappet guide 3 install tappet guide with installation tool in back use every time to align tappets with cam 4 similar noises often mistaken for lifter problems a excessive rocker arm end play b loose cam gear fit c exhaust leak d sticking valve e bent pushrod f worn tappet roller bearing K Cam Breather and Pinion Gear 1 cam endplay must be measured before cover is removed 2 breather gear endplay using a new gasket feeler gauge and a straight edge measure between straightedge and breather gear with the gasket in place than subtract 006 for gasket crush ideal endplay is 005 010 3 cam fitment see hand out page 2 15 a ideal straight no lash b loose fitment noise clatter c tight fi
88. alve closing 6 Factors that affect spring rate a Material used to make spring b Wire diameter 1 Thickness of the wire 2 Larger the diameter the higher the rate c Mean diameter 1 Centerline diameter of the spring 2 Increasing the mean diameter lowers the spring rate d Number of active coils Higher the number of active coils the lower the spring rate D Types of springs used for valve operation 1 Straight wound spring a l spring rate Has equal distance between active coils b Amount of force to compress it is proportional to distance it is compressed NOVEMBER 1 2 1999 PAGE 3 2 Multi rate wound spring a Two or more spring rates b Force required to compress it is not proportional c During beginning of compression the spring is soft d Towards the end of compression the spring is very stiff 3 Progressive wound valve spring Not common in stock motorcycles a Spring rate changes progressively b Has unequal distance between active coils c More expensive to manufacture than mult rate 4 Install progressive and multi rate wound springs so tight end remains stationary does not move 3 Valve closing devices Device used to close the valve A Two basic types e Coil springs most common SEE FIGURE 4 32 e Desmodromic Ducati only SEE FIGURE 4 33 1 Coil springs a Two springs Inner spring and outer spring per valve most common design b Considered to be in parallel c Reduces chance
89. alve moves off the seat measured in inches or millimeters C Valve duration Defined as the time in crankshaft degrees the valve is off the seat D Parts of cam 1 Base circle a Part of cam with constant radius from centerline of journal to heel forms base of the cam b Cam duration is the time that the valve is open c Distance from the top of the base circle to the nose helps determine maximum valve lift d Shim and bucket types Cam lift valve lift e Rocker arm types Cam lift X rocker arm ratio valve lift 2 Heel a The area of the cam that allows the valve to close b Allows time for valve to dissipate heat and whole valve train to recover 3 Clearance ramps acts similar to a shock absorber they gently open and close the valves 4 Flanks a Area of cam that determines acceleration of valve closing and opening b Opening flank can have a different profile than closing flank 5 Nose Area of the cam that determines duration of maximum valve lift a Determines cam lift 1 Distance the poppet valve is moved off of its seat measured in inches or millimeters E Cam manufacturing methods NOVEMBER 1 2 1999 PAGE 9 1 Cast a Molten metal is poured into a casting then machined to final shape b Cheapest method of production c Very good wear factor and oil retention d Disadvantage is that they are very brittle 2 Billet a Machined from a solid piece of round stock b More expensive to manufacture because of mac
90. and bounce front end B Hold front brake ignition on and bounce front end same amount there should be noticeable increase in spring tension WHEEL AND TIRE INSPECTION AND SERVICE 1 Tires wear replace tire if wear pattern is uneven wear bars are exposed or vehicle handles poorly A Damage inspection replace tire if sidewall shows damage such as cracks or puncture replace tire if tread area puncture is sideways to carcas or puncture size is greater than1 4 also inspect for correct mounting bead seated evenly and tire rotation 2 Service tire pressure should be set to factory specs and should not exceed maximum tech 2 Tech 2 listed on side wall 3 Wheels spin wheel to inspect for any damage or out of true A Feel for bearing end play 002 006 B Cast wheels if out of true or cracked replace 1 max runout radial 1 32 lateral 3 64 C Spoke wheels check spoke tightness each spoke should emit a high pitched ring when tapped all spokes should sound the same 1 max runout radial and latera 1 32 MISC LUBRICATION 1 Wheel bearing grease can p n 99855 89 cartridge p n 99856 92 A Except 80 81 FLT B Any taper bearing C Any part with a grease fitting 2 H D high temperature grease p n 99862 72 A Points cam 3 Anti seize some brake caliper pins axles front brake lever pins throttle sleaves 4 Triflo Lubit 8 Tufoil teflon lubricant p n 94968 85TB cables bracket and lever piv
91. and sometimes the intake port 4 Transfers heat away from the piston B Types 1 Cast iron boreable 2 Aluminum with cast iron sleeve boreable NOVEMBER 8 9 1999 PAGE 2 3 Plated aluminum cylinder not boreable and do not relieve the ports a Chrome b Electroplated C Cylinders should be true with no taper or out of roundness D Two stroke cylinders will have the most amount of wear in center because of the ports less surface area E Measuring cylinders for piston to cylinder clearance F Bridged ports 1 Used on very wide ports a Purpose To prevent ring snag b After boring cylinders the exhaust port bridge must be relieved c Upper and lower edges of all ports must be chamfered to help push piston ring back into groove 3 Pistons e SEE FIGURES 5 5 5 6 AND 5 7 A Purposes 1 Transfers power to the connecting rod 2 Aid in sealing the secondary area 3 Thrust and sealing surface for the piston rings 4 Control opening and closing of exhaust and transfer ports and sometimes the intake port B Manufacturing methods 1 Cast 2 Forged C Differences of two stroke pistons 1 Rings are pinned in place to prevent them from rotating which could cause ring snap NOVEMBER 8 9 1999 PAGE 3 2 Have no oil holes 3 Cylinder reed valve pistons have a cut away or windows on the intake side of the skirt 4 Have one to three rings all compression rings 5 Some have two or three small holes on exhaust side of piston
92. arcase cover a b c d Bolt torque patterns given in Tech Tips 25 2 dowel pins are for centering cover computerized sizes for gear fitment i quadrex room temp of 68 degrees ii measures center to center of bushings down to 0 00000 hundred thousandths iii prints sheet telling what cams to use iv production covers have no markings but information is on file at HD v P amp A covers are color coded for correct cam selection 1 PN 25488 86 cover with cams and pinion gear T cams 2 Cover only retrofits all alternator covers 84 1 2 Service of gearcase area i Replace cover order cover and cams as a set ii Replace bushings 1 Must line ream Cams a b 1986 1987 T cams i same cam in 883 and 1100 ii dogbone installed with the chamfer facing cam out 1988 1990 C cams i same cam used in 883 and 1200 ii reduced emissions iii dogbone installed with chamfer facing cam out flywheels a b c d e 3 piece flywheels i 1 piece flywheel halves ii no retrofit except left side wheel from pre comonized to comonized must rebalance oil restrictor in the pinion shaft no rear cylinder advance mark balance factors used to balance at speed higher balance at higher RPM lower lower RPM balance i 1340 60 ii 1100 69 blue iii 883 62 yellow iv 1200 62 white v after 1989 all 883 flywheels are colored green and all 120
93. as the B T Rocker arm play is 0 003 to 0 013 between rocker arm and rocker box endplay Bolts are hardened and CANNOT be replaced or mixed with unhardened bolts Rocker shaft to Rocker box clearance for all XL s is 0 0007 to 0 0022 ID to OD clearance 9 16ths 18 tap is used to push out rocker arm bushings from the opposite side then press in new bushings Pushrod tubes a 1986 1990 i multipiece tube ii both top and bottom seal against an o ring Cylinder Head a Early 883 egg shaped chamber and sand cast b Late 883 round hemispherical shaped chamber die cast c 1986 to early 1987 1100 egg shaped chamber sand cast d Late 1987 1100 and all 1200 round hemispherical shaped chamber die cast e Late 1100 heads were milled 0 040 i That milling did not continue on the 1200 Torque pattern gt gt gt Front cylinder 1 8 turn at a time Torque to 7ft lb then 14ft lb Rear cylinder Then turn 1 4 turn 90degrees 10 Early head bolts have large spacers later ones have a flange built onto the stud changed 90 91 a Lightly oil bolt after cleaning used as anti seize 11 Rocker arm bolts longer bolt is on the pushrod side 12 Valves a 883 has the smallest b 1100 from 1986 to early 1987 were the same as the B T 1340 valves c 1100 in late 1987 decreased diameter of valves i Late 87 1100 and all 1200 valves are the same size ii The change resulted in better mid range d
94. ase is pressurized 23 24 25 26 2T 28 29 30 31 32 What could be some possible symptoms of a wet side primary drive crankshaft seal leak e Engine will smoke excessively e Poor low end performance e Possibly fouled sparkplugs What could be some symptoms of a dry side ignition side crankshaft seal leak air leak e Engine will run lean e Engine will overheat which could lead to seizure e Wet on the timing side with oil not condensation What test is given if you suspect that a 2 stroke engine is no longer airtight e Pressure and Vacuum test What areas of the engine must be sealed before beginning the test e Intake and Exhaust What location should the piston be placed in before testing e BDC Test pressure should be between 6 and 9 PSI with no more than 1 PSI per minute leakage When vacuum testing place 9 inches of vacuum in the engine with no more than 1 inch of vacuum per minute leakage Besides the test adapters 6 possible area s of leakage that should be checked Intake manifold gasket Cylinder head or base gasket Timing side seal Primary side seal Center case gasket Test equipment What are 2 methods of lubricating a 2 stroke engine e Pre mix e Oil injection What is the formula for determining the proper amount of oil to mix with a pre determined amount of gasoline e 128 ratio gallons oz oil needed Which pre mix ration has more oil per gallon of ga
95. asteners 1 torque axle nut and replace cotter pin 2 snug axle adjuster screw and locknut 3 readjust brake on mechanical brake models 3 Rear chain R amp R Loosen rear axle nut and chain adjuster Bump wheel assembly towards the front Remove the old master link Attach the new chain with old master link Pull old chain to feed new chain on to sprockets Insure new chain is correct length 1 correct new length should put axle almost all the way forward 2 chain can be shortened 2 links at a time with a chain breaker Jawe THI oe S tech 2 Tech 2 a grind staked ends of pins off appropriate links with a grinder b use chain breaker to push pins out G Install new masterlink squeeze side plates over pins using vice grips and a small nut install safety clip so closed end points toward direction of travel BRAKE SYSTEM 1 Inspections A Master cylinder and linkage damage or leakage failure to return fully when released or sponginess when applying pressure B Perform a stationary test squeeze lever or depress pedal as hard as possible to make sure the system will not leak or fail make sure system releases and wheel turns freely C Check fluid for contamination and level any problem with master cylinder requires rebuilding or replacement fluid change level should be 1 8 from top with reservoir level D Linkage inspection damage wear non stock parts E Adjustment inspection freeplay must exist in most brake systems 1
96. ate free wheel on e Transmission driveshaft What is the purpose of a shock hub found on the back of some clutch baskets e Absorbs excess power reduces harshness in power change What plate is attached to and driven by the outer basket e Drive plates What plate is attached to the inner hub e Driven plates What is the inner hub splined or fastened to e Transmission drive shaft What applys spring pressure to the disk stack when the clutch is engaged e Pressure plate 13 14 15 16 17 18 19 20 2N 22 What 3 types of springs are most commonly used to squeeze the clutch plates together e Coil spring e Diaphragm e Tension What is the power flow through the clutch with the clutch engaged e Engine to outer basket to drive plates to driven plates to inner hub to transmission shaft What is the power flow through the clutch with the clutch disengaged e Engine to outer basket to drive plates Define clutch slippage e Clutch doesn t transfer 100 power What could cause clutch slippage e Improper adjustment or assembly e Weak clutch springs e Worn drive or driven plates Define clutch drag e Clutch doesn t fully disengage What could cause the clutch to drag e Warped metal plates e Worn outer basket or inner hub e Improper adjustment Name the 7 types of clutch release mechanisms Rocker arm Ball and ramp Rack and pinion Lever Cam Screw Hydraulic What type of
97. ath for oil flow f Late 1987 has a new valve rubber ball spring and new fitting i Ball to change in material and size m 950 1 Some sticking shut 2 Also redesign of adapter g 1992 production change ball was changed again has a tail PN 33116 86A iv oil back to pump through large hose v through pump and into engine case and gearcase cover vi first to lower end 1 restrictor on pinion shaft reduces oil flow to rods 2 increases oil flow to top end vil path through gearcase cover and case sends oil to tappet blocks lifters pushrods and rocker arms viii all other areas are splash and drip Iron heads 80 oil to bottom end 20 to top end Evo engines 20 oil to bottom end 80 to top end ix oil returns though cylinder drain holes and pushrod tubes 1 oil collects in mini sump 2 oil collects in gearcase cover and drains into mini sump x 3 things control oil return 1 spinning of flywheel and case scraper 2 downward action of the piston creating pressure in the case 3 suction of oil pump return gears PRIMARY DRIVE AND COVER 1 Clutch cable Tm O NAW PS sits below oil level Hylomar on threads copper washer under nut don t damage o ring part of cable no seperate part number some cables leak at crimped area replace 88 clutch cable 1 o ring at end 2 adjustable in middle of cable 3 88 primary cover changed for o ring 4 cable will retro fit to 86 2 Clutch adjustment
98. bustion Efficiency Percentage ratio comparing how much of the engines original air fuel mixture has completed the entire combustion process e Thermal Efficiency Percentage ratio comparing how much heat the engine produces to how much is used to produce power e Stroke Efficiency Percentage ratio comparing how far the piston travels under useful pressure to the total distance it travels e Mechanical Efficiency Percentage ratio comparing how much power is produced to how much is lost Give a brief description of e Stroke Piston travel from dead center to dead center top to bottom or vise versa e Top Dead Center TDC The point at which the piston is the furthest distance from the crankshaft e Bottom Dead Center BDC The point at which the piston is closest to the crank What do these abbreviation represent BTDC Before Top Dead Center BBDC Before Bottom Dead Center ATDC After Top Dead Center ABDC After Bottom Dead Center TDCC Top Dead Center Compression What are the 5 events in order of a 4 stroke engine Intake Compression Ignition Power Exhaust How many strokes does the piston make to complete these 5 events e 4 strokes How many revolutions does the crankshaft make to complete all 5 events e 2 revolutions How many revolutions does the camshaft make to complete all 5 events e revolution Why does timed ignition occur before TDC e To allow for combustion lag When and on what
99. cal shaped chamber die cast c 1986 to early 1987 1100 egg shaped chamber sand cast d Late 1987 1100 and all 1200 round hemispherical shaped chamber die cast e Late 1100 heads were milled 0 040 i That milling did not continue on the 1200 Torque pattern gt gt gt Front cylinder 1 8 turn at a time Torque to 7ft lb then 14ft Ib Rear cylinder Then turn 1 4 turn 90degrees 35 Early head bolts have large spacers later ones have a flange built onto the stud changed 90 91 a Lightly oil bolt after cleaning used as anti seize 36 Rocker arm bolts longer bolt is on the pushrod side 37 Valves a 883 has the smallest b 1100 from 1986 to early 1987 were the same as the B T 1340 valves c 1100 in late 1987 decreased diameter of valves i Late 87 1100 and all 1200 valves are the same size ii The change resulted in better mid range d XL s have longer valve stems than B T e There are no service values available 38 Cylinders a Different castings between the 3 different motors i 883 1100 and 1200 stamped into bottom right corner of cylinder ii cylinders are all the same length and use the same sleeve iii sleeve is just bored out more for the larger displacement 1 stock bore a 883 3 00 b 1100 3 35 c 1200 3 50 d 883 can be bored out to 1200 39 pistons 40 41 42 43 w wa wm ma a Karl Schmidt German b 1986 to early 1989 no offse
100. cavity 3 Builds 2 4psi activates sending unit and oil light turns off 4 Cold oil pressure high oil pressure 5 Pressure regulator bleeds off excess oil to gearcase opens at 16 18psi 6 Regulator left out or stuck open lifter collapse and oil pressure drop 7 Oil through filter to center of filter 8 Oil through check valve a Opens at 4 6psi b Check valve creates backpressure activates sending unit faster c Arrow on valve indicates direction of flow d Should point towards adapter with o ring to the outside counter bore e If installed backwards it will damage the o ring and create unfiltered path for oil flow Late 1987 has a new valve rubber ball spring and new fitting i Ball to change in material and size m 950 1 Some sticking shut 2 Also redesign of adapter g 1992 production change ball was changed again has a tail PN 33116 86A oil back to pump through large hose through pump and into engine case and gearcase cover first to lower end 1 restrictor on pinion shaft reduces oil flow to rods 2 increases oil flow to top end vii path through gearcase cover and case sends oil to tappet blocks lifters pushrods and rocker arms viii all other areas are splash and drip Iron heads 80 oil to bottom end 20 to top end Evo engines 20 oil to bottom end 80 to top end ix x oil returns though cylinder drain holes and pushrod tubes 1 oil collects in mini sump
101. clutch uses weights springs and engine RPM to engage and disengage power flow no clutch level e Centrifugal Why do some centrifugal clutches have a manual release mechanism built into them e To allow for engine breaking when off throttle 23 What is the purpose of the variable ration clutch e To always have the engine in the meat of the power band 24 What is a sprag clutch and where can it be used e Clutch that engages in one direction only used in starter motors and some high HP main clutches Constant Velocity Vacuum Carburetors 1 Why is the CV carb used on just about every street motorcycle today e It delivers only the air fuel that the engine can use and compensates slightly for changes in altitude 2 How is the slide movement controlled in a CV carb e Moved by pressure differences 3 What is the hand throttle controlling on a CV carb e The throttle plate 4 How does the low pressure air get to the top of the slide e Through a hole in the slide pressure passage 5 What is used in the CV carb to keep the vacuum and atmospheric pressure separated on the slide e Rubber diaphragm e Metal piston 6 Where is the idle outlet port located on CV and fixed venturi carbs e Engine side of the throttle plate Ta Where are the by pass ports located on CV and fixed venturi carbs e On the air filter side of the throttle plate 8 On variable venturi carbs the jet needle and needle jet are used to vary the m
102. clutches semi automatic clutches e SEE FIGURE 6 18 1 Has no clutch lever 2 Clutch engage is dependent on RPM 3 Uses drum weights springs and centrifugal force 4 When engine RPM is high enough a Centrifugal force forces the weights outward b Friction material contacts the inside of the drum to engage 5 Some use a manual multi plate clutch along with a centrifugal clutch 6 Manual type clutch has a clutch release linkage attached to the gear shift linkage NOVEMBER 10 12 1999 PAGE 7 7 When arider shifts gears the linkage disengages the manual clutch allowing the transmission to shift gears C Variable ratio clutches e SEE FIGURE 6 10 1 A clutch and a transmission combined 2 Consists of a V belt primary sheave pulley and a secondary sheave pulley 3 Primary and secondary sheave contains a fixed sheave half sheave weights springs and a cam sliding sheave half 4 Atrest or idle speeds the V belt is located a At the center of the primary sheave b At the outer perimeter of the secondary sheave 5 As engine RPM increases the sheave weights are thrown outward by centrifugal force This causes a The primary sliding sheave to move inward b The secondary sliding sheave to move outward c V belt is forced toward the outer perimeter of the primary sheave and the inner diameter of the secondary sheave D Sprag clutches also known as a slipper clutch 1 A clutch that engages in one direction only 2 Found i
103. ctor gear 4 Gear identification A Spur gear 1 Has straight cut teeth 2 Most common gear 3 Noisy 4 Inexpensive to manufacture 5 Entire tooth meshes at once 6 Does not create side loads B Off set spur gears 1 Two spur gears side by side 2 Teeth are offset by 1 2 a tooth 3 Purpose To reduce gear backlash Play between the teeth of two meshed gears C Helical gears 1 Has angle cut teeth 2 Entire tooth does not contact at once 3 Quieter than spur gears 4 Create thrust side loads D Internal gears 1 Very strong and compact 2 Gives very high gear reduction ratio 3 Most commonly used in electric starter motors and shift linkages NOVEMBER 9 10 1999 PAGE 3 E Worm gears 1 Gives a high gear reduction ratio 2 Used with a spur gear 3 Will normally be a drive gear 4 Most commonly used in speedometer and tachometer drives F Idler gears 1 Used to correct the direction of rotation 2 Will not change gear ratios 3 Can have any tooth configuration G Bevel gears 1 Used to transmit power at 90 degree angles 2 May have either of two patterns a Spur bevel straight cut teeth b Spiral bevel Curved teeth has greater engagement 3 Most common design for pinion gear DRIVE on final shaft drive systems H Ring gears 1 Metal wheel gear with teeth around its inner edge 2 Most common design for final driven gear for shaft drive systems 3 Used with pinion gear I Sector gears
104. d a b Same as alternator iron XL engine i Plastic baffle ii Umbrella valve Small hole under the valve to relieve oil buildup at breather i Hole must be open or air cleaner will get oil Oil pump 4 speed a b c d e f g Operation is the same as 77 pump Feed gear height 0 001 0 011 above pump cover Feed gears were enlarged to supply lifters i Return gears are still larger than feed Gear clearance inner and outer gear i Wear limit 0 004 ii Use shaft to center gears in body Seal lip numbers side toward feed side Oil pressure i Measure at the top plug in the case or the sending unit on the filter housing 1 Factory specs 1 7psi at idle and 5 30psi at 2500 rpm 2 If taken at the sending unit readings will be double Oil flow i Flows from oil tank to the pump cover ii iii iv v vi Feed gear pressurizes oil through small hose to housing 1 Special hoses 2 different fitting sizes no sealant needed Oil filter adapter housing 1 Pressurized oil to adapter housing 2 Enters adapter through drilled holes and fills cavity 3 Builds 2 4psi activates sending unit and oil light turns off 4 Cold oil pressure high oil pressure 5 Pressure regulator bleeds off excess oil to gearcase opens at 16 18psi 6 Regulator left out or stuck open lifter collapse and oil pressure drop 7 Oil through filter to center of filter 8 Oil through check valve a
105. e Spark engine What does the C in the API rating stand for e Compression engine diesel The API classifications met the manufactures minimum requirements for what years e SC 64 67 e SD 68 71 e SE 72 79 e SF 80 89 e SG 90 93 e SH 94 present What is the difference in the wet sump and dry sump lubrication systems e Wet Sump uses one pump to force oil into the engine gravity feeds back to the oil pool e Dry sump uses 2 pumps one to force oil into the engine one to return the oil to a holding tank Why are there 2 pumps in a dry sump system e One to pump the oil into the engine e One to pump the oil out of the cases and into the oil tank What is the purpose of the oil pump e To force oil through the engine 21 22 23 24 25 26 27 Name 3 types of oil pumps used in motorcycles e Tricohoidal e Gear e Pump What is the purpose of the oil pressure relief valve e Prevents excessive oil pressure What is the purpose of the oil filter by pass valve e To allow continued oil flow when the filter is clogged What is the purpose of the oil filter e To clean the oil Name 4 types of oil filters used in motorcycles e Paper e Fiber e Mesh screen e Centrifugal What is the purpose of using grease for lubrication e To lubricate where oil cannot be contained What is the purpose of using a dry lubricant on a motorcycle e To lubricate witho
106. e area 2 Location a Piston port or cylinder reed engines 1 Lowest port on the cylinder wall 2 Piston port opening closing is controlled by the position of the piston skirt 3 Cylinder reed opening closing is controlled by induction systems covered later b Rotary valve or crankcase reed e SEE FIGURES 5 15 5 16 AND 5 17 1 Crankcase 2 Opening closing controlled by induction systems covered later B Transfer port NOVEMBER 5 8 1999 PAGE 2 1 Purpose control transfer of the fresh charge from the primary area to the secondary area 2 Location middle port on the cylinder 3 Opening closing controlled by the position of the piston crown C Exhaust port 1 Purpose control the flow of the spent charge into the exhaust system 2 Location highest port on the cylinder wall 3 Opening closing controlled by the position of the piston crown 4 Six events of a two stroke engine A To complete all six events it takes 1 Two strokes of the piston 2 One revolution of the crankshaft B Six events e Intake event into primary area SEE FIGURE 5 23 e Compression event into secondary area SEE FIGURE 5 24 e Timed ignition e Power event SEE FIGURE 5 25 e Exhaust event SEE FIGURE 5 26 e Transfer event SEE FIGURE 5 22 1 Intake event a Starts with piston moving towards TDC NOVEMBER 5 8 1999 PAGE 3 b Primary area is increasing and pressure is decreasing c Because of the pressur
107. e clean of rust and dirt 5 Must have a float arm float to operate the fuel gauge B Fuel valves also called petcocks e SEE FIGURE 8 2 1 On off valves for fuel delivery from the fuel tank to the carburetor 2 Located on the fuel tank carburetor or anywhere between the carburetor and the fuel tank 3 Four common types a Manual has a lever with three positions ON RES reserve and OFF b Vacuum has a lever with three positions ON RES reserve and PRI prime e SEE FIGURE 8 3 NOVEMBER 19 1999 PAGE 2 1 Fuel flow la ON and RES position Flows only when engine vacuum is present at the fuel valve lb PRI position Fuel flows at all times lc Normally has two hoses one for fuel delivery and another for engine vacuum c Electric The fuel valve is actuated when the ignition switch is turned to the ON position d Vacuum with electric assist 1 The fuel valve is normally actuated by the engine vacuum 2 When fuel in the fuel tank is low it is electrically switched to the reserve setting C Throttle controls 1 Allows the rider to control the carburetor throttle opening and engine speeds 2 One cable or two cables 3 Free play must be adjusted periodically D Fuel lines 1 Usually neoprene Must not be adversely affected by fuel 2 Routing a Route the fuel line away from hot engine parts and carburetor linkage b Route the fuel lines with no kinks E Fuel pumps 1 Purpose Delivers fuel from the
108. e differences fresh air fuel oil mixture is pushed into the primary area 2 Compression event Secondary compression volume compressed above the piston by the piston movement towards TDC 3 Timed Ignition event occurs just before TDC to allow for combustion lag 4 Power event a Starts ATDC when combustion forces the piston down and ends when exhaust port opens b Hot expanding nitrogen gasses force the piston downward 5 Exhaust event a Starts when the piston crown opens the exhaust port while moving down towards BDC b Pressures on top of the piston are no longer useful to make power c Because of pressure differences the spent charge is pushed into the exhaust system d Low pressures in the exhaust system e Higher pressure in the secondary area 6 Transfer event a Piston starts BBDC and travels towards BDC b Primary area is decreasing pressures are increasing primary compression c Secondary area is increasing pressures are decreasing d Because of the pressure differences between the primary and secondary area the fresh charge is pushed through the transfer ports to secondary area e Transfer occurs during the exhaust event this helps scavenge residual exhaust gasses f Transfer event has the shortest port duration 5 Scavenging similar to four stroke valve overlap A Occurs when the exhaust and transfer ports are open at the same time NOVEMBER 5 8 1999 PAGE 4 B Purposes 1 Scavenge residual
109. e force of energy What is said to be connected at the ends of the magnet e Flux lines What are the ends of a magnet called e Poles Flux lines are said to travel from the north pole to the south pole Like poles will repel one another Unlike poles will attract one another Name 2 types of magnets that can be used on motorcycles e Permanent magnet e Electromagnet What is a disadvantage of a natural magnet e Very weak What type of magnet is man made of metal alloys to be lightweight but have a strong magnetic field e Permanent magnet What type of magnet can have the strength of the magnetic field varied or even turned on or off e Electromagnet What is permeability e Ease in which the flux lines pass through something What is residual magnetism e When a permeable substance doesn t lose all it s magnetism eventually becomes a permanent magnet What are the purposes of a soft iron core e Concentrate flux lines e Retain residual magnetism 14 15 16 17 18 19 20 21 22 23 24 25 What are 2 purposes of a laminated iron core e Concentrate flux lines e Doesn t retain residual magnetism What principal causes and ignition coil to operate e Mutual induction Give a brief description of the primary coil winding in the ignition coil e Low voltage wire with a few hundred turns creates the magnetism Give a brief description of the secondary coil winding in the ignition c
110. ed 1 turn to position clutch arm 13 16 from transmission top 2 tighten locknut g adjust cable to provide 1 8 to 3 16 cable freeplay between cable end and lever bracket F diaphragm spring installs convex out G adjuster plate provides three positions for spring attitude adjustment H pressure plate release plate is held in with a tapered snap ring installs with taper out I updates 1 mid92 parts and accesories change adjuster plate no longer provides 3 positions for spring adjustment suggest to use shims if necessary to space outward 13 Clutch plates A 6 driven plates 1 friction materials a STD 84 1 2 to 8 4 86 no asbestos heavy use could ruin b screaming eagle type 8 5 86 to 5 12 88 paper construction much better friction c sintered bronze type 5 13 88 to 89 production almost indestructable some slippage with heavy use 2 service minimum thickness 078 max warpage 011 3 never wipe with rags or dip in solvent 4 always oil new plates before installation B 7 driven plates steels 1 84A plates may not fit over 84 hub 2 service minimum thickness 044 max warpage 011 install with rounded side out all plates should slide freely over the hub 14 Clutch shell A ring gear and sprocket are shrink fit same slippage of ring gear noted on early productions B do not pry on shell fingers breakage 15 Clutch hub A pressed into hub bearing which is pressed int
111. eeth on pinion What type of gear is used when shafts are at 90degree s to one another e Bevel What is an advantage of a spur gear e Inexpensive and no side loads What is an advantage of a helical gear over a spur gear e Quieter and stronger than spur gears What is the purpose of an idler gear e To change the direction of rotation Name 3 types of gears that can be used in primary drives e Spur e Offset spur e Helical What type of belt is used in primary drives e Gilmer belt toothed Name 4 types of chains that can be found in primary drives e Single row e Double row e Triple row e Hi vo Some motorcycles use a primary shaft in the primary drive What can it be used for e Drive the clutch change direction of rotation or operate a charging system GENERAL 66 69 generator bottom end 70 84 AC generator cone motor magnet spins around windings Installation of engine right side A rock motor corner to corner to check fit B torque down rear motor mount C check front mount and frame for clearance shim any clearance than torque front mount D inspect clearance between top mount and frame shim for 0 clearance than torque Engine and tranny proceedure A install engine B loosely bolt primary to engine C with tranny and plate loose bolt primary to tranny D shim primary than torque engine and primary than torque tranny and primary E torque tranny and plate
112. ershaft A Ist gear smallest diameter gear 1 needle bearings B Countershaft 2nd and 3rd gears 1 same ratio since 1957 2 M 906 gear diameter reduced running 1986 a must be used on 1100 b early or late style ok on 883 Countershaft 4th gear 1 step towards door thrust washer 2 1987 ratio change a E 27T b L 26T grove on face of gear 3 flip KM transmission plate over a measure from end of splines to slider b use chart in manual to determine washer size End play 1 mainshaft 006 020 no preload 2 countershaft 004 015 use spoke to pull on shaft 3 proceedure a install without washers b measure end play and write it down c use charts in manual to determine washer size d reassemble and double check door bolt torque 14 ft lbs Harley Davidson Tech 1 1 Intro Dates a 883 started in early 1986 to present b 1100 started in late 1986 to late 1987 c 1200 started in early 1988 to present Case breather sportsters from 1986 1990 Iron sportsters from 1957 1985 2 3 4 5 6 7 8 9 Compression Ratio a 9 1 on ALL models Rocker covers a Big Twins B T and Sportsters XL can be interchanged as a set i Topend breather covers must be used on top end breather motors ii Print o seal gasket and inner cork or rubber chimney are the same for B T and XL iii All rubber gaskets from late 1989 till current iv XLrocker arms and shafts are the same
113. exhaust gasses 2 helps cool secondary area C Methods 1 Cross scavenging a b c d Used primarily in marine engines Transfer port is located directly across from the exhaust port A large deflector is cast into the crown of the piston Deflector directs the air flow up and away from the exhaust port 2 Loop scavenging e SEE FIGURE 5 27 Transfer ports are located 90 degrees from the exhaust port Transfer ports are angled away from the exhaust port The angle of the transfer ports direct the fresh charge up and away from the exhaust port Fresh charge loops inside the secondary area helps scavenge residual exhaust gasses with minimum intake charge loss 6 Two stroke expansion chambers exhaust systems 7 SEE FIGURE 5 18 AND FIGURE 5 19 A Tuned chamber that operates off of sonic sound waves created by the engine B Aids in 1 Scavenging residual exhaust gasses 2 Transfer event 3 Reducing charge loss 4 Adjusting the power band characteristics of an engine NOVEMBER 5 8 1999 PAGE 5 Overview of port timing SEE FIGURE 5 3 AND 5 4 A Intake port piston port engines only 1 Usually open BTDC 2 Usually closes ATDC B Exhaust port 1 Usually opens BBDC 2 Usually closes ABDC C Transfer port Port with shortest port duration 1 Opens BBDC after exhaust port opens 2 Closes ABDC before exhaust port closes D Symmetrical port timing 1 Port opens and closes on
114. f air bleed passage e To enrichen the air fuel mixture turn clockwise in e To lean the air fuel mixture turn counter clockwise out e FUEL MIXTURE SCREW e Located on the engine side of the carburetor e Varies the flow rate of the idle outlet port e To enrichen the air fuel mixture turn counter clockwise out e To lean the air fuel mixture turn clockwise in 3 Idle fuel jet a Meters the amount of fuel flow through the idle circuits b Usually made of brass and can be a screw or press in c Jet number 1 The larger number indicates the larger jet 2 Indicates flow rating or the diameter of the orifice 4 Idle outlet port a The only port that flows fuel at an idle b Flows fuel 100 of the time overlaps all circuits c Located on the engine side of the slide 5 By pass ports also called transfer ports NOVEMBER 22 1999 PAGE 3 a Purpose Aids in smooth transitions by allowing a little more fuel flow just off idle b Located under the slide 6 The slide controls the size of the venturi a Controlled by a rider using the throttle twist grip b Shapes 1 Round 2 Flat 3 Radial flat half round and half flat c Side cut away found on most mechanical slides 1 Larger the cutaway The leaner the air fuel mixture 1 8 to 1 4 throttle opening 2 Purpose Aids in transition from the idle circuit to the mid range circuit 3 Cut away faces the air filter side of the venturi 4 Example
115. f iron core i solid iron core a concentrates flux lines b retains residual magnetism ii laminated iron core a made of thin sheets of iron riveted together b concentrates flux lines c doesn t retain residual magnetism never becomes a permanent magnet D Ignition Coils 1 Rapidly switching Electro magnet 2 Operates on the principal of mutual induction a mutual induction 2 conductors 1 flowing current magnetically induces current into 2 coil b no electrical connection between the conductors necessary 3 Ignition coils also use turn coil ratio to greatly increase voltage 4 Parts of an ignition coil a Primary coil windings i low voltage side converts input current into magnetism ii has a few hundred turns of wire b secondary coil windings i high voltage side converts magnetism into voltage ii has many thousands turns of wire 5 2 types of ignition coils a determined by which direction field move inwards or outwards 1 collapsing field a spark plug fires when the current to the primary coil is turned off b collapsing decaying field crosses secondary coil inducing high voltage at the plug 2 Rising field a plug fires when current to the primary is turned on b rising building field crosses secondary coil inducing high voltage at the plug E Electromagnet switches aka relays solenoids 1 Purpose a handle high current instead of a switch b energize or de energize an electrical circui
116. feet work done is 625 foot pounds 25lbs X 25 ft 625 ft lbs 2 Example 2 Ifa5 pounds weight is lifted off the ground 1 foot the work done on the weight is foot pounds 1 foot x 5 pounds 9 Power Rate at which work is done A Formula Power work divided by time interval during which the work is done B High powered machines do a large amount of work in a short period of time 10 Torque Twisting or Rotational force textbook page 26 27 A Formula Torque Force X Distance from the pivot point usually measured in foot pounds B May or may not result in motion C Examples 1 Force applied to torque wrench 2 Engine develops or produces torque to turn rear wheel wheel may not move but the force is there D Torque makes work and work makes power OCTOBER 27 1999 PAGE 11 Horse power Measurement of a force moving an object a certain distance and in a certain time A Formula Force X Distance moved per time unit horsepower in foot pounds per time unit compared to amount of power a specific horse had B Horse power is rated in work time units such as foot pounds second or foot pounds minute C For motorcycles horse power is a direct result of torque and RPM D Examples 1 1 horse power per second 550 pounds moved one foot in one second 2 1 horse power per minute more commonly used 33 000 pounds moved 1 foot in 1 minute Engine s horse power ratings indicate how much work
117. fuel tank to the carburetor or the fuel injector 2 Two common applications a The fuel tank is lower than the carburetor b Fuel injection systems 3 Supplies fuel under pressure see the service manual for specifications 4 Three types a Mechanical Uses a cam lever Diaphram and two check valves NOVEMBER 19 1999 PAGE 3 b Vacuum Diaphragm movement is controlled by the pressure differences of engine vacuum and atmospheric pressure c Electric An electric motor or electric solenoid relay drives the pump F Vent hoses of the fuel tank and the carburetor 1 If the fuel tank or the carburetor is not vented the fuel may not flow correctly 2 Service Check to make sure that the vents are not plugged kinked or routed incorrectly G Fuel filters 1 Purpose To remove contaminants from the fuel 2 Common locations a On top of the petcock in the fuel tank b In the fuel valve c In line of the fuel hose d On top of the seat in the carburetor H Air filter and housing 1 Purpose To filter the incoming air 2 Types of filters a Paper e SEE FIGURE 8 4 1 Uses treated pleated paper 2 Must be kept dry and free of oil 3 When dirty replace it Do not try to clean b Foam e SEE FIGURE 8 5 1 Foam is used to trap oil that traps dirt 2 When dirty clean in warm soapy water rinse and dry NOVEMBER 19 1999 PAGE 4 3 Oil the air filter with oil made for foam c Gauze 1 Surgical gauze is used to trap oil
118. g collar collar now rests on head surface instead of valve guide shoulder 3 L81 a cst iron guides longer with shoulder b ream or hone for proper clearance intake 0015 exhaust 0025 c valve guide seals umbrella type seals NOTE do not use loctite on a valve guide seal D Valves 1 hard valves Eaton hard chrome US made Nittan black nitride coating Japan made 2 stem diameter 80 valve diameter same as earlier models 81 valve is approximately 003 larger stem OD 3 80 and 81 valves are recommended for use with all cast iron guides 4 medium hard valves 57A and 66 valves are compatible with cast iron guides but not recommended due to short service life 5 soft valves 57 60 valves never use soft valves with cast iron guides causes valve sticking E Springs and hardware 1 spring ID silver 82 and earlier red orange L82 84 prevents coil bind with S cam 2 top retainer mid 81 and earlier thicker L81 and up 050 thinner for seal clearance 3 bottom collar 79 and earlier 9 16 ID sits on guide shoulder L81 and up 3 4 ID fits over seal sits on head surface F Cylinders cast iron all years 1200cc 3 7 16 bore 1340cc 3 1 2 bore 1 66 78 1200cc 10 fins with a thin base available untill 80 as an option 2 78 1 2 and up 1340cc 9 fins with a thick base 1200cc option a base is cut out for triangle washers round side faces down
119. haft 3 Anytime the inner hub is rotating the transmission main shaft is rotating 4 Most inner hubs supply the spring mounts for the clutch springs e Pressure plate NOVEMBER 10 12 1999 PAGE 4 1 When the clutch is engaged the clutch springs and pressure plate press the drive and driven plate together 2 When the drive and driven plates are pressed together the plates form one unit and allow power to flow through them 3 Pressure plates fit over the inner hub 4 When the clutch is disengaged the clutch release mechanism forces the pressure plate away from the inner hub This separates the drive and driven plates 5 Clutch springs a b Applies spring tension to the pressure plate Three types 1 Coil spring Most common spring free length specification normally in service manual 2 Diaphram springs Looks like a large convex washer Applies pressure 360 degrees 3 Tension springs Made from coiled wire but they are not compressed they are stretched They will have hooks at one or both ends 6 Power flow with the clutch engaged clutch lever released a b e Engine drives the outer clutch basket Outer clutch basket turns the drive plates Drive plates turn the driven plates Driven plates turn the inner hub Inner hub turns the transmission main shaft 7 Power flow with the clutch disengaged clutch lever pulled Engine drives the clutch outer basket Outer clutch basket turns
120. harge between 2 points What is the definition of a conductor e Material that allows free movement of electrons What are some examples of materials that make good conductors Gold Silver Copper Aluminum Steel What is the definition of an insulator e Material that doesn t allow electron movement 12 13 14 15 16 17 18 19 20 21 22 23 What are some examples of materials that are used as insulators e Rubber e Plastic e Air What is the definition of a semi conductor e A manmade product that can be either a conductor or an insulator What are 3 materials that are used in the manufacturing of semiconductors e Silicone e Germanium e Selenium What is electrical current e The rate of flow of current electricity What is the unit of measurement of current e Amps Direct Current DC can be defined as e Flow in only one direction Alternating current AC can be defined as e Alternating flow in both directions What method is used to produce AC e Induction What are 3 requirements necessary for induction to take place e Magnetic field e Conductor e Motion What is polarity e Direction of current flow The conventional flow theory states that electrons flow from the positive to the negative The electron current theory states that electrons flow from the negative to the positive HW Magnetism 10 11 12 13 What is magnetism e An invisibl
121. he drive train END OF PRIMARY DRIVE NOTES PAGE 2 NOVEMBER 23 1999 THEORY NOTES SUBJECT Three jet carburetion variation e SEE FIGURE 8 20 KEY POINTS 1 Variable venturi carburetor variation three jet carburetor not common A Allows for a better atomization of fuel in the mid range B Has arider controlled throttle plate both mechanical and constant velocity 2 Idle circuits Same as two jet carburetors 3 Mid range circuit A Primary main jet added 1 Main effect 1 4 to throttle opening 2 Purpose Gives a smoother transition in this throttle range and helps lower emissions 3 Primary main jet circuit consists of a Primary main fuel jet b Primary air bleed passage and jet c Discharge nozzle located between the transfer ports and the needle jet jet needle B Needle jet jet needle circuit works similar to two jet carburetors 2 to 34 throttle 4 Main jet circuit similar to two jet carburetors A Main effect to full throttle openings B Consists of 1 Secondary main jet fuel 2 Needle jet and jet needle jet needle taper starts about 2 throttle 3 Secondary main air bleed and jet END OF THREE JET CARBURETION VARIATION NOVEMBER 15 16 1999 THEORY NOTES SUBJECT Transmissions KEY POINTS 1 Purposes A To change the speed of the motorcycle B To keep the engine within its usable power band 2 Transmission design A Constant mesh transmission Teeth of all gears mesh with their mate
122. hine time c Much stronger than cast d Oil retention is not as good as cast F Camshaft drives 1 Types e Chain e Gear e Belt a Chain types 1 Single Roller Consists of la Plates lb Pins lc Bushings 1d Rollers 2 Duplex Roller two rollers per pin 3 Hy vo plate type la Consists of pin and plate NOVEMBER 1 2 1999 PAGE 10 lb Very strong but requires horsepower to drive it lc Normally operates in oil bath b Gear 1 Most manufacturers spur gears 2 Sometimes bevel gears are used 3 Operates in an oil bath c Gilmer belt 1 Toothed belt 2 Used pulleys with teeth 3 Very quiet 4 Requires no lubrication 5 Alignment and tension are very important G Chain or belt tensioners 1 Purpose Keep proper tension on the chain or belt 2 Types a Manual Must manually adjust the tension by feel A lock nut holds it in place b Semi Automatic Loosen lock nut then spring tension tightens the tensioner c Fully Automatic Automatically adjusts as engine is operating H Types of valve trains 1 Push rod and rocker arm 2 Single overhead cam with rocker arms SEE FIGURE 4 22 b 3 Dual overhead cam with rocker arms SEE FIGURE 4 22 c 4 Dual overhead cam with shim and bucket SEE FIGURE 4 22 a END OF VALVE OPEN CLOSING DEVICES NOTES NOVEMBER 19 1999 THEORY NOTES SUBJECT Venturi effect and design KEY POINTS 1 Venturi effect based on Bernoulli s law A A law
123. how e 1 watt 1 volt pushing 1 amp in 1 second 4 What are the 3 basic Watt s Law formulas e Watts amps volts e Watts volts amps e Volts amps watts 5 What is the resistance of a 6V 45W headlight bulb e 45 6 7 5 6 7 5 8ohms 6 What is the wattage of a 12v 10ohm load service e 12 10 1 2 1 2 12 14 4watts 7 What is the resistance of a 35watt 8amp light bulb e 35 8 42 75 43 75 8 54 688 ohms 8 A 12y parallel circuit has 2 loads What is the current flow through the 2 load if the 1 load is 35ohms and the 2 is 10ohms e 12 10 1 2amps HW Electrical Terminology 10 11 An atom can be defined as e The smallest part of whole matter What are 3 basic parts of an atom and their type of charge and their location in the atom e Electron negative charge shell e Neutron neutral nucleus e Proton positive charge nucleus What special properties does the valence electron have e Outer most shell can gain or lose valence electrons Electricity can best be described as e The flow of electrons through a conductor Electromotive Force EMF can be defined as e The Force that induces valence electrons to move NOT the movement itself electrical pressure EME can be created by e Heat e Friction e Chemicals e Magnetism What is the unit of measurement for EMF e Volts What is the definition of Potential Difference e Imbalance of electrical c
124. i Early 1986 were loose rollers with flat thrust washers ii Late 1986 through current use F A G bearings started on day 095 d For the first 2 months no thrust washers were used added late May i Stepped for clearance wider cage e Service just like the B T bearings i 1 bearing size 3 sizes of crank pin Sprocket Shaft a 5 speed shaft is 0 750 longer than 4 speed i Rotor and stator moved to sprocket shaft from clutch shell ii Rotor pressed and screwed to socket 48 Pinion shaft and race 49 50 Na m a b c 1986 only unitized caged bearing pressed into case i Race pressed onto shaft 1 185 1 195 from flywheel race ii Grind to size 1 2485 1 249 16rms finish 1987 current uses F A G bearing i 3 pieces 1 outer race pressed into case 2 inner race pressed onto shaft 3 separate bearings ii 4 sizes of bearing iii races press to different depths see service manual 1988 to current pinion shaft i Pinion shaft is straight no splines ii Pinion gear is light press fit and keyed to shaft 1 Reduces gear runout better cam fit iii New pinion gear iv Nut has NO locktab so use locktite and torque to specs Breather system 4 speed a b Same as alternator iron XL engine i Plastic baffle ii Umbrella valve Small hole under the valve to relieve oil buildup at breather i Hole must be open or air cleaner will get oil Oil pump 4 speed a b c d e
125. idrange flow of fuel 9 The midrange circuit in variable venturi carbs will share an air bleed passage with the main jet circuit which is used to atomize the fuel Cooling Systems 1 What is the purpose of the cooling system e Rid engine of excessive heat e Allow the engine to operate in a specific temperature range 2 What are 3 types of motorcycle cooling systems e Internal e Air e Liquid 3 What would an advantage be of forced draft air cooled over open draft e Cooling even when stopped 4 Explain the purpose of these components in a liquid cooled engine e Water pump circulate the coolant e Inspection hole inspect water pump seal e Thermostat allows for quicker warm up and operation at a specific temperature e Radiator heat exchanger e Radiator cap seals the system and determines system pressure e Radiator fan draws air through the radiator 5 Why is distilled water used in cooling systems rather than tap water e Doesn t have any mineral deposits 6 What type of coolant anti freeze is used in most cooling systems and what is it s purpose e Ethylene or Propylene glycol and it lowers the freezing point of water as well as raises the boiling point we What is the normal ration of coolant to distilled water e 50 50 Electrical Currents 1 Circuits A Complete path for current to flow B From source and back through the path of least resistance a circle 2 Four requirements for a functioning circu
126. ine e Equalization of a low pressure area created in the cylinder 20 21 22 23 24 25 26 27 28 29 30 What is Matter e Material Substance that occupies space and has weight What are the 3 forms states of Matter e Solid e Liquid e Gas What is a definition of energy e The ability to do work Can matter or energy be created or destroyed e No Can Matter and Energy be changed from one form to another e Yes What is Potential Energy e Stored energy that can be released slowly or all at once What is the definition of Velocity e The speed of an object Define Momentum e The driving force of a moving object What is the definition of the Law of Inertia e Anything at rest or in motion will remain at rest or in motion until acted upon by an outside force What is the definition of Power e The rate at which work is done What is the definition of work e The useful movement of an object What is the definition of Horsepower e The measurement of force moving an object a certain distance in a certain time What is the definition of Torque e A twisting or Rotational force Two types of combustion engines are e Internal combustion e External combustion What is the scientific term for Combustion e Rapid combining of oxygen with other substances How does Heat affect a chemical reaction e Acts as a catalyst and generally hastens the reaction 31 32
127. ing the timed ignition occur after later than some given point usually the manufacturers specified timing at idle 4 Power event a Begins after ignition when expanding nitrogen gases force the piston towards BDC b Piston is only under usable pressure about 1 2 to 2 3 of the stroke of the piston c Exhaust valve timing RPM and length of stroke determine this d Linear motion of the piston being forced down produces rotary movement of the crankshaft e SEE FIGURE 4 4 5 Exhaust event a Exhaust valve opens BBDC during power stroke allowing the spent charge to escape due to pressures differences OCTOBER 28 29 1999 PAGE 4 b The piston passes BDC and travels toward TDC c Cylinder volume is decreasing removing residual exhaust gasses out of the cylinder d Intake valve opens BTDC allowing the fresh charge to enter the cylinder This also aids in scavenging residual exhaust gasses and cooling the combustion chamber e Scavenging is the removing of exhaust gases from the cylinder f Exhaust valve closes ATDC during the intake stroke e SEE FIGURE 4 5 3 Overview of valve timing NOTE The camshaft must be correctly timed to the crankshaft to prevent the intake and or exhaust valve s from contacting the piston A Intake Valve 1 Opens BTDC during exhaust event at the end of the exhaust stroke 2 Closes ABDC during compression event at beginning of compression stroke B Exhaust Valve 1 Opens BBDC during timed ignition
128. it A Source or EMF voltage 1 Battery or 2 Charging system or 3 AC source coil B Complete Path 1 Path for current to flow from source to load and from load back to source 2 Wire or motorcycle frame C Load device 1 Device the converts electrical energy to some other form of energy a light b horn c coil of wire heating element or Electro magnet 2 All load devices have some resistance D Means of control 1 Device that controls or limits total current flow 2 Switch 3 Circuit Protection A Fuses and circuit breakers 1 Fuses and circuit breakers are circuit protection devices 2 Excessive current flow causes excessive heat which result in blown fuses and tripped circuit breakers 4 Circuit types A Series circuit only one path for current to flow B Parallel circuit more than one current path C Series parallel circuit 1 Circuit with a series section through which current must flow before branching out into the legs of a parallel circuit 2 Example A charging system is a series parallel circuit with the battery in series 5 Unwanted circuit conditions A Open circuit 1 Incomplete path for the current to flow no continuity 2 Symptoms components will not work 3 Examples broken wire blown fuse open switch B Grounded Circuit unwanted 1 Circuit that has developed a path for current to flow back to its source After the load device but before the means of control 2 Symptom loss of means of con
129. kness washers used to adjust spacing of gears on countershaft C Use go no go method of spacing in hand out Cam follower detent problems M 949 A L84 E87 Steel zinc B M87 L87 aluminum C L87 90 aluminum w counter bore Mainshaft A Ist gear largest dia gear 1 M 934 recall 061 a 87 28T gear some break switched back to 52A gear 27T 2 Radius on all Ist gears to case for lubrication a press off on with the bearing races mainshaft 2nd and 3rd gears 1 same ratio since 57 2 3rd gear end play reduced by thicker washer running change 1986 a will retro fit to 1957 3 M 906 late gears smaller diameter a must be used on all 1100 s b early or late model ok on 883 c prevents root contact caused by 1100 shaft flexing d OK to mix early or late style on all xl models except 1100 or 1200 mainshaft 4th gear clutch gear 1 needle bearing 2 running 1986 thrust washer it has a loose fit a oil slots to the outside don t use 3 1987 ratio change a E 17T b L 18T ID by groove in teeth c taller 1st through 3rd Mainshaft 1 003 max bend 2 check with freewheeling gears and V blocks 6 Countershaft A B Ist gear smallest diameter gear 1 needle bearings Countershaft 2nd and 3rd gears 1 same ratio since 1957 2 M 906 gear diameter reduced running 1986 a must be used on 1100 b early or late style ok on 883 Countershaft 4th gear 1 step towards door thrust washe
130. ling gears What are the protrusions on the side of the gears e Dogs Freewheeling gears are locked to the shaft by dog to dog or dog to slot engagement Why are freewheeling gears used opposite fixed or sliding gears e Allows for constant mesh What are 3 different types of transmissions used in motorcycles e Direct drive e Indirect drive e Dual range In and indirect drive what shaft does the power come in on e Main shaft In and indirect drive all the drive gears will be on which shaft e Main shaft 13 14 15 16 17 18 19 20 21 22 23 24 25 How can first gear on the main shaft be identified e It s the smallest gear Which shaft rotates opposite to the mainshaft and allows for gear ratio changes e Countershaft In and indirect drive tranny all the driven gears are on which shaft e Countershaft The largest gear on the countershaft is part of which gear e First How does the power flow though an indirect drive transmission e Main shaft to counter shaft to final drive How does power flow through a direct drive transmission e Main shaft to counter shaft to main shaft to final drive What is the gear ratio in the top gear on a direct drive transmission e 1 1 What are 3 types of shift linkages that are used to transmit motion to the shift mechanism e Claw and pawl e Floating plate e Ratchet What is the purpose of the shift mechanism e To move the shif
131. lls A 12v battery will have 6 cells Lead sulfate will create a buildup of sulphation on the plates A fully charged lead acid battery will freeze at 75 degrees F A dead battery will freeze at 20 degrees F What gasses are produced during battery charging e Hydrogen and Oxygen 16 17 18 19 20 21 What is the purpose of a motorcycle AC charging system e To maintain a fully charged battery What components do AC charging systems consist of e AC generator e Rectifier e Regulator e Battery What are 3 basic types of charging systems based on output found on motorcycles e Y wave e full wave e three phase What is the main difference between an excited field and a permanent magnet charging system e The excited field can be turned off or on varied What are the basic components found in an electronic ignition system Source of EMF Triggering device Ignition Control Module Ignition coil Spark plug Switching device What are the 2 basic types of electronic ignition found on most of today s motorcycles e Capacitor Discharge Ignition CDI e Transistorized Pointless Ignition TPI HW Electrical Circuits 10 11 What are the 4 basic requirements for a functioning circuit Source Complete path Load device Means of control What is the definition of a load e A device that converts electrical energy into another form Name the 3 circuit conditions problems that could cause
132. ment devices Screw and Locknut Shim and Bucket Shim Bucket Hydraulic Eccentric What is valve lift and what is it measured in The distance the valve moves from the seat Measured in Inches of Millimeters What is vale duration and what is it measured in The time the valve is off the seat Measured in crankshaft degrees What is the function of the camshaft Change rotary motion into reciprocating motion Label the parts of the camshaft lobe A Nose B Flank C Clearance Ramp D Heel E Base Circle F Cam Lift Give a brief description of the parts that make up the camshaft lobe Nose Determines duration of max life Flank Determines the acceleration of opening and closing the valve Clearance Ramp Acts as a shock absorber when gently opening and closing the valve Heel Area that allows the valve to close Base Circle Forms the base of the cam constant radius from the centerline of the journal to heel What are 2 camshaft manufacturing methods Cast Billet List 3 different types of camshaft drives Chain Belt Gear List 3 different types of cam chain tensioners Manual Semi automatic Automatic 4 stroke operation Cylinder heads and Valves List the 5 factors that determine and engines efficiency and give a brief description of each e Volumetric Efficiency Percentage ratio comparing how much air fuel enters the engine to how much the engine would hold if it were 100 full e Com
133. n ID large cap 81 E82 to gear case ID small cap 80 and earlier had short piston and a rod to limit travel L82 has long piston to block relief hole when not running to prevent drain down rod deleted long piston is its own travel limiter also make a groove so oil can get to hydrolock passsage when retro fitting D Breather system 1 pressures positive piston moving downward negative piston moving upwards 2 function oil movement a pistons move downward breather valve window is open and flywheel area blows oil into the gearcase 1 gearcase area normally positive 2 cylinder area normally positive transfers through tappet guide holes b when pistons move upwards breather window closes and a negative pressure is created 1 flywheel area normally negative c there is a push pull effect which helps drain oil from the top end d oil seperator hole at bottom of breather trap feeds to hole in breather valve bore at the 5 o clock position connects with breather trap area holes align on negative pressure to draw oil from bottom of the trap e hole in breather valve at 9 o clock position is for primary oil return and should create a minimum of 25 water vacuum in the primary at 1500 RPM with vent line pinched dry clutch model 3 crankcase vent fitting located above oil pump connects to oil tank to prevent excessive pressure or vacuum 4 crankcase breather fitting lowest fitting on back of case
134. n additives in oxygenated fuels e Ethanol e Methanol e MTBE 9 What are some advantages of using gasohol e Burns cleaner e Raises octane rating e Good deicer 10 11 12 13 14 15 16 17 18 19 20 21 What are some disadvantages of using gasohol e Absorbs water e Can harm rubber cork and plastic fuel components e Can cause leanness Air fuel ratio can be defined as e A ratio be weight of parts of air to one part fuel What air fuel ratio does the theoretical perfect combustion of gasoline take place e 14 7 1 An air fuel mixture of 17 1 would be considered a lean mixture An air fuel mixture of 12 1 would be considered a rich mixture Cold starts require an air fuel mixture of 10 1 or less why e Fuel doesn t vaporize as well At idle the engine requires and air fuel mixture of approximately 10 1 why e Poor vaporization due to low air flow Mid range riding conditions will require an air fuel mixture of approximately 17 1 why e For better fuel economy and cleaner emissions To achieve best power and aid in cooling an air fuel mixture of approximately 13 1 would be required Define air density e The amount of oxygen molecules per given space What are 3 factors that can affect air density e Temperature e Altitude e Humidity If air density increases enough the carburetor must be jetted richer by increasing the jet size Gears Gear Ratios and Primary Drives 10
135. n some electric starting systems and primary drives a Electrical starting systems 1 Used to prevent damage to the starter motor 2 Starter drive disengages from the engine when the speed of the driven portion of the sprag clutch exceeds the speed of the starter b Primary drives NOVEMBER 10 12 1999 PAGE 8 1 Found in the multi plate wet clutch on some large displacement motorcycles 2 Operation Allows part of the clutch to slip when rider downshifts rapidly from a high RPM 3 Purpose It prevents the loss of rear wheel traction during engine compression braking 3 Some motorcycles and ATV s that are equipped with centrifugal clutches use a sprag clutch a Operation To provide some engine braking when the centrifugal clutch is disengaged b Purpose Helps to provide the rider with better control of the vehicle E Torque converter clutch Uses oil pressure for clutch and transmission engagement e SEE FIGURE 6 19 END OF CLUTCH NOTES NOVEMBER 23 1999 THEORY NOTES SUBJECT Cold starting systems and auxiliary circuits KEY POINTS 1 Cold starting systems A Purpose To provide excessively over rich mixtures less than 10 1 for cold starting purposes B Reason In cold temperatures fuel does not vaporize easily 2 Types of cold starting systems A Choke e SEE FIGURE 8 31 1 Plate located on the air filter housing side of the venturi 2 When on the plate restricts air flow enriching the air fuel mixture 3
136. ncentric Directly under the center of the venturi most common b Eccentric On the side of the venturi c Remote Not located on the carburetor connected by pipes or hoses 2 Most are made of aluminum 3 Most use an overflow tube Prevents fuel from flooding the engine if the float valve sticks open 4 Some have a drain screw 5 Must be vented to the atmosphere B Float 1 Floats on top of the fuel 2 Contacts the fuel valve needle and seat 3 Fuel flows until the float pushes the float needle shut and stops fuel flow to the carburetor 4 Construction material a Hollow brass b Hollow plastic c Solid plastic NOVEMBER 22 1999 PAGE 2 d Foam e Cork 5 Types of floats a Single A single float mounted on a pivot arm b Twin floats Two floats mounted on a common pivot arm c Independent Floats ride on independent pins but share a common pivot arm C Float valve assembly e SEE FIGURE 8 12 1 Parts a Float needle and seat 1 Normally made of brass 2 Usually numbered indicating flow rate 3 Can be either screw in press in or cast into the carburetor body b Float needle 1 Has a tapered tip that mates to the float needle seat 2 The tip may be made of aluminum chrome or viton 3 It normally has a spring loaded pin on the end that contacts the tang 4 The spring acts similar to a shock absorber 5 Most manufacturers recommend replacing the float needle seat and the float needle as a set 3 The volume of
137. ne temperatures cause poor vaporization of the fuel no heat B Idle 1 Requires a rich mixture of approximately 10 1 2 Reason Low intake air speeds cause poor vaporization of the fuel little turbulence C Midrange 1 Utilizes a lean air fuel mixture ratio of approximately 16 1 to 18 1 2 Produces the best conditions for good fuel economy and low exhaust emissions D Power 1 Requires a rich mixture of approximately 12 1 to 13 1 2 Allows the engine to develop good horsepower and operate at lower temperatures E Summary NOVEMBER 18 1999 PAGE 2 1 Ideal air fuel mixture requirements change to meet the different operating conditions 2 The job of changing ratios is handled by the carburetor or fuel injection END OF AIR FUEL MIXTURE NOTES NOVEMBER 19 1999 THEORY NOTES SUBJECT Carburetor basics KEY POINTS 1 The role of carburetor operation A To deliver the proper ratio of air fuel mixture to the engine in an atomized form B To provide a means of varying engine RPM 2 Principles involved in carburetion operation A Atomization Liquid drops suspended in air B The venturi effect 3 Carburetor fuel delivery circuits A Basic systems found on most motorcycles B Auxiliary additional systems found on some motorcycles 4 Basic circuits A Float bowl circuit B Idle circuit also called a slow speed or pilot circuit C Mid range circuit also called the intermediate circuit D Main jet circuit
138. neral e Synthetic e Animal e Vegetable 3 What are some of the special properties additives give the mineral base stock e Sulfur and Phosphorus for improved pressure properties e Zinc for improved sheer strength e Viscosity improvers e Anti foam agents 4 What are some advantages to synthetic oils e Better lubricant e Less evaporative e Can handle higher temperatures e Less viscosity change with temperature changes 3 What are some disadvantages with synthetic oil e Not to be used in new engines e Not to be used in engines with excessive tolerances e Can seep at seals e May not be compatible with some mineral base oils 6 What do the following abbreviations stand for e SAE Society of Automotive Engineers e API American Petroleum Institute T What property does the SAE rate e Viscosity 8 What is viscosity e Measurement of a fluids resistance to flow 9 What happens to oil as temperature drops e Thickens 10 11 12 13 14 15 16 17 18 19 20 what happens to oil as temperature raises e Thins Winter grade oil tested for flow ability at e Ator below Odegrees F Summer grade oil tested for flow ability e Ator above 210degrees F What do the letters in SAE 10W 40 stand for e SAE Society of Automotive Engineers e 10W winter weight of 10 e 40 summer weight of 40 What property does the API rate e Service duties What does the s in the API rating stand for
139. ng on a port 12 13 14 15 16 17 18 19 20 21 22 What is the purpose of the small vertical holes that may be found on the exhaust skirt of the piston e Aids in lubrication and cooling of the exhaust bridge What is are the main purpose of the 2 stroke piston rings e Seal the primary and secondary areas e Helps heat transfer Name 3 types shapes of piston rings e Standard rectangular e Keystone e Dyke How is the wristpin lubricated in a 2 stroke engine e Oil from the fuel mix lubricated through a slot or hole in the small end of the con rod The connection rod in a 2 stroke is usually of a 1 piece construction What type of bearings will be used at the small end with the wrist pin and at the big end with the crank pin e Small end Taper or needle bearing e Big end Roller bearing What is the purpose of the slots and holes in the connecting rod e Aid in lubrication What type of main bearings will most commonly be used on a single cylinder 2 stroke crankshaft e Caged ball bearings What is the purpose of the labyrinth seal used on multi cylinder 2 strokes e Separates and seals the primary chambers from one another What type of crankshaft is used in 2 strokes e Multi piece What types of crankcases are used on 2 stroke engines how can the cases be separated e Vertical or Horizontal split Why is it important that the crankcases be sealed airtight e The primary area c
140. nges Excessive heat needs to be removed thermal limits of engine g Kinetic energy Resulting from the combustion process and used to propel the motorcycle 5 EPA Extreme Protective Agency Emissions Standard A Since January 1978 motorcycles must comply with EPA emissions standards B NOx HC and CO are all monitored by the EPA OCTOBER 27 28 1999 PAGE 5 C Noise emissions and service procedures are also monitored by the EPA 6 Efficiency factors textbook page 19 A Volumetric Efficiency 1 Percentage ratio comparing how much air fuel mixture enters the engine to how much the engine would hold if were 100 full 2 Affected by intake timing intake part design and carburetion 3 Examples a Most stock engines operate at 80 to 90 efficient b Good tuning may produce 95 to 99 efficient c Turbo and supercharging can yield 140 to 160 efficient B Combustion efficiency 1 Percentage ratio comparing how much of the engine s original air fuel mixture has completed the entire combustion process 2 Affected by volumetric efficiency compression fuel quality combustion chamber design and ignition timing C Thermal Efficiency textbook page 25 heat efficiency 1 Percentage ratio comparing how much heat the engine produces to how much is used to produce power 2 Distribution of heat a Approximately 35 used to produce power b Approximately 35 leaves with the exhaust gases c Approximately
141. nimum of 12 hours C Check specific gravity of a battery after it has charged let sit for a couple of AMMO DS hours before checking 6 Battery charger type A Taper rate charger 2 4 6 8 ratings use 2 amp charge after first hour it should indicate 1 2 amp charge B Christie fixed rate charger good for bringing a dead battery back to life Servicing a used battery Visual inspection case and terminals Inspect battery carrier Check for sulphation and sediment flaking Connect battery tight clean connections 2 finger method use dialectric grease or petroleum jelly on terminals 1 loose connections cause voltage spikes that damage electrical components Battery testing A Check specific gravity with a hygrometer full charge is1 270 1 280 at 80 degrees 1 for every 10 degrees hotter add 004 points 2 for every 10 degrees cooler subtract 004 points 3 max cell variance is 050 points B Load testing wear safety glasses 1 formula 1 2 the cold cranking amps Jawe tech 2 Tech 2 2 minimum voltage at end of testing is 9 6 volts 3 don t test with a specific gravity of less than 1 240 4 check for bleeding with a multimeter a VDC scale b negative lead to negative lead of battery c positive lead to each battery cap bad is more than 2 2 VDC 5 voltage output can be done with battery in bike a turn ignition lights and accesories on b VDC scale minimum of 11 volts at terminals AIR FILTER SERVICING
142. nt coil separation distances e Progressive springs has a variable spring rate starting soft and finishing hard each spring has a different distance to the next spring What is the definition of Spring Rate e Amount of force needed to compress a spring a given distance What is a coil spring mean diameter e The line diameter across the spring What is an active coil e A coil that can move work What are 3 factors that affect spring rate e Material used e Wire diameter e Mean diameter e Number of coils Why can are 2 valve springs used for each valve e They help cancel out each other s vibrating harmonics What is coil bind and what can it cause e Coil bind is when the spring is compressed enough that the coils are touching full compressed and it causes Damage What is the coil springs free length e Lengths of the spring while sitting at rest uninstalled What happens when the valve floats e The valve is no longer in contact with the rest of the valve train What are the most likely causes of valve float e Weak Valve springs e Excessive RPM e Incorrect valve springs e Incorrect installed height What is the purpose of a rocker arm e Gain s mechanical advantage changes a direction of force and can open more than one valve at a time 20 21 22 What is the purpose of valve clearance Heat expansion Oil clearance Proper sealing Name 6 types of valve adjust
143. ntly convert chemical energy to electrical energy D Temperature 1 cold weather reduces retards the chemical reaction reducing performance 2 Overheating can increase corrosion of plates or cause plates to warp E Vibration excessive vibration can shake off active material from plates reducing battery life cell capacity and shortening cells Charging Systems 1 AC charging system A Purpose is to maintain a fully charged battery B Components 1 AC generator a Rotor 1 permanent magnet or 2 electromagnet b stator 1 1 2 wave or 2 full wave or 3 three phase 2 Rectifier a 1 diode or b 4 diode or c 6 or more diode 3 Regulator a suitable for permanent magnet system or b suitable for electromagnet system 4 Battery 2 Function A Ac Generator 1 Major parts stator and rotor a stator conductor stationary b rotor magnets rotating 2 Major divisions by charge curve and control a permanent magnet 1 rotor is permanent magnet type 2 charging curve abrupt moderate 3 regulator controls voltage by switching in to out gating to ground parts of the stator b excited field electromagnet 1 rotor is electromagnet type 2 charging curve is gradual high power 3 regulator controls charge by varying magnetic strength of rotor B Rectifier 1 Converts alternating current AC to direct current DC 2 Uses diodes C Regulator 1 Regulates charging system output to protect battery and elect
144. o fill container 5 Lighter for equal volume of liquid OCTOBER 27 1999 PAGE 3 6 Highly able to be compressed 3 Air agas A Air pressure 1 At sea level is 14 7 PSI 2 Decreases as altitude increases B Make up of air is 1 78 Nitrogen 2 21 Air 3 1 Inert inactive gasses C Air Density Amount of oxygen molecules per given volume of space thickness of air 1 Air density decreases a Occurs when altitude increases b Occurs also when temperature rises c Means fewer oxygen molecules d Results in rich carburetion 2 Air density increases a means more oxygen molecules b results in lean carburetion c air density increases in direct proportion to the pressure exerted upon it d Occurs when 1 Altitude decreases 2 Ambient air surrounding air temperature drops 4 Air Compression textbook page 17 gas laws A Air can be compressed B Laws based on Boyles Laws predict the behavior of compressed gas 1 Ifa gas or air is compressed the greater its temperature and pressure increases OCTOBER 27 1999 PAGE 4 2 The more air is compressed the greater its temperature and pressure 5 Pressure differences A Results in movement of a gas from the higher pressure area to the lower pressure area any matter in the way may be moved along with it B Examples 1 Weather 2 Carburetion 3 Induction phase 6 Laws and terms of motion A Velocity Speed of an object B Mass Weight of matter
145. o shell with clips for retention B installing and removing hub ruins bearing C hub nut must be torqued over tightening cracks taper area torque to 50 60 ft lbs use loctite 242 D check key height 119 max E clean taper with contact cleaner F updates 1 84A hub some problems noted in 91 and 92 a runs eccentric to shaft b not fully machined c splines to large for 84A steel plates 2 clutch problems 16 17 18 a misadjustment b wrong lubricant c low level lubricant d customers driving habits Transmission transmission top is removable in frame must move oil tank A 4 speed constant mesh sliding gear direct drive 1 to 1 ratio in 4th gear B history 1 36 Ist year of manufacture 52 E79 drum type shifter ratchet top L 79 85 flat plate shifter C lubricant H D Transmission Lube not sport transmission lube semi synthetic gear lube 1 good alternative 84 140 hypoid gear oil 2 quantity 24 ounces 3 4 quart 3 level indicator motorcycle must be upright and level a allen plug on cover b bottom of filler plug threads D venting flat plate shifter two holes in top cover 1 oil leaks at clutch tower usually indicates overfill or vent plugged Shifter mechanism shifter cam moves forks pawl arms move cam pawl carrier holds arms pawl carrier springs recenter carrier after shift shift shaft moves pawl carrier MOO gt Inspections A shifter plate inspection
146. of valve float harmonics of other spring d Total spring rate inner spring rate outer spring rate 2 Desmodromic a Mechanically closes the valves NOVEMBER 1 2 1999 PAGE 4 b Positive closing no chance of valve float c Uses a forked rocker arm and cam lobe to close the valve 4 Valve opening devices also called cam followers A Device that contacts the valve tip and is used to transfer power flow from the camshaft B Types e Rocker arm e SEE FIGURE 4 29 e Shim and bucket e SEE FIGURE 4 30 1 Rocker arm a A lever that can 1 Gain mechanical advantage 2 Change direction of force 3 Open more than one valve b Rocker arm designs 1 Cam contact under rocker arm change in direction of applied force e SEE FIGURE 4 22 2 Cam contact over rocker arm cam followers no change in direction of applied force 3 Push rod activated c Rocker arm ratio 1 Leverage that the rocker arm provides for lifting the valves 2 Indicates how much the valve is lifted off the seat compared to the cam lift 3 Computing cam lift Multiply ratio number X cam lift la Example Harley Davidson Iron XL with rocker arm ratio 1 42 1 and cam lifts is 0 375 of an inch To compute valve lift 1 42 X 0 375 0 5325 NOVEMBER 1 2 1999 PAGE 5 4 Computing rocker arm ratio la First divide valve lift by cam lift Harley Davidson Iron XL with valve lift 0 5325 and cam lift is 0 375 1b Then compute rocker arm ratio 0 5325 di
147. oil e Low voltage high amperage many thousands turns of wire that turns magnetism into electrical energy What are the 2 basic types of ignition coils e Collapsing field external e Rising field internal When is a high voltage produced in the secondary windings of a collapsing field ignition coil e When power to the primary coils is turned Off When is a high voltage produced in the secondary windings of a rising field ignition coil e When power to the primary coils is turned On What are 2 names for an electromagnetic switch e Relay e Solenoid What are 2 types of electromagnetic switches e Normally open e Normally closed What does an electromagnetic switch consist of e Coil of wire e Spring loaded plunger What type of relay will open its contacts when the relay is energized e Normally closed What type of relay will close its contacts when the relay is energized e Normally open Ignition Systems 1 Motorcycle ignition systems A Purpose is to provide and control the spark that initiates combustion B Today s systems are electronic C Basic components 1 Source of EMF 2 Triggering device 3 Ignition Control Module 4 Ignition coil 5 Spark plug 6 Switching device to turn off or on D Two basic types of electronic ignition 1 Capacitor Discharge Ignition CDI a AC Powered b DC powered 2 Transistorized Pointless Ignition TPI a analog fixed advance curve b digital variable advance curve E
148. oil control Explain how the piston ring end gap is measured e It s measured using a feeler gauge blade after fitting the ring into the cylinder What could happen if the ring end gap was too small e Could result in seizure What could happen if the ring end gap was too large e Could result in loss of compression and excessive blow by Why is it important to stager the piston ring end gaps during engine assembly e Supposedly it helps with preventing blow by at least initially What is the purpose of the wrist pin e Jt connects the piston to the connecting rod What is the correct placement of a wrist pin retainer circlip end gap e Should be installed with the clip end gap inline with the connecting rod Why is it important to always replace circlips with new ones e Circlips can be damaged and fatigued upon removal What is the purpose of the connecting rod e Transfers power from the piston to the crankshaft What type of connecting rod is found on a multi piece crankshaft and uses a roller bearing at the big end e A one piece connecting rod What type of connecting rod is found on a one piece crankshaft and uses plain bearings at the big end e A 2 piece connecting rod What should be done to the rod bolts and or nuts after disassembly e They should be discarded and or replaced What is the function of the crankshaft e It changes reciprocating motion into rotary motion What is a journal e A bearing support
149. osing Devices KEY POINTS 1 Definitions textbook page 42 50 A Active coil 1 Coils that can move work 2 More active the coils the softer the spring B Coil bind Spring that is fully compressed no distance between active coils Q Spring free length Total length of a spring at rest D Installed height Length of a spring when installed into a component E Spring pre load Amount of spring pressure exerted on component after it is compressed to its installed height F Spring fatigue Spring that is worn out Spring that is fatigued will not have proper free length G Valve float Point at which the valve does not stay in constant contact with the valve train 1 Usually caused by a Weak valve springs b Excessive engine RPM c Incorrect valve springs d Incorrect installed height H Spring harmonics Excessive valve movement speed creates vibration that matches spring vibration 1 Causes springs to stop moving NOVEMBER 1 2 1999 PAGE 2 1 Usually caused by over revving of engine 2 Coil Springs A Round or flat wire wound in a coil B Stores Kinetic energy C Spring rate 1 Amount of force required to compress a spring a given distance 2 Spring rate is normally expressed in pounds per inch Ib in 3 Example Spring rate 100 pound inch It takes 100 pounds force to compress the spring 1 inch 4 Lower spring rate reduces opening and closing wear of components 5 High spring rate ensures v
150. ospheric pressure Some states such as California require the fuel tank be vented into a charcoal canister What is the purpose of the fuel valve petcock e Delivers fuel from the tank to the carbs Name 4 different petcock styles used on motorcycles e Manual e Vacuum e Electric e Vacuum with electric assist What is the RES position used for on the petcock e To flow fuel to the carbs from a position in the tank lower than the pick up for the main or ON position How does a vacuum type petcock operate e Allows fuel flow only when the engine is running there s a vacuum present What is the PRI prime position used for on a vacuum type petcock e It flows fuel with no vacuum present all the time What is the purpose of the fuel pump e To deliver fuel from the fuel tank to the carbs fuel injection What are 3 types of fuel pumps used on motorcycles e Mechanical e Vacuum e Electric What is the purpose of the fuel filter e Filter crud from the fuel before getting to the carbs What is the purpose of the air filter e Filter crud from the air before getting to the carbs 13 14 15 16 Name 3 types of common air filters e Paper e Gauze w oil e Foam w oil What can happen to engine operation if one type of air cleaner is substituted for another filter of different construction that allows a different amount of air to flow e It can create a rich or lean running condition What are the
151. ot points shift linkage clutch lever locks and hinges and fuel valves IGNITION SYSTEMS 1 Battery point ignition BPI A Spark plug condition 1 broken porcelain detonation 2 shiny black coating oil burning 3 dry black coating rich condition 4 yellow deposits deposits burned to insulator B Coil wires 1 plug wire a visual inspection of insulation for cracking b terminal for looseness or corrosion c trouble shoot for bad wire using water mist wire will arc to ground 2 primary wire a terminals loose at coil b bad connection of wire to terminal 3 Ignition coil a inspect for cracks at mounting area b plug wire terminals and primary wire posts C Points Condenser 1 inspect contact points replace if pitted across more than 1 3 of surface replace if any damage is noted or if rubbing block is worn 2 always replace condenser when replacing points tech 2 Tech 2 3 advancer mechanism typical high wear areas springs pins shafts and weights typical damage area small locating pin at cam pin 2 Maintenance A Spark plug gaping 1 bend side electrode to adjust 2 do not use automotive style adjuster use wire gauge 3 adjust gap to 028 032 B Advancer lubricant 1 light adequate lubrication of all moving parts with anti seize C Points cam lubrication 1 light coating of H D hi temp grease p n 99862 72 A Rear cylinder fires first B Point cam wide lobe rear cylinder narr
152. otor sprocket nut A it was first a grade 2 hex nut B than a grade 5 hex nut C now a grade 8 nut with a flange D torque to 150 165ft lbs Use Loctite 262 Source of oil leaks at primary gasket surface shift shaft seal to cover foot peg shaft starter motor clutch cable screw adjuster mm 0 p CLUTCH XL 4 SPEED General A snap ring assembly B can be removed piece by piece or as a complete assembly C use a clutch spring compressor for disassembly Clutch spring A diaphragm same strength as old double coil B special washers round edge to spring Clutch A fiber friction drive 1 010 max warpage 2 130 minimum thickness 3 when installing new soak in oil for at least 5 minutes B steel driven 1 010 max warpage 2 060 minimum thickness 3 stamped steel smooth rounded edge faces out 4 Spring plate A check for loose rivets B measure for variance max of 020 5 Rotor A part of clutch shell assembly magnets are fragile 6 Clutch hub bearing A beefed up L86 reduces looseness ACCESS DOOR XL 4 SPEED 1 Stator mount 2 Torx screws A 30 40 in lbs B loctite encapsulated on threads 3 Before removal measure transmission shaft end play 4 To remove access cover shock dowel pins or heat around dowel pins TRANSMISSION XL 4 SPEED General A 4 Speed B Direct drive C 1 to ratio in 4th gear D Sliding gear E Sprocket 21T Right hand threads 65
153. ough a passage to the discharge nozzle 3 In multi cylinder multi carburetor engines one accelerator pump is used to feed all the carburetors in most cases 3 Air cut off valves e SEE FIGURE 8 21 a Purpose To prevent engine back firing during rapid deceleration NOVEMBER 23 1999 PAGE 3 b Operation 1 During rapid deceleration a very strong engine vacuum is developed 2 Strong engine vacuum moves the piston to block or reduce air flow through the idle air bleed passage 3 The idle circuit then becomes rich preventing engine backfire 4 Power jet also called thunder jets Found on some motorcycles and snowmobiles a Power jets will enrichen 7 8 to wide open throttle to supplement the main jet b Allows better transition from mid range to full throttle c Main jet 1 Primary fuel source from to 7 8 throttle 2 Can be leaner for better transition better response than systems without a power jet d Parts 1 Fuel jet Located in the float bowl or discharge nozzle 2 Discharge nozzle Located in the mouth of the carburetor 3 Fuel line from the float bowl to the discharge nozzle 4 May have an air bleed in the discharge nozzle assembly e How it works pressure differences 1 At 7 8 throttle the air velocity is great enough to reduce pressure at the discharge nozzle to cause fuel to be pushed up from the float bowl 2 Provides additional fuel to the main jet at 7 8 to full throttle END OF COLD STARTING SYSTEMS AND AU
154. ow lobe front cylinder 4 Ignition timing A Point gap set gap on wide lobe 018 check gap on narrow lobe should be 018 002 if not recheck advancer for wear or misalignment on cam 5 Static timing A Set point gap on wide lobe than check point gap on narrow lobe B Time off of front cylinder advance back engine 1 2 of piston travel to find front cylinder advance mark C Disconnect coil wire to points D Use diode check on meter set advance plate where beeping from meter is intermittent with points advanced 6 Check dynamic timing with a timing light A 2000 RPM for BPI system B Adjust plate not points 7 Electronic ignition A Inspection 1 plugs wires coil same as BPI 2 VOES vacuum operated electrical switch a vacuum switch b requires a good ground c check for damage B Types 1 Ist year 78 1 2 80 Prestolite points cam mechanical advance adjust air gap 004 006 with a brass feeler gauge 060 065 XL s 2 80 E 83 XL 80 84 big twin Magnavox stage I electronic ignition coil electronic advance 6 wire system 3 to sensor plate 2 to coil 1 to ground 3 L 83 and up XL 84 and up big twin Magnavox stage II VOES 7 wire system voilet wire to VOES C V O ES 1 grounded advanced high pressure 2 ungrounded retarded low pressure mode throttle position load voes violet wire tech 2 Tech 2 advance economy 1 8 1 4 high closed on gro
155. pair of 120 degree crankshafts 3 Crankcases A Purpose Contains 1 Crankshaft 2 Sometimes a Oil pump b Primary Shaft c Primary drive d Main shaft e Counter shaft f Transmission shaft g Cam shaft B Four stroke crankcases must be vented to the atmosphere Today EPA requires crankcases to re circulate back through the combustion chamber C Types are 1 One piece Case is all one piece uses an access cover to remove parts 2 Vertical split Cases separate vertically Must remove cylinders before case halves can be split 3 Horizontal split Cases separate horizontally Bottom halves can be removed with cylinder s attached END OF FOUR STROKE ENGINES CRANKSHAFTS AND CONNECTING RODS NOTES OCTOBER 29 1999 THEORY NOTES SUBJECT Four stroke engine Cylinder Heads and Valves KEY POINTS 1 Cylinder Heads A Constructed of aluminum alloy or cast iron 1 Cast iron a Advantages 1 Dissipates heat well 2 Easy to cast in a mold 3 Aluminum alloy a Advantages 1 Lighter in weight 2 Dissipates heat 2 to 2 1 2 times faster than cast iron b Disadvantages 1 Does not wear as well 2 Needs special valve seats and guides B Squish quench area 1 Area on the cylinder head that forces the air fuel mixture into a tight pocket under the spark plug 2 Purpose increases combustion efficiency e SEE FIGURE 3 11 C Multi valve cylinder heads Intake valve area is usually larger than the exhaust valve area
156. pump e Power jet e Air cut off valve What is the purpose of the accelerator pump and when does it operate e It prevents temporary lean conditions during rapid throttle opening What controls the opening of the accelerator pump e Throttle linkage Where is the accelerator pump nozzle located e Air cleaner side of the slide What is the purpose of the air cut off valve e Prevents engine back fire during deceleration What controls the operation of the air cut off valve e Strong engine vacuum What is the purpose of the power jet e Better transition from midrange to full throttle Where would the discharge nozzle of the powerjet be located e Mouth of the carb on the air cleaner side What controls operation of the power jet e Reduced air pressure from 7 8 to WOT 4 Stroke Cylinders to Crankshaft 10 11 12 What are 3 purposes of the cylinder e Guide piston travel e Aids in heat transfer e Thrust surface for piston skirt Name 3 types of cylinder construction e Cast Iron e Aluminum with steel cast iron sleeve e Coated aluminum What are 2 purposes of the cross hatch pattern in the cylinder bore e Helps the rings seat e Place for oil to hold for lubrication Why are at least 6 measurements needed when measuring a cylinder e To check for out of round or taper in the cylinder What is the purpose of the piston e Transfers power to the connecting rod forms the floor of the combustion chamber
157. purpose of these areas that make up the poppet valve e Tip area that rides against the opening device Keeper groove groove that locks the keeper and spring retainer Stem thrust surface for the valve guide Face area that mates to the valve seat Margin supports the face Which valves will normally provide the larger valve area for the airflow e The intake valve s Where is Stellite used and why e Tip and Face to help with wear 23 24 25 26 27 28 What areas of the valve should be closely inspected for wear e Tip e Keeper Groove e Stem e Face What does the face of the valve seat against e Valve seat What can cylinder head valve seats be constructed of and why e Hard alloy steal to deal with heavy wear What is the purpose of having 3 different angle on the cylinder head valve seat e Better flow characteristics What is the bushing that is used to support the valve called and what is its construction e Valve guide can be made of either Cast Iron or Brass The purpose of the valve stem seal is e Prevent excessive oil from entering between the valve guide and the valve stem Air and Fuel Delivery Systems 10 11 12 The purpose of the before and after carburetor air fuel delivery system is to e Before store and deliver proper amounts of air and fuel e After deliver air fuel to the engine If fuel is to flow from the fuel tank the fuel tank must be vented to atm
158. r 2 1987 ratio change a E 27T b L 26T grove on face of gear 3 flip KM transmission plate over a measure from end of splines to slider b use chart in manual to determine washer size End play 1 mainshaft 006 020 no preload 2 countershaft 004 015 use spoke to pull on shaft 3 proceedure a b c d install without washers measure end play and write it down use charts in manual to determine washer size reassemble and double check door bolt torque 14 ft lbs HW Batteries Charging amp Ignition Systems 1 10 11 12 13 14 15 What does a battery do e Stores DC acts as an electrical buffer supplements power at low RPM provides power to start the motorcycle What are the 3 basic types of batteries used on motorcycles e Conventional e Low maintenance e Maintenance free How much voltage is each cell capable of producing e 2 1 2 1volts What are 5 different components required to make up a wet cell lead acid battery Negative plates Positive plates Separator sheet Electrolyte Case What is the composition of the battery electrolyte e Diluted sulfuric acid and distilled water The plates in each cell are connected in parallel The greater the number of plates in a cell the higher the current output The cells in a battery are connected in series Connecting the cells in a series will allow for a higher voltage output A 6v battery will have 3 ce
159. r lobed inner rotor usually la Inner rotor in eccentric with outer rotor 1b Inner rotor rotates within the outer rotor 2 Gear Uses two spur gears meshed together 3 Plunger Uses a reciprocating piston in a cylinder la Up stroke draws oil into the cylinder lb Down stroke pressurizes the oil lc Uses a check valve to insure proper direction of oil flow 2 Oil pressure relief valve a Usually located near the oil pump b Purpose To prevent excessive oil pressures c Bleeds off excessive oil to the crankcase d Usually actuated during cold starts or excessive engine RPM s 3 Oil filter by pass valve a Usually located in or near the oil filter b Ifthe filter clogs the by pass will open allowing the oil to by pass the oil filter 4 Oil filters Four types a Paper uses treated pleated paper can be a spin on or cartridge type b Fiber traps contaminants through out the filter not just on the surface area c Screen or wire mesh a screen or metal mesh traps the large particles NOVEMBER 16 17 1999 PAGE 6 d Centrifugal Engine oil is spun at crankshaft speed Dirty oil is heavier and is trapped within a canister 5 Other types of lubricants A Grease 1 Generally a lubricant suspended in gel 2 Purpose To lubricate in an area where oil liquid can not be contained 3 Examples White lithium mineral oil based or molly lube 4 Used in areas such as wheel bearings steering head bearings and swing arm bearings B
160. radial loads e Needle bearings e Plain bearings What is an advantage of a caged bearing over an uncaged bearing e Can support higher RPM What type of bearing requires a thin layer of oil between it and the rotating surface and usually comes in matched pairs e Plain bearing What is imbedability e The ability to imbed small amounts of material 12 13 14 What are the purposes of thrust washers and bearings e Support axial loads and reduce shaft end play What is the main difference between a thrust washer and thrust bearing e Thrust bearing has rollers What is a bushing e Soft alloy that works similar to a plain bearing Fuels amp Air Fuel Mixture Requirements and Air Density 1 What is the importance of a fuels octane rating e Measurement of the ability to resist detonation 2 What are some factors that can influence the octane requirements of an engine Air temperature Altitude Humidity Ignition timing Jetting Method of riding e Engine compression ration 3 Gasoline is basically made up of Hydrogen and Carbon atoms called hydrocarbons 4 3 types of gasoline are e leaded e unleaded e oxygenated J Why has leaded gasoline been replaced e EPA regulations due to pollution 6 What are 2 additives used to increase unleaded fuels quality e Iso octane e Heptane re What is the main purpose of oxygenated fuels e Burns cleaner and raises octane rating 8 What are the 3 most commo
161. rator pump 2 Mid range ports B Mid range circuit sometimes called intermediate circuit 1 Operation Main effect throttle opening to throttle opening 2 Parts a Continues to use the idle circuit b Some may have an air bleed passage with a mid range air jet c Mid range fuel jet 1 A brass insert or a precisely drilled hole in the carburetor body 2 Used to meter the fuel during the mid range operation d Mid range outlet port Allows air fuel flow when uncovered by the throttle plate at about throttle opening C Main jet circuit also called a high speed circuit 1 Main effect a If the carburetor has a mid range circuit 34 throttle to full throttle b Ifthe carburetor does not have a mid range circuit 4 throttle to full throttle opening c Parts 1 main air jet Allows flow of air to the main bleed tube 2 Main fuel jet 3 Main air bleed tube emulsion tube NOVEMBER 23 1999 PAGE 3 la Located in series between the main fuel jet and the main outlet nozzle lb Aids in atomization by mixing air with fuel 4 Main outlet discharge nozzle Located in the center of the venturi END OF FIXED VENTURI CARBURETOR NOTES NOVEMBER 22 1999 THEORY NOTES SUBJECT Float bowl circuit KEY POINTS 1 Purpose A To maintain a constant volume of fuel in the float bow at all engine RPM s 2 Parts of a float bowl A Float bowl 1 Attached to the carburetor body by screws or a wire spring clip a Co
162. re monitored by the EPA in motorcycles e Oxides of Nitrogen Nox e Hydrocarbons HC e Carbon Monoxide CO The EPA also monitors e Noise emissions e Service procedures Hydrocarbons are the result of e Unburned raw fuel 42 43 44 45 Carbon monoxide is the result of e Partially burned fuel Carbon dioxide is the result of e Complete combustion How hot can the combustion chamber gas temperatures reach e Up to 4000 degrees F Combustion chamber pressures can reach e 800 1 000 PSI Tech 2 Batteries 1 Penned in date on top should not sit on shelf for over one year see service bulletin M1020 A Number year B Letter month C Example 8L Dec 88 Late model chart for battery coding see hand out Putting battery into service Take off vent plug Remove cap farthest from vent set on hole Install vent tube blow in tube it should move the cap Check strength of the electrolyte it should be 1 265 1 270 Fill each cell with electrolyte to lowest level set aside for 30 minutes Rock battery to release trapped air and fill to upper level Charge battery at 1 10 amp hour rating until fully charged full charge is 1 270 1 280 specific gravity Battery type A 19 amp black with yellow caps B 22 amp white with green caps C 32 amp black with green caps Battery data A Conventional charge a minimum of 6 hours max temperature of 113 degrees F B Low maintenance charge a mi
163. re positive engagement than wet clutch 4 Dry clutches normally use an organic or kevlar friction material 3 Two styles wet or dry a Single plate normally found on dry 1 Major components la One friction plate 1b Diaphram spring lc Inner pressure plate ld Outer pressure ring 2 Automotive style 3 Used mostly as a dry clutch b Miulti plate 1 Major components la Outer clutch basket 1b Disk stack that consists of alternating friction and metal plates lc Inner clutch hub ld Pressure plate le Springs 2 Can be made smaller in diameter 3 Can be a wet or dry clutch 4 Parts of the multi piece clutch a Outer clutch basket NOVEMBER 10 12 1999 PAGE 3 1 Part of the primary drive 2 Driven by crankshaft primary shaft 3 Free wheels on the transmission main shaft 4 Rotates anytime that the engine is running 5 Most use shock hubs la Absorb an excess flow of power 1b Springs or rubber dampers b Drive plates 1 Connected to and driven by the outer clutch basket shell 2 Has tabs on the outer edge 3 Tabs fit into the basket fingers 4 Rotates anytime the outer clutch basket is rotating 5 Can be a friction or metal plate c Driven plates 1 Connected to and drives the inner hub 2 Driven by the drive plates 3 Anytime the driven plates are rotating the inner hub is rotating 4 Can be either friction or metal plates d Inner hub 1 Driven by the driven plates 2 Splined to the transmission main s
164. re the same as the ball bearings 4 Main advantage Tapered roller bearings can handle radial loads 5 Handles axial loads in one direction only Precision insert bearings plain bearings 1 Hasa hard steel shell with a very soft babbit material inner liner 2 Babbit inner liner A mixture of various metals such as tin alloys lead silver antimony and copper 3 Has imbedability The ability to imbed small amounts of small material 4 Has conformability The ability to conform to variations in shaft alignment and journal shape 5 Purpose To prolong the life of the shaft journal 6 Normally a two piece bearing matched in half shells 7 Come in various thicknesses to allow for manufacturing tolerances 8 Lubrication requirements a A constant film of oil flowing between the journal and bearing so that there is no metal to metal contact b High oil pressure 9 Receives most of its wear during cold starts before oil flow is sufficient to protect the bearing 10 Major advantage Can take high radial loads due to the amount of surface area of liquid liquid can not compress Thrust bearings 1 Looks similar to a flat washer with cylindrical rollers or spherical balls attached to it 2 Purposes a Support axial loads NOVEMBER 18 1999 PAGE 4 b Reduce shaft end play 3 Main advantage Can perform both purposes Thrust washer shim 1 Machined surface flat washer 2 Usually made of hardened steel or steel wi
165. rial examples 1 Silicon most common 2 Germanium older 3 Selenium obsolete C Examples of semi conductors used on motorcycles 1 Diode a Two leads b Flows current in one direction c Blocks flow in opposite direction 2 Transistor a Three leads b A fast low current switch 3 Silicon controlled rectifier a Three leads b A slower high current switch 8 Current A The rate of FLOW of electricity B Measured in amperes Amps 1 AMP 1 Coulomb 1 Second 1 A coulomb is 6 24 x 1018 electrons 2 So 1 amp is a flow of 6 24 x 1018 electrons per second 6 240 000 000 000 000 000 electrons 9 Resistance A Opposition to current flow electrical friction B Measured in Ohms C The higher the opposition to current flow the higher the resistance 1 A component with 4 Ohms of resistance permits a lot of current flow 2 A component with 10 Ohms of resistance permits less current flow D A switch wire or fuse in good condition has 0 Ohms of resistance 10 Watt A A measurement of electrical power Force x Distance work Time Power Pound force x Feet distance Torque Seconds time Horse Power Volt force x Coulomb distance Second time amp Watt power 1 Volt x 1 Amp 1 Watt E EMF VOLT Pressure I Intensity AMP Rate of flow R Resistance Ohms P 11 A B 12 A B 1 a b c d 2 a b Power WATTS Electrical H P Polarit
166. rical components 2 Does this depending on whether permanent magnet or electromagnet by a gating excess current to ground draining off part of stator or b by moderating voltage to the field coil rotor thereby changing the strength of it s magnetism D Battery 1 stores DC 2 Acts as a buffer between charging system and electrical components 3 Powers components at low RPM when charging system output is low E Three charging system designs based on output 1 Ywave system a small charging coil grounded on one side other goes to rectifier b very low pulsating output 2 Full wave system a Both ends of the larger charging coil go to the rectifier b Moderate output 3 Three phase system a 3 interconnected charging coils 3 coil leads going to the rectifier b high smooth output Clutches 10 11 12 What is the purpose of the clutch e To engage and interrupt power flow from the engine to the transmission What are 5 types of clutches Manual Centrifugal Variable ratio Sprag Torque converter How is a manual clutch engaged and disengaged e Typically by the rider pulling on a lever on the handlebar What types of friction material are used on a wet clutch e Cork neoprene paper or kevlar What types of friction material are used on a dry clutch e Kevlar or organic What part of the multi plate clutch is usually driven by the engine crankshaft e Outer basket What shaft do most clutch baskets rot
167. ring e Thrust washers e Bushings A Ball bearings 1 Good all purpose bearing 2 Can handle axial and radial loads NOVEMBER 18 1999 PAGE 2 3 Requires very little lubrication if over lubricated the spherical balls will hydroplane 4 Parts a Spherical balls b Inner race normally a press fit on to the shaft c Outer race usually pressed or pinned into place d Cage sometimes 1 Prevents the spherical balls from touching each other 2 Can be operated at higher RPM s than uncaged 5 Uncaged ball bearings can handle higher loads because they have more surface area B Roller bearings 1 Similar to ball bearings except it uses cylindrical shaped rollers instead of spherical balls 2 Lubrication requirements are the same as the ball bearings 3 Main advantage Has more surface contact area than ball bearings and therefore can handle higher radial loads C Needle bearings 1 Similar to a roller bearing except the needle bearing has a higher aspect ratio ratio of length to diameter than a roller bearing 2 Lubrication requirements are the same as the ball bearings 3 Main advantage Can support very high radial loads 4 Cannot a Support axial loads b Handle high RPM s D Tapered roller bearings 1 Similar to roller bearings except the inner and outer races are tapered at an angle 2 Tapered roller bearings are normally used in pairs with opposing angles NOVEMBER 18 1999 PAGE 3 3 Lubrication requirements a
168. rocket b The main drive gear and drive sprocket free wheel on the main shaft c Power flow 1 Power flow enters on the main shaft 2 Transfers to the countershaft 3 Then exits the main drive gear 6 Parts of the transmission A Shift linkages 1 Hand or foot operated linkages that moves the shift mechanism 2 Types a Claw or pawl b Floating plate e SEE FIGURE 6 26 c Ratchet e SEE FIGURE 6 27 B Shift mechanisms e SEE FIGURE 6 25 1 Purpose To move the shift fork 2 Types a Shift drum 1 A round drum with square sided grooves that guides the shift fork 2 Most common b Cam plate NOVEMBER 15 16 1999 PAGE 5 1 A flat plate with square sided grooves that guides the shift fork C Shift forks 1 Purpose To move the slider gear 2 Shift forks are made of a Bronze alloys b Steel 3 Shift forks are normally coated with a hard surface i e flash chromed 4 Shift forks can be damaged by a Bent b Burnt c Broken 5 Important Always replace a damaged shift fork D Shift detents 1 Purposes a To help locate next gear b Helps keep transmission in gear by preventing the shift mechanism from rotating accidentally 2 Types a Arm and roller b Spring and ball c Spring and plunger 7 Shifting sequence A The foot moves the shift linkage B The shift linkage moves the shift mechanism C The shift mechanism moves the shift fork NOVEMBER 15 16 1999 PAGE 6 D The shift fork moves the
169. rom each other 4 electrolyte a amix of diluted sulfuric acid and distilled water 5 case a contains all parts of the cells b usually made of plastic or hard rubber C Plate arrangement 1 in each cell plates are wired in parallel 2 each plate increases the current while the voltage remains the same D Cell arrangement 1 Cells are wired in series 2 Each cell increases the total voltage output while current remains the same a 12v battery has 6 cells b 6v battery has 3 cells E Ohms Law 1 Size of cell affects current but not voltage 2 Number of cells affects voltage but not current 5 Discharging A The electrolyte breaks down forming water and sulfuric acid 1 Sulfuric acid combines on the negative plates and forms lead sulfate 2 After atime buildup becomes visible as a white crystalline substance called sulphation B Plain water is left on the positive plates 1 electrolyte becomes similar to water and is prone to freezing 2 Adead battery will freeze at 20degrees F 6 Recharging A The chemical process is reversed B Bubbles visible during charging 1 excess hydrogen and oxygen that could not remix 2 Free gassing or hydrogenating 3 reason batteries are vented 4 Danger Hydrogen and oxygen gasses given off during free gassing are highly explosive C With electrolyte in full suspension fully charged lead acid batteries resist freezing down to about 75degrees F 7 Ampere hour rating A Battery ability
170. s 1 bent or worn more than 010 replace 2 check for smooth fimger movement 3 do not re use snap ring B pawl arm inspection 1 hook area wear 2 pawl spring wear C pawl carrier inspection 1 broken or out of place causes limp shifter D cam follower inspection 1 bad spring ID cad plated too stiff coil binds 2 good spring ID black P N 34068 52 E shifter shaft inspection 1 popping out of groove use washers to shim 19 Sprockets A left hand threads 1 mainshaft clutch hub nut and sprocket nut B lock brake or lock in 2 gears to remove sprocket nut C tab washer lock 83 and earlier 1 early style lock bend tab only once 2 torque nut to 80 90 ft lbs and use locktite 262 D allen lock 83 and later 1 torque nut to 80 90 ft lbs 120 max 2 allen screw location must prevent nut from loosening 3 retro s to all 80 models E sprocket types dished 36 79 installs with dish towards transmission 80 85 flat F sizes 22 24T Ok for clearance to tranny 25 26T may require machining the case for clearance 20 Kicker cover A spring and shaft align tab at 5 o clock position B kicker gear dowel align at 7 o clock position 1 when together in the case the dowel and the tab are aligned 21 Starter clutch and outer gear has rectangular keyway A starter clutch gear 2 ratios 1 early 14T discontinued 2 late 16T more leverage 22 Shifter forks A shaft e clip
171. s of 0 05 mm F Three types la Shim over bucket Low RPM usage 1b Shim under bucket High RPM usage must remove cam to replace shim lc Bucket High RPM usage must remove cam to replace shim NOVEMBER 1 2 1999 PAGE 7 c Hydraulics e SEE FIGURE 4 28 1 Automatically adjusts for the proper clearances 2 Uses oil pressure to maintain zero lash at all engine temperatures 3 Disadvantage Rare but they can collapse if air or dirt enters the adjuster oil contamination 4 Types are la Hydraulic lifters example Harley Davidson 1b Hydraulic adjusters example Suzuki GS or Honda GL models d Shim 1 Used with rocker arms 2 Shim sits in a pocket on top of the valve stem or on the valve stem 3 Some Kawasaki s and Ducati s have this style e Eccentric 1 Used with rocker arms 2 Rocker arm pivot shaft is ground off center elliptical cam ground 3 Adjustment rotate pivot shaft so that clearance between the rocker arm and the valve tip is changed 4 Pivot shaft is held in place by a lock nut 5 Cam shafts A Purpose of the camshaft 1 Change rotary motion to reciprocating motion 2 Mechanical timer for the valves that controls a When to open b How fast to open NOVEMBER 1 2 1999 PAGE 8 c How far to open along with rocker arm ratio d How long to stay open e When to close f How fast to close g How long to stay closed B Valve lift Defined as the distance the v
172. side then press in new bushings Pushrod tubes a 1986 1990 i multipiece tube ii both top and bottom seal against an o ring Cylinder Head a Early 883 egg shaped chamber and sand cast b Late 883 round hemispherical shaped chamber die cast c 1986 to early 1987 1100 egg shaped chamber sand cast d Late 1987 1100 and all 1200 round hemispherical shaped chamber die cast e Late 1100 heads were milled 0 040 i That milling did not continue on the 1200 Torque pattern gt gt gt Front cylinder 1 8 turn at a time Torque to 7ft lb then 14ft lb Rear cylinder Then turn 1 4 turn 90degrees 10 Early head bolts have large spacers later ones have a flange built onto the stud changed 90 91 a Lightly oil bolt after cleaning used as anti seize 11 Rocker arm bolts longer bolt is on the pushrod side 12 Valves a 883 has the smallest b 1100 from 1986 to early 1987 were the same as the B T 1340 valves c 1100 in late 1987 decreased diameter of valves i Late 87 1100 and all 1200 valves are the same size ii The change resulted in better mid range d XL s have longer valve stems than B T e There are no service values available 13 Cylinders a Different castings between the 3 different motors i 883 1100 and 1200 stamped into bottom right corner of cylinder ii cylinders are all the same length and use the same sleeve iii sleeve is just bored out more for the larger displacement 1
173. side of caliper and pad a purpose of half shim is to clean rotor and pad J Discs 1 damage max warp 008 max runout 008 dial indicator mounted to front fork leg and spin disc thickness minimum thickness is stamped on the rotor check in at least four places with no more than 002 variance 2 rotor is the only part with the part number stamped on it hand out pages 5 17 to 5 21 bulletins on brakes and pads K Disc and pad sets DISC PAD 73 mild steel organic 78 hard stainless semi iron black color 79 very hard stainless semi iron copper 84 very hard stainless 11 12 rotor semi iron copper 84A 30 hole anti symmetrical semi iron copper 94 softer stainless semi iron gray BRAKE FLUID 1 Description Dot 3 glycol based clear hygroscopic eats paint and plastic 5K miles have no markings has 3 4 mark Sep 76 service internal components cup inside master cylinder Dot 5 silicone based purple aerates won t harm paint or plastic 15K miles 2 yellow and 1 white dots has 750 mark note when you have metal to rubber use Dow Corning 44 for metal to metal use anti seize BANANA BRAKE 1 72 E 80 caliper body is the same for front and rear differance is in the piston 3 pistons 3 retraction rates color painted on pucks A Plain front B Red front or rear C Gold rear most retraction 3 Changes A 771 80 wave washer was added to aid in retraction
174. skets c May not be compatible with mineral base oils C Animal base oils 1 Fish or whale oils 2 Good anti foaming lubricant 3 Mostly used as a hydraulic oil in suspension systems 4 Not very long lasting rots with age D Vegetable base 1 Castor bean oil 2 Excellent lubricant used mostly in two stroke engines pre mix 3 Disadvantages a Separates from gasoline NOVEMBER 16 17 1999 3 PAGE 3 b Short shelf life once exposed to oxygen c Will not store in pre mix form Oil classifications two main agencies that classify oil e S A E Society of Automotive Engineers e A P I American Petroleum Institute A SAE rates the viscosity of oils as follows e SEE FIGURE 7 3 1 Summer oil a The flow rating of the oil is tested at a very high temperature generally 210 degrees Fahrenheit or more 1 Example 20 30 and 40 weight oils 2 Winter oil a The flow ability of the oil is tested at a very low temperature generally 0 degrees Fahrenheit or less 1 Example 10w 15w 20w and 30w oils 3 Multi grade oils a The flow rating of the oil is tested at low and high temperatures 1 Example 10w30 indicates the oil has a flow characteristics of a 10 weight at 0 degrees Fahrenheit and a 40 weight at 210 degrees Fahrenheit B A P I rates the service duties of oil as follows 1 S indicates a spark engine and C indicates compression a diesel engine 2 SA Mild conditions no additives
175. slider gears 8 Dual range transmissions sub transmissions A Auxiliary transmission placed into power flow between the transmission and final drive system B Normally a two speed transmission high and low C Normally uses a manual shift gear box D Usually consists of 1 Input shaft 2 Output shaft 3 Four gears 4 Shifting fears 5 Shift detent 6 Shift mechanism 7 Shift linkage 8 Optional Damping device E On small trail motorcycles this transmission provides dual range gear ratios for on and off road use F On larger heavier touring motorcycles it provides quick acceleration in stop and go traffic in the low range and a high range for cross country touring and good fuel economy END OF TRANSMISSION NOTES NOVEMBER 8 9 1999 THEORY NOTES SUBJECT TWO STROKE ENGINE PARTS KEY POINTS 1 Cylinder head A Purposes 1 Seals the combustion chamber 2 Locate the spark plug usually in the center of the combustion chamber 3 Aid in heat transfer air or liquid cooled 4 Provide the shape of the combustion chamber 5 Provide the squish band B Squish bands 1 Purpose Concentrate the fresh charge in a tight pocket under the spark plug 2 Serves two purposes a Reduces end gasses which helps decrease detonation b Creates a turbulence which helps cool the secondary area 2 Cylinders A Purposes 1 Guide piston travel 2 Sealing surface for the piston rings 3 Locate the exhaust and transfer ports
176. soline 50 1 or 32 1 e 32 1 33 34 35 How would changing from 20 1 to a 50 1 mixture effect the richness leanness of the air fuel mixture e It would be very rich more gasoline What determines how much oil is injected on an oil injection lubrication system e Engine RPM e Throttle position What are 6 causes of 2 stroke engine seizure Lean causes excessive heat Lack of or to much lubrication Excessive load on engine Improper clearances Improper timing Cold seizure improper warm up 2 Stroke 1 What are the 3 major moving parts of a 2 stroke engine e Piston e Con rod e Crankshaft What is used to control the airflow in through and out of the engine e Ports intake transfer and exhaust What are 4 advantages of the 2 stroke compared to the 4 stroke e Better mechanical efficiency e Weight loss e Power stroke every revolution of the crankshaft e Typically more power than same size 4 stroke What are 4 disadvantaged of the 2 stroke as compared to the 4 stroke High HC emissions Poor fuel economy Higher operating temperatures Excessive and high frequency vibration What are the 3 main ports in a 2 stroke cylinder and what are their purposes e Intake draws in fresh air fuel charge e Exhaust Removes spent charges e Transfer moves the fresh charge from the primary compression area to the secondary compression area In a piston port 2 stroke what part of the piston controls
177. ssions 1 2 e SEE FIGURE 6 22 Power enters one shaft and leaves on another shaft on a different axis Uses at least two shafts a Main shaft 1 Splined to the clutch inner hub 2 Power flow usually enters on the main shaft NOVEMBER 15 16 1999 PAGE 3 b Counter shaft 1 Rotates opposite of the main shaft 2 Power flow generally exits on the countershaft 3 General rules of indirect drive transmissions a All gears on the main shaft are drive gears b All gears on the countershaft are driven gears c The smallest gear on the main shaft 1 Part of first gear 2 Also a fixed gear machined to the shaft d The largest gear on the main shaft is part of the top gear e The largest gear on the counter shaft is part of the first gear f The smallest gear on the counter shaft is part of top gear POWER FLOW ABREVIATIONS M main shaft C counter shaft F fixed gear S slider gear FW Freewheeling gear to Power to opposing gear by Engagement by what slider gear B Direct drive transmissions e SEE FIGURE 6 23 1 Power flow enters on one shaft and leaves on another shaft of the same axis 2 Uses a main drive gear top gear that free wheels on the main shaft 3 Top gear is always 1 1 ratio NOVEMBER 15 16 1999 PAGE 4 4 Direct drive transmissions are more efficient in top gear only 5 Example 4 and 5 speed Harley Davidson transmissions BIG TWIN a The main drive gear is attached to the drive sp
178. st pin offset closer to rear of piston 1 arrow faces forward 2 lug under skirt to left 3 pin closer to rear 6 Mahle piston shape a diamond turned process barrel faced b can retro fit to all 1340cc shovel head engines c things in common with the EVO rings pins clips nly difference is shovel pistons are domed Evo are flat top 7 rings a 3 piece oil control 1340cc Dec 78 and later 1200cc Jan 79 and later b 3 piece oil control set features 1 top ring barrel face 2 2nd ring reverse twist taper face scrapes on the way down twists and hydroplanes on the way up 3 bottom ring 3 piece rails top and bottom expander in the middle less cylinder wall tension than 1 piece ring faster break in i L78 and earlier engines use 1 piece cast iron oil control ring and 2 chrome plated compression rings 4 3 piece set will retro to earlier pistons H Tappet guides 1 4 variations a 66 76 1 2 1 small drain hole countersunk screw holes b 76 1 2 E81 small drain hole straight screw holes c L81 E82 no drain holes had spigot for evacuator d L82 and up 2 transfer holes no spigot 2 inspection a check for cracks base of roller guides b check for wear max 002 between tappet and guide 3 mounting screws a 66 77 1 4 X 24 b 74 84 1 4 X 20 4 updating a drill both drain holes through to the bottom with a 3 32 bit or use 1 8 I Tappets same
179. st rebalance oil restrictor in the pinion shaft no rear cylinder advance mark balance factors used to balance at speed higher balance at higher RPM lower lower RPM balance i 1340 60 ii 1100 69 blue iii 883 62 yellow iv 1200 62 white v after 1989 all 883 flywheels are colored green and all 1200 s are red 1991 and later there s a timing mark on right side flywheel 21 Connecting rods 22 23 24 25 wa wm Na wm a Dog legged 1982 and later ALL Evos b Wrist pin clearance is 2 times that of a B T helps prevent seizure c Bearings i Early 1986 were loose rollers with flat thrust washers ii Late 1986 through current use F A G bearings started on day 095 d For the first 2 months no thrust washers were used added late May i Stepped for clearance wider cage e Service just like the B T bearings i 1 bearing size 3 sizes of crank pin Sprocket Shaft a 5 speed shaft is 0 750 longer than 4 speed i Rotor and stator moved to sprocket shaft from clutch shell ii Rotor pressed and screwed to socket Pinion shaft and race a b c 1986 only unitized caged bearing pressed into case i Race pressed onto shaft 1 185 1 195 from flywheel race ii Grind to size 1 2485 1 249 16rms finish 1987 current uses F A G bearing i 3 pieces 1 outer race pressed into case 2 inner race pressed onto shaft 3 separate bearings ii 4 sizes of
180. stroke does the intake vale open and close e Opens BTDC on the exhaust stroke e Closes ABDC on the compression stroke When and on what stroke does the exhaust valve open and close e Opens BBDC on the power stroke e Closes ATDC on the intake stroke 20 21 22 What is scavenging Removing of exhaust gases from the cylinder Why is it important to time the camshaft with the crankshaft e Valves may contact one another or the piston crown if not timed When does Valve overlap occur e Valve overlap occurs BTDC on the exhaust stroke and ends ATDC on the intake stroke What are some advantages of having valve overlap e Better scavenging e Better power e More cooling e More intake gas air mixture can enter the chamber What are some disadvantages to valve overlap e Emissions e Lower fuel mileage e Loss of Torque and HP in the low and midrange Why is Aluminum a good material to use in the construction of motorcycle engines e Lighter and cools 2 2 5 times better than cast iron What is the function of the squish area of a cylinder head e Increases combustion efficiency e Forces the air fuel mixture into a tighter pocket e Helps mix the air fuel more evenly What is the purpose of the poppet valve e Controls the flow of gases e Transfers heat e Forms seal for combustion chamber Label the parts of this poppet valve A tip B keeper groove C stem D neck weld area E face F margin List the
181. t 2 Components a coil of wire b spring loaded plunger 3 Two Types a Normally open 1 when energized contacts close 2 and energized normally open relay will have 0 resistance b normally closed 1 when energized contacts open 2 an energized normally closed relay will have infinite resistance Mechanical Slide Carburetors 10 11 12 13 14 What circuit flows the smallest amount of fuel give 3 names e Idle e Pilot e Slow The main effect of the idle circuit is from idle to 1 4 throttle When does this circuit flow fuel e All the time What is the purpose of the idle air bleed passage e Aids in atomization Where is the idle air bleed located on the carb e Air cleaner side Is it normal for a carb to have Both air and fuel mixture screws for the idle circuit e No What side of the carb would the air mixture screw be located on e Air cleaner side Turning the air mixture screw clockwise would richen the idle mixture What is the initial air mixture screw setting on most carbs e 1 turns out What side of the carb would the fuel mixture screw be located e Engine side Turning the fuel mixture screw clockwise would lean the idle mixture What should the engine temperature be when adjusting the idle mixture screws e Normal operating temperatures What is the purpose of the idle fuel jet e Meter the amount of fuel flow through the idle circuits The main effect of the idle outle
182. t what is used to meter the fuel during midrange operation e A brass jet or precisely drilled hole Ty What is the purpose of the emulsion tube e Aid in fuel air atomization 8 If the fixed venturi carb has a midrange circuit where is the midrange outlet port located e Air cleaner side of the throttle plate between the by pass outlet ports and the main outlet port 9 In a fixed venturi carb where is the main outlet nozzle located e In the center of the venturi Float Bowl Circuit 10 11 12 13 What is the purpose of the float bowl circuit used in most carbs e To maintain a constant level of fuel in the float bowl at all engine RPMs What carb circuits does the fuel level in the float circuit effect e ALL A high fuel level in the float circuit will cause what type of air fuel mixture e Rich A low level of fuel in the float circuit will cause what type of air fuel mixture e Lean Name 3 float bowl locations in relation to the venturi e Concentric directly underneath e Eccentric off to one side e Remote What is the purpose of the float bowl overflow tube e Prevents fuel from flooding the engine in the event that the float stuck open What does the float push against to control the flow into the float bowl e Float needle To operate properly the float bowl must be vented to the atmosphere How is the level of the fuels and float height changed on adjustable floats e By bending the tang
183. t fork Name 2 types of shift mechanisms e Shift drum e Cam plate What are 2 functions of the shift detent e Help locate the next gear e Help keep the shift mech from moving out of gear Name 3 types of shift detents e Arm and roller e Spring and ball e Spring and plunger What is the purpose of the shift fork e Move the slider gear 26 AR 28 29 30 31 32 33 34 What is the hard plating that can be found on shift forks e Hard or flash chrome One shift fork can be used for selecting a maximum of two gear ratios A 5 speed transmission will normally use 3 shift forks What are 3 types of damage we should look for when inspecting shift forks e Bent e Broken e Burnt over heated For a transmission to operate properly it should e Be vented e Lubricated e And sealed around the shaft What is the purpose of the dual range transmission e Normally a2 speed allows for a lower and high range What is the purpose of the final drive e Transmit power from the transmission to the rear wheel What are the 3 types of motorcycle final drives e Chain e Belt e Shaft What is the name of the fluid found in most shaft drives e Hypoid gear oil Venturi Effect and Design 1 What is the venturi effect based on Bernoulli s principles e Ina tub as velocity increases relative pressure decreases De What is a definition of relative pressure e The force pushing on an object
184. t in the 3 jet e Idle to 1 4 throttle Where is the idle outlet port located on a 3 jet carb e Engine side of the throttle plate or slide Where is the by pass port located e Air cleaner side of the throttle plate or slide At what opening does the primary main jet have its main effect e to throttle What is the purpose of the cold start device e To provide an excessively rich mixture Why is a cold start device necessary e Fuel doesn t atomize well in cold environments Name 3 types of cold start devices e Choke e Enrichener e Tickler How does the choke type cold start device operate e Restricts air flow What side of the carb is the choke plate located e Air cleaner side How does the enrichener type cold start device work 14 15 16 17 18 19 20 21 22 23 24 25 26 2T e Opens a separate circuit that s designed to provide a rich mixture What should the throttle position be for proper operation of the enrichener e Closed Where is the enrichener outlet port located in the mechanical slide carb e Engine side of the slide What feature of fuel injection ensures good fuel atomization e The tiny holes in the injectors What single part takes the physical place of the carb in a fuel injection system e Throttle body In a fuel injection system what is the ECM e Electronic control module Name 3 types of auxiliary devices found on carbs e Accelerator
185. t on piston for 883 and 1100 install either direction c late 1989 to present 883 and 1200 pistons have offset with the arrow on piston crown facing forward d As of October 1994 883 pistons are coated with Teflon for break in Piston pin a 883 is shorter than 1100 or 1200 diameter is the same b 1200 same 1340 but are NOT interchangeable c 1200 have either 12 or a V grove stamped on the edge Tappets a XL same as B T b No restrictor on Early 1986 c Ristrictor added Late 1986 1990 i Reduces oil to the top end ii Helps keep lifter filled at highway speeds hydraulic lifters as opposed to solid d Tappet working ranges Tappet block 4 speed a Toremove from case turn tappet block and lift from case b Tappet to block fit i 0 0008 to 0 0023 ii 0 003 service wear iii there are no stock oversizes available c new o rings are made from silicone rubber and will swell when exposed to oil d oil leaks i tappet block to case oil will be grungy ii small o ring to case oil will be dirt free possible that the counterbore is to deep in the case should be 0 050 0 060 iii shim up with a small washer iv use Hylomar to seal e Torque to 15 18 ft lbs Gearcase cover a Bolt torque patterns given in Tech Tips 25 b 2 dowel pins are for centering cover c computerized sizes for gear fitment i quadrex room temp of 68 degrees ii measures center to center of bushings down to 0 00
186. t port is e It flows fuel at idle 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 Where is the idle outlet port located on mechanical slide carbs e Engine side of slide The main effect of the by pass port is e Aids transition to mid range by allowing a little more fuel just off idle How is the slide controlled in a mechanical slide carb e By the riders input on the throttle directly What is the purpose of the slide e Vary the size of the venturi Name 3 shapes of slides e Round e Flat e Radial flat What is the purpose of the slide cut away e Aids in transition from idle to mid range The slide cutaway should face the air cleaner side of the carb A slide cutaway of 1 0 will have a rich mixture and a slide cutaway of 3 5 will have a lean mixture The main effect of the midrange fuel circuit is from to 3 4 throttle The jet needle is attached to and moves with the slide The needle jet is stationary in the body of the carb On adjustable type jet needles non EPA the lowest clip position closest to the taper will result in the richest midrange mixture and the highest clip position furthest from the taper will result in the leanest midrange mixture 3 types of needle jets are e Bleed e Primary e Primary bleed The main effect of the main fuel high speed circuit is from 34 to WOT throttle Where is the main jet located e In series with the
187. ter flow END OF FOUR STROKE ENGINE CYLINDER HEADS AND VALVES NOTES THEORY NOTES SUBJECT Four stroke engine cylinders pistons and piston rings KEY POINTS 1 Cylinders textbook pages 50 55 A Purposes 1 Guide piston travel 2 Thrust surface for the piston skirt 3 Aids in heat transfer B Air or liquid cooled C Types 1 Cast iron a Advantages 1 All one piece 2 Boreable 3 Cheap to manufacture b Disadvantages 1 Poor heat transfer compared to aluminum 2 Too heavy 2 Aluminum with cast iron or steel sleeve a Advantages 1 Better heat transfer when compared to cast iron 2 Boreable NOVEMBER 2 3 1999 PAGE 2 3 Lighter in weight compared to cast iron b Can have replaceable or non replaceable sleeves c Disadvantages 1 Heavier than plated aluminum cylinders 2 Poorer heat transfer than plated aluminum cylinders 3 Plated aluminum cylinders also called Nikasil or composite cylinders a Advantages 1 Best heat transfer 2 Lightest in weight 3 Longest lasting when properly maintained b Disadvantages 1 Non boreable 2 Replace only D Cross hatch e SEE FIGURE 4 42 1 Minute scratches are purposely installed into the cylinder wall 2 Honing creates the crosshatch pattern 3 Purposes a Help seat the piston rings b Retain oil on the cylinder walls 4 Cross hatch angle should be approximately 45 60 degrees E Cylinder wear 1 Cylinders must be round and true they cannot ha
188. ter pump inlet and discharges it into the engine s water jacket 3 It feeds coolant uniformly to the cylinder and cylinder head water jackets 4 Basic parts pump may or may not be rebuildable la Shaft 1b Impeller NOVEMBER 17 1999 PAGE 3 lc Bearing s ld Mechanical seal and oil seal le Housing 1f Drain hole tell tale hole 5 If coolant is leaking out of the drain hole then the mechanical seal is leaking If engine oil is leaking out of the drain hole then the oil seal is leaking b Radiator 1 Heat exchanger 2 Usually not a dealer repair item because they are usually aluminum c Thermostat 1 Temperature sensitive flow valve 2 Purpose la Allows for a quicker engine warm up time 1b Allows to operate at pre determined temperatures 3 When the engine is first started the thermostat is closed allowing coolant to flow through the radiator d Radiator cap 1 Purposes la Seals the cooling system 1b Determines the cooling system s operating pressure lc Raises the boiling point by 3 degrees Fahrenheit for every 1 PSI 2 Test to be sure that the cap holds specified pressure for a required time la See service manual for specifications lb If the cap fails the test replace it 3 Motorcycle radiator caps usually operates at 12 14 PSI NOVEMBER 17 1999 PAGE 4 e Coolant 1 Usually a 50 50 mixture of distilled water and anti freeze ethylene or propylene glycol 2 Use coolant recommended
189. th a soft coating 3 Purposes a Supports axial loads b Reduces shaft end play c Proper spacing especially for gears Bushings 1 The cylindrical lining is made of soft alloy such as silicone bronze aluminum brass plastic and etc 2 Most are a pressed fit into place and are replaceable 3 Purposes Support radial and sometimes axial loads 4 Main advantage High load ability due to the amount of surface area END OF FRICTION REDUCING DEVICES NOTES NOVEMBER 18 1999 THEORY NOTES SUBJECT Fuels KEY POINTS 1 The purpose of fuels A Gives satisfactory engine performance over a wide range of circumstances 2 Octane rating A Octane rating The measurement of a fuel s ability to resist detonation 1 2 3 Known as knock rating The higher the octane the higher the fuel s resistance to detonation There is no advantage in using gasoline of higher rating than the engine needs to operate detonation free B Factors that can influence the octane rating needs of an engine 1 2 3 4 5 6 7 Air temperature The higher the temperatures the better chance of detonation Altitude The lower the altitudes the better chance of detonation Humidity The lower the humidity the better chance of detonation Ignition timing The more advanced ignition timing the better the chance of detonation Carburetor jetting The leaner the air fuel mixtures the better chance of detonation
190. that flows fuel at an idle 100 of the time 2 Located on the engine side of the throttle plate e By pass ports also called transfer ports 1 Aids in smooth transition by allowing alittle more fuel flow just off idle 2 Will have 1 to 4 ports to aid in smooth transition to throttle 3 Located on the air filter side of the throttle plate B Mid range circuit also called intermediate circuit 1 Operation Main effect 4 throttle opening to throttle opening 2 Parts a Needle jet 1 Stationary 2 The larger the number the richer the entire range b Jet needle 1 Taper varies the amount of fuel flow through the needle jet 2 In series with the main jet c Main jet air bleed passage 1 Needle jet and jet needle circuit shares the air bleed passage with the main jet circuit 2 Purpose Aids in atomization of fuel C Main jet circuit also called high speed circuit 1 Operation Main effect 34 throttle opening to full throttle opening NOVEMBER 22 23 1999 PAGE 3 2 Parts a Main fuel jet 1 Located in series with the needle jet and the jet needle 2 After throttle to full throttle the main jet is unrestricted b Air bleed passage or jet c Air bleed tube END OF CONSTANT VELOCITY CARBURETOR NOTES NOVEMBER 17 1999 THEORY NOTES SUBJECT Cooling systems KEY POINTS 1 Purposes A Rids the engine of unwanted heat B Allows the engine to operate at a pre determined temperature 2 Three types of
191. the fuel in the float bowl affects all carburetor circuits A Fuel level The level of fuel in the float bowl as compared to a reference mark 1 High fuel levels result in a rich mixture 2 Low fuel levels result in a lean mixture NOVEMBER 22 1999 PAGE 3 B Float height The distance from the carburetor body to the outer edge of the float with the float needle closed 1 Measured with the carburetor off of the motorcycle and laid on its side a High float heights result in lean mixtures b Low float heights result in rich mixtures 4 Adjusting the fuel volume in the float bowl A Most manufacturers provide fuel level or float height specifications B Most floats have a float tang that can be bent to adjust the float height C Float height controls the point at which the float needle will close D On some EPA carburetors the float tang is non adjustable 5 Variation to the float bowl diaphram type carburetors A Uses a vacuum type pump instead of a float bowl B Main advantage Can operate at any angle C Normally uses three hoses 1 One hose is used for fuel delivery from the fuel tank 2 One hose is used to return unused fuel to the fuel tank 3 One hose is used for a vacuum hose from the intake manifold to the fuel pump on the carburetor END OF FLOAT BOWL CIRCUIT NOTES NOVEMBER 3 1999 THEORY NOTES SUBJECT Four stroke engines crankshafts and connecting rod KEY POINTS 1 Connecting rods textbook pages 57 60
192. the main journal of approximately 0 001of an inch d Main bearings support main journals which prevents journal from touching the labyrinth seal e When the engine is running the labyrinth area fills with fluid which forms a seal 7 Crankcases A Contains NOVEMBER 8 9 1999 PAGE 5 1 Crankshaft and primary drives 2 Sometimes one or more of the following a Oil pump b Primary shaft c Main shaft d Countershaft B Types 1 Vertical or horizontal split C Two stroke crankcases must be sealed from the atmosphere and the transmission area 1 Gasket or sealant may be used to seal the crankcase halves and the transmission area 2 Seals used to seal the ends of the crankshaft a Primary drive seal wet side 1 Located on the clutch side of the engine normally located behind the main bearing 2 Symptoms if the seal leaks la Engine will smoke excessively lb Engine will have poor low end performance lc Possibly foul the spark plug b Timing side seal dry side 1 Located on the electrical side of the crankshaft usually located before the main bearing 2 If this seal leaks the symptoms are la Engine will run lean 1b Engine will overheat which could lead to piston to cylinder seizure lc Wet on timing side possible wet ignition points if model has points 3 Two stroke pressure leak down testing using a two stroke leak down vacuum tester NOVEMBER 8 9 1999 PAGE 6 a Method 1 Place the piston at BDC
193. the opening and closing of e The intake port Piston skirt e The transfer ports Piston crown e The exhaust port Piston crown List the 6 events of 2 stroke engine operation Intake Compression Timed ignition Power Exhaust Transfer When does scavenging occur on the 2 stroke engine e On the downstroke of the piston when the exhaust port is open and the transfer ports open to help push the exhaust gases out 10 11 12 13 14 15 16 17 18 19 What is the purpose of loop scavenging e Helps the fresh charge loop through the secondary area pushing out more of the spent charge cooling the chamber and allowing for more complete intake charge What is the expansion chamber e Tuned chamber exhaust that operates off sonic waves Name 4 purposes of the expansion chamber e Assist scavenging e Assist transfer event e Adjusting charge loss e Adjusting power band characteristics When does the intake port piston port e Open BTDC e Close ATDC When does the Transfer port e Open BBDC e Close ABDC When does the exhaust port e Open BBDC can be ATDC if over 180degrees e Close ABDC can be BTDC if over 180degrees The 6 events occur in how many strokes of the piston e 2 strokes The 6 events occur in how many revolutions of the crankshaft e revolution Where does primary compression take place e In the crankcase below the piston crown
194. tion timing is set valve train adjustment air filter service and spark plug inspection B Motorcycle must be at operating temperature C Proceedure check manual for initial settings Bendix 72 73 XL and FL FX 1 1 2 turns out Keihin 2 turns out 1 set idle speed to 900 to 1100 RPM left side carb 2 slowly turn mixture screw clockwise to lean out 3 when rear cylinder firing faulters stop turning screw 4 turn screw counter clockwise 1 8 1 4 turn until rear cylinder fires approxamately 75 90 of the time 5 adjust idle speed as necessary IDLE MIXTURE SCREW stock set up 2 turns 1 1 2 turns 1 turn more than this normal less than this jetis too small initial setting jet is too big 3 Fast idle Keihin adjust only with engine cold A Adjust idle for 1500 RPM when choke is in 2 position right side of carb B Misadjustment 1 too little no fast idle 2 too much overrides slow idle adjustment engine races 4 Choke cable adjustment provides full open full closed settings A Keihin carbs provide spring tension adjustment if spring is weak choke plate will open when cranking engine to start will cause a lean mixture 5 Air leak problems A Symptoms 1 erratic idle 2 spit back through carb 3 hesitation surging 4 poor performance detonation 5 slow return to idle 6 Air leak diagnosis A Using contact cleaner spary around manifold area throttle shaft B Air leaks produce a change in idle speed
195. tment whine d gear tooth changes cam pinion breather 1 E77 and earlier straight tooth profile 2 L77 and later curved tooth profile machined ring on side of gear i 7 gear sizes identified by color codes 3 never mix old and new style cam breather or pinion parts 4 Cam types a H cam E83 and earlier S cam L83 and 84 b S cam all parts and accessories less duration than H cam more mid range quiter valve train softer 5 Gear inspection a lobes discoloration and pits b bearing surfaces change from INA to Torrington c teeth d dog ear washer installed eats down slant towards rear G 58 72 One shot oiling system 72 and up flat side bushing that lines up oil holes in the bushing with oil passage constant oiling L Solid lifter usage 1 can ruin hydraulic type cam it has no expansion ramp 2 solid ype lifter cams need expansion clearance ramps to reduce shock on cam lobes tappet rollers and valve stems 3 solid lifters provide more cam lift than hydraulic lifters M Breather gear 1 66 E77 steel straight tooth small nipple end 2 L77 E81 steel curved tooth large nipple end 3 L81 and up Zytel plastic curved tooth uses 6 slot window N Pinion and oil pump gear 1 pinion 58 E77 full tooth gear with straight profile L77 84 half tooth gear with curved profile color coded availability 2 inspection
196. to deliver current 1 fora period of time before it reaches a state of discharge 2 12v battery state of discharge is 10 5v B Time period for motorcycle batteries 1 usually 10 hours 2 14 ampere hour batter before reaching a state of discharge a delivers 1 4 amps for 10 hours b delivers 14 amps for 1 hours c delivers 1 amp for 14 hours 8 Effect of temperature on batteries A Inactive batteries discharge 1 Conventional batteries 5 to 1 daily at an atmospheric temp of 77degrees F 2 Low maintenance MF 15 to 3 daily at an atmospheric temp of 77degrees F B Cold slows down the chemical action and causes a slower discharge rate C Heat and humidity speed the chemical action and causes a higher rate of discharge D When not being used store batteries in a cool dry place 9 Factors affecting battery performance A Anything that increases the motors resistance to turning or starting 1 Poor engine tune cold oil worn starter 2 Example a 1000watt starter 13 5v available a at 13 5v amps required 74 1000 13 5 74 b as the starters load increases available voltage drops making demand for amps increase at 11V amps required 91 1000 11 91 c Result batteries capacity ampere hour rating fixed but current requirement increased battery drains sooner B Battery s state of charge a low battery has less cranking power than a charged one C Water level in each cell without sufficient electrolyte the battery can t efficie
197. trol 3 Example if a horn circuit develops an unwanted ground before the switch the horn will activate continuously C Short circuit 1 Circuit that has a path for current to flow back to the source Before the load device 2 Takes the resistance out of the circuit 3 Symptoms a Blown fuse b Excessive heat and damage to wiring harness and or other components Particularly if a circuit doesn t use a protection device 6 Voltage Drop A The amount of voltage used between two points B If there s more that one load in a circuit part of the voltage will drop across each load C Purpose of measuring voltage drop 1 Helps in troubleshooting by locating unwanted resistance 2 More accurate than a resistance test D Sum of all individual voltage drops will equal the applied source voltage Electrical Terminology 1 Electricity A The flow of electrons through a conductor 2 Atom smallest part of whole matter A The basic parts 1 Proton a Positively charged particle b Found in the nucleus 2 Neutron a Particle that has NO charge b Found in the nucleus c Neutrons add weight and occupy space 3 Electron a Negatively charged particle b Orbits the nucleus c Orbit is called a shell i Outermost shell is called the Valence Shell ii electrons in the valence shell are valence electrons iii Valence electrons my be enticed to leave the shell 3 Electromotive Force EMF A Electrical pressure 1 a 2 3 5
198. unded retard power 1 2 wide open low open off ungrounded D E Magnavox rotors silver 80 83 stage I gold 83 and up stage II Rotor cup 1 window closed sensor ground 0 VDC at green wire 2 window open sensor not grounded power supplied to red wire up to 4 5 5 5 VDC 90 and up 1OVDC 3 rotor spins at half engine speed Ignition coils collapsing field 1 63 79 points coil low output 17 KV 2 80 83 electronis coil higher output 22 KV 3 84 and up mailbox style 28 KV 4 screamin eagle 39 KV 5 check for voltage at input and output of coil a primary must be 9 6 vdc minimum Rev limiters 1 X1 models 5400 RPM 2 big twin 5200 RPM 3 screamin eagle 8000 RPM CHARGING SYSTEM 1 Components A B C D Battery Stator Rotor Regulator 2 Quick test of charging system A B Use meter across batteryon bike not running check VDC Recheck with bike running voltage should increase 13 5 15 vdc this is not conclusive 3 Stator coil of wire GAw gt tech 2 To check stator disconnect regulator set meter to ohms and check lead to lead Should have resistance check manual for specs Check for grounds lead on stator to ground should read OL check both leads Ac voltage output checks checks the rotor 1 set meter to vac and place leads pin to pin 2 run bike at idle and read meter 3 run bike at 2000 RPM and read meter reading should be double
199. unterweights e SEE FIGURE 4 50 a Ona separate shaft b Chain or gear driven c Shafts must be timed properly with the crankshaft F Types of crankshafts 1 One piece a Cast or forged as one piece b Strongest in design c Must be used with a multi piece connecting rod NOVEMBER 3 1999 g PAGE 3 Most are cross drilled for oil delivery to the connecting rod journals Most use plain bearings at the main and connecting rod journals Most use both high oil volume and pressure to the bearings Not rebuildable 2 Multi Piece g Halves are cast or forged The connecting rod journal is a press fit or bolted to the halves Most are rebuildable Most use a one piece connecting rod Most use roller bearings at the connecting rod journal Most use ball bearings on the main journals All must be trued after re assembly G Multi cylinder crankshafts Use different offset positions for each cylinder depending on design 1 360 degree design a b c 2 3 a Both pistons move together Requires more counter weighting Vibrates at higher RPM s 180 degree design Pistons move in opposite directions Requires less counter weighting Less vibration at higher RPM s If used on an in line four cylinder engines a pair of 180 degrees crankshafts are used 120 degree design Used on 3 and 6 cylinder engines NOVEMBER 3 1999 PAGE 4 b Piston movement is 120 degrees apart c 6cylinder engines use a
200. ut attracting contaminants Physical Laws and Combustion Homework 1 10 11 12 13 14 What are six characteristics of a liquid Has no definite shape Conforms to the shape of the container Can transmit pressure Will NOT expand to fill a container Heavy for equal volume of gas Non compressible What is the definition for atomization e Liquid drops suspended in air What is the definition for vaporization e Liquid converted to gaseous state What is the definition of viscosity e Measurement of a fluids resistance to flow Define Viscosity Index e The number that indicates the Viscosity Constancy of a fluid at a controlled temperature and pressure Can air a gas be compressed e Yes What is the atmospheric pressure at sea level e 14 7PSI How does altitude affect atmospheric pressure and density e Pressure and Density decrease What is air composed of e 78 Nitrogen e 21 Oxygen e 1 Inert gases What is the definition of Air Density e Amount of Oxygen particles per given volume What does Boyles Law explain to us about gases e The more gas is compressed the more heat and pressure e Also that if a given volume of gas is halved it s pressure is doubled and vise versa What normally happens to material when it s heated e It expands What normally happens to material when it is cooled e It contracts What is the reason for atmospheric pressure movement into an eng
201. ve any taper or out of roundness 2 Measure axis points three X and three Y dimensions NOVEMBER 2 3 1999 PAGE 3 3 Measure at least 6 places to check out of round and taper See manufacturer s specifications 2 Pistons e SEE FIGURE 4 35 A Purposes 1 Transfer power to the connecting rod 2 Aid in sealing the combustion chamber 3 Thrust and sealing surface for the piston rings B Manufacturing design 1 Directional Must be installed as specified in the service manual 2 Tapered 3 Top crown has a smaller diameter than bottom skirt a Allows for different heat expansion of crown and skirt 4 When cold crown has smaller diameter than skirt but crown expands more than skirt 5 Cam ground a Ground to an oval shape piston has smaller radius at wrist pin axis b Allows for wrist pin boss expansion thicker piston material expands more c When piston reaches operating temperatures piston is round C Common manufacturing methods 1 Cast most common 2 Forged a Aluminum alloy ignot is forced into a die under extreme pressure b More dense and stronger c May require more clearance due to expansion rate always check manufacturer s specifications D Parts of a piston NOVEMBER 2 3 1999 PAGE 4 1 Crown a Top of the piston and the floor of the combustion chamber b Hottest part of the piston due to combustion chamber temperatures c Crown area will expand more than rest of piston because it is
202. ve the decimal point the same number of places in the same direction 6 Converting inches to millimeters A 1inch 25 4 mm B Method multiply inches X 25 4 1 Example a 3 025 inches X 25 4 76 835 mm 7 Converting inches to centimeters A 1inch 2 54 cm B Method multiply inches X 2 54 1 Example a 3 025 inches X 2 54 7 6835 8 Converting millimeters to inches A Imm 0 03937 inches B Method multiply mm x 0 03937 inches 1 Example a 76 84 mm X 0 03937 3 025 inches 9 Converting Kilogram Centimeters2 to pounds per square inch A 1 Kilogram Centimeters2 14 224 pounds per square inch PSI B Method multiply kilogram centimeters2 X 14 224 PSI 1 13 kg cm2 184 912 PSI 10 Converting centimeters to inches NOVEMBER 4 1999 PAGE 3 A 1cm 0 3937 inches B Method multiply cm X 0 3937 inches 1 Example a 7 684 cm X 0 3937 3 025 inches 11 Converting kilogram meters to foot pounds A 1 kilogram meter 7 233 foot pounds B Method multiply kilogram meters X 7 233 foot pounds 1 5kg m 36 165 ft lb END OF METRIC SYSTEM NOTES OCTOBER 27 1999 THEORY NOTES SUBJECT Physical Laws KEY POINTS 1 MATTER Reference MMI textbook Chapter 3 A Material substance that occupies space and weight B Cannot be created or destroyed C Can be changed from one form to another by chemical or physical means D EXAMPLE 1 Changes in water from ice to water to steam 2 Three forms of matter
203. vided by 0 375 1 42 so rocker arm ratio 1 42 1 d Disadvantages of rocker arms 1 Creates side loads on valve stems and guides 2 Side loads cause excessive wear in that area 2 Shims and buckets e SEE FIGURE 4 30 a Bucket is located above the valve in a pocket located in the cylinder head b Shim location top of or underneath a bucket c Changing shim sizes adjusts valve clearance d Advantages Does not create side loads 5 Valve clearance lash adjusters A Purpose of clearance is to allow for 1 Heat expansion 2 Oil clearance 3 Proper sealing and timing 4 Too little clearance will cause a Valve not to seal properly b Insufficient heat transfer when the engine is at operating temperatures 5 Too much clearance will cause a Excessive wear b Excessive noise NOVEMBER 1 2 1999 PAGE 6 c Reduced volumetric efficiency 6 Valve clearance checking and adjusting must be done with the engine at ambient temperatures 7 Types e Screw and lock nut e Shim and bucket e Bucket e Hydraulic e Shim e Eccentric a Screw and lock nut 1 Screw can be turned in or out to change the clearance 2 Lock nut is used to hold the screw in place 3 Three common screw and lock nut locations la Rocker arm 1b Push rod lc Lifter b Shim and bucket 1 Used as a valve open closing device and an adjustment device 2 Clearance adjusted by changing shims 3 Shims come in various sizes usually in increment
204. wheel and final drive housing 3 Check the condition of the U joint 4 Most use hypoid gear oil in the final drive housing END OF FINAL DRIVE NOTES NOVEMBER 23 1999 THEORY NOTES SUBJECT Fixed venturi carburetors e SEE FIGURE 8 22 KEY POINTS 1 Key features A Venturi size is fixed has no slide to change the venturi size during operation B The throttle plate controls the amount of air entering the engine 1 Rider controlled 2 Located on the engine side of the venturi C Most have accelerator pumps to aid in transitions 2 Circuits A Idle circuit also called a slow speed pilot or an idle and transfer circuit 1 Operation Main effect Idle to about throttle opening 2 Parts a Idle fuel jet Meters the amount of fuel flow may be metered through a main jet first b Idle air bleed 1 Aids in atomization by mixing air with fuel 2 Some air bleed passages may use a removable air jet c Mixture screws air or fuel usually fuel 1 Idle outlet port la The only port that flows fuel when the throttle valve is closed 1b Located on the engine side of the throttle plate d By pass ports also called transfer ports NOVEMBER 23 1999 PAGE 2 1 Aid in smooth transition by allowing a little more fuel flow just off idle 2 Located on the air filter side of the throttle plate e Other parts are sometimes used to aid in transition between circuits particularly idle and mid range circuits 1 Accele
205. ximately 15 to 25 5 To realize an increase of horsepower the following must be done to the engine a Advance the ignition timing b Increase the compression ratio c Increase the carburetor jet size approximately 2 18 times 6 Disadvantages a Its harmful to the body b Its harmful to the engine components c Its hydroscopic absorbs water d Its harmful to rubber cork and plastic fuel system components END OF FUEL NOTES NOVEMBER 9 10 1999 THEORY NOTES SUBJECT GEAR IDENTIFICATION AND RATIOS KEY POINTS 1 Gears rotating levers e SEE FIGURE 6 1 AND 6 2 Larger the gears radius distance from center the greater the leverage Force behind a moving gear is torque force X distance from the pivot point Speed measured in revolutions per minute RPM Continuous force One tooth of the drive gear lever is always pushing on a tooth of the driven gear 2 Purposes of gears A B C D E To transmit power To change direction of rotation To increase torque which results in a decrease in RPM like transmission low gears To increase RPM s which results in a decrease in torque like transmission high gears Timing an example is a gear driven cam shaft 3 Types of gears are A Spur gear e SEE FIGURE 6 1 Off set spur gear Helical gear e SEE FIGURE 6 1 Internal gear Worm gear NOVEMBER 9 10 1999 PAGE 2 F Idler gear G Bevel gear H Ring gear I Se
206. y Direction of current flow Derived from the word Pole Direct Current DC Current that flows in one direction only Example Battery current is DC DC flow theories Conventional Oldest and most accepted in the motor vehicle trades Idea that current flows from positive to negative From battery positive terminal through circuits and back to battery negative terminal Theory used by MMI Electron Theory Used mostly by electronic technicians Idea that current flows from the negative to the positive 13 Alternating current AC A B C 1 2 3 Current whose polarity alternates i e flows one way then the other Motorcycle charging systems generate AC Induction Magnetic field Conductor coil of wire Motion of conductor OR magnetic field Fixed Venturi Carburetors 1 Name 2 main differences in fixed venture carbs as compared to variable venturi carbs e Fixed venturi e Throttle plate regulates airflow 2 What controls the airflow in a fixed venturi carb e Throttle plate 3 Where is the idle outlet port located on a fixed venturi carb e Engine side of the throttle plate 4 Where are the by pass ports located on a fixed venturi carb e Air cleaner side of the throttle plate 5 In a fixed venturi carb used on a street motorcycle what 3 things will aid in transition from idle to mid range e By pass ports e Accelerator pump e mid range ports 6 If the fixed venturi carb has a mid range circui

2-Stroke Cylinders to Crankshafts - Motorcycle Mechanics Institute

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