Always turn off the engine Congratulations on your purchase of damage to the machine. while refueling. Take care to a Yamaha YZ series. This model is not spill any gasoline on the the culmination of Yamaha's vast ex- engine or exhaust system.
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Yamaha dealer. repair, assembly, and inspection op- erations. This manual should be considered a In this revised format, the condition of...
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der of the jobs in the exploded di- 4. A job instruction chart "4" accom- HOW TO READ DESCRIPTIONS agram. A number that is enclosed panies the exploded diagram, To help identify parts and clarify pro- by a circle indicates a disassem- providing the order of jobs, names cedure steps, there are exploded dia- bly step.
DESCRIPTION GENERAL INFORMATION DESCRIPTION Clutch lever 11. Coolant drain bolt Hot starter lever 12. Rear brake pedal Front brake lever 13. Valve joint Throttle grip 14. Fuel cock Radiator cap 15. Cold starter knob Fuel tank cap 16. Drive chain Engine stop switch 17.
1. Remove all dirt, mud, dust, and 1. When ordering parts, you can foreign material before removal give the number to your Yamaha and disassembly. dealer for positive identification of • When washing the machine with the model you own.
• Connector 5. Keep away from fire. ALL REPLACEMENT PARTS The two connectors "click" together. 1. We recommend to use Yamaha 7. Check for continuity with a tester. genuine parts for all replace- ments. Use oil and/or grease rec- • If there in no continuity, clean the...
SPECIAL TOOLS SPECIAL TOOLS The proper special tools are necessary for complete and accurate tune-up and assembly. Using the correct special tool will help prevent damage caused by the use of improper tools or improvised techniques. The shape and part number used for the special tool differ by country, so two types are provided.
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SPECIAL TOOLS Tool name/Part number How to use Illustration Steering nut wrench This tool is used when tighten the YU-33975, 90890-01403 steering ring nut to specification. Cap bolt wrench This tool is used to loosen or tighten YM-01500, 90890-01500 the base valve. Cap bolt ring wrench This tool is used to loosen or tighten YM-01501, 90890-01501...
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SPECIAL TOOLS Tool name/Part number How to use Illustration Clutch holding tool This tool is used to hold the clutch YM-91042, 90890-04086 when removing or installing the clutch boss securing nut. Valve guide remover This tool is needed to remove and Intake 4.5 mm (0.18 in) install the valve guide.
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SPECIAL TOOLS Tool name/Part number How to use Illustration Digital tachometer This tool is needed for observing en- YU-39951-B, 90890-06760 gine rpm. YAMAHA Bond No. 1215 (ThreeB- This sealant (Bond) is used for ® No. 1215) crankcase mating surface, etc. 90890-85505...
CONTROL FUNCTIONS CONTROL FUNCTIONS ENGINE STOP SWITCH The engine stop switch "1" is located on the left handlebar. Continue push- ing the engine stop switch till the en- gine comes to a stop. THROTTLE GRIP COLD STARTER KNOB The throttle grip "1" is located on the When cold, the engine requires a right handlebar;...
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STARTING AND BREAK-IN 6. Return the cold starter knob to its The engine fails to start original position and run the en- Pull the hot starter lever all the way If knocking or pinging occurs, use a gine at 3,000–5,000 r/min for 1 or out and while holding the lever, kick different brand of gasoline or higher 2 minutes.
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STARTING AND BREAK-IN the engine stop switch. Then, re- start the engine and check its op- eration within no more than 5 minutes after it is restarted. 4. Operate the machine in the lower gears at moderate throttle open- ings for five to eight minutes. 5.
TORQUE-CHECK POINTS TORQUE-CHECK POINTS Frame construction Frame to rear frame Combined seat and fuel tank Fuel tank to frame Exhaust system Silencer to rear frame Engine mounting Frame to engine Engine bracket to engine Engine bracket to frame Steering Steering stem to handlebar Steering stem to frame Steering stem to upper bracket Upper bracket to handlebar...
CLEANING AND STORAGE CLEANING AND STORAGE the carburetor float bowl. 2. Remove the spark plug, pour a ta- CLEANING blespoon of SAE 10W-30 motor Frequent cleaning of your machine oil in the spark plug hole, and re- will enhance its appearance, maintain install the plug.
GENERAL SPECIFICATIONS SPECIFICATIONS GENERAL SPECIFICATIONS Model name: YZ450FX (USA, CDN, AUS, NZ) YZ450F (EUROPE, ZA) Model code number: 2S2B (USA,CDN) 2S2C (EUROPE) 2S2E (AUS, NZ, ZA) Dimensions: USA, CDN, AUS, NZ, ZA EUROPE Overall length 2,194 mm (86.38 in) 2,195 mm (86.42 in) ←...
GENERAL SPECIFICATIONS Fuel: Type Premium unleaded gasoline only with a research octane number of 95 or higher. Tank capacity 7.0 L (1.54 Imp gal, 1.85 US gal) Carburetor: Type FCR-MX39 Manufacturer KEIHIN Spark plug: Type/manufacturer CR8E/NGK (resistance type) 0.7–0.8 mm (0.028–0.031 in) Clutch type: Wet, multiple-disc Transmission:...
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MAINTENANCE SPECIFICATIONS Item Standard Limit Stem-to-guide clearance (IN) 0.010–0.037 mm (0.0004–0.0015 in) 0.08 mm (0.003 Stem-to-guide clearance (EX) 0.020–0.047 mm (0.0008–0.0019 in) 0.10 mm (0.004 Stem runout limit ---- 0.01 mm (0.0004 in) Valve seat width (IN) 0.9–1.1 mm (0.0354–0.0433 in) 1.6 mm (0.0630 Valve seat width (EX) 0.9–1.1 mm (0.0354–0.0433 in)
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MAINTENANCE SPECIFICATIONS Item Standard Limit Piston off-set 1 mm (0.0394 in) ---- Piston pin bore inside diameter 18.004–18.015 mm (0.7088–0.7093 in) 18.045 mm (0.7104 in) Piston pin outside diameter 17.991–18.000 mm (0.7083–0.7087 in) 17.971 mm (0.7075 in) Piston rings: Top ring: Type Barrel ----...
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MAINTENANCE SPECIFICATIONS Item Standard Limit Air filter oil grade: Foam-air-filter oil or equivalent oil ---- Clutch: Friction plate thickness 2.92–3.08 mm (0.115–0.121 in) 2.8 mm (0.110 Quantity ---- Clutch plate thickness 1.5–1.7 mm (0.059–0.067 in) ---- Quantity ---- Warp limit ---- 0.1 mm (0.004 Clutch spring free length...
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MAINTENANCE SPECIFICATIONS Item Standard Limit Side clearance 0.09–0.17 mm (0.0035–0.0067 in) 0.24 mm (0.009 Housing and rotor clearance 0.03–0.10 mm (0.0012–0.0039 in) 0.17 mm (0.007 Bypass valve setting pressure 40–80 kPa (0.4–0.8 kg/cm , 5.69–11.38 ---- psi) Cooling: Radiator core size Width 120.2 mm (4.73 in) ----...
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MAINTENANCE SPECIFICATIONS Item Standard Limit ← Optional spring ---- ← Enclosed gas pressure 1,000 kPa (10 kg/cm ---- 142 psi) Swingarm: Swingarm free play limit ---- 1.0 mm (0.04 Wheel: Front wheel type Spoke wheel ---- Rear wheel type Spoke wheel ---- Front rim size/material 21 ×...
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TIGHTENING TORQUES Tightening torque Part to be tightened Thread size Q'ty m•kg ft•lb △ Front wheel axle and axle nut M16 × 1.5 10.5 △ Front wheel axle holder M8 × 1.25 △ Front brake disc and wheel hub M6 × 1.0 △...
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TIGHTENING TORQUES Tightening torque Part to be tightened Thread size Q'ty m•kg ft•lb Fuel tank and seat set bracket M6 × 1.0 Fuel tank and fuel tank bracket M6 × 1.0 Seat M8 × 1.25 △ Side cover M6 × 1.0 △...
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TIGHTENING TORQUES GENERAL TORQUE TORQUE SPECIFI- SPECIFICATIONS CATION (Bolt This chart specifies torque for stan- (Nut) dard fasteners with standard I.S.O. m•kg ft•lb pitch threads. Torque specifications 6 mm for special components or assem- blies are included in the applicable sections of this book.
CABLE ROUTING DIAGRAM CABLE ROUTING DIAGRAM Fuel tank breather hose 10. Hot starter cable Pass the cylinder head breather Radiator hose 1 11. Carburetor breather hose hose on the outside of the radia- Cylinder head breather hose 12. Carburetor overflow hose tor hose 1 and between the radi- Hose holder Insert the end of the fuel tank...
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CABLE ROUTING DIAGRAM Pass the clutch cable in front of the radiator mounting boss. Install the connector cover so that it does not come in between the radiator hose 1 and radiator. Pass the fuel hose between the hot starter cable and throttle po- sition sensor lead.
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CABLE ROUTING DIAGRAM Hot starter cable 12. Engine stop switch lead Fasten the hot starter cable and Clamp 13. Sub-wire harness throttle cables onto the frame. Throttle position sensor lead 14. Ground lead Locate the clamp ends under Hump (frame) 15.
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CABLE ROUTING DIAGRAM Fasten the throttle position sen- sor lead to the frame behind its hump. Pass the neutral switch lead on the inside of the engine bracket. Pass the neutral switch lead over the lower engine guard stay. Fasten the neutral switch lead and radiator breather hose to the frame.
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CABLE ROUTING DIAGRAM Throttle cable (pull) Fasten the throttle cables with Throttle cable (return) the clamp so that the cables are Radiator hose 2 not bent, and pass them under Ignition coil the rear arm bracket. Rear arm bracket Pass the cylinder head breather Cylinder head breather hose hose so that it does not contact Pass the throttle cables over the...
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CABLE ROUTING DIAGRAM Brake master cylinder If the brake hose contacts the Brake hose holder spring (rear shock absorber), Brake hose correct its twist. Install the brake hose so that its Install the brake hose so that its pipe portion directs as shown pipe portion directs as shown and lightly touches the projec- and lightly touches the projec-...
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CABLE ROUTING DIAGRAM Throttle cable Pass the clutch cable and hot Clamp starter cable through the cable Hot starter cable guide. Clutch cable Pass the brake hose in front of Engine stop switch lead the number plate. Cable guide Pass the throttle cables through Brake hose the cable guide.
The following schedule is intended as a general guide to maintenance and lubrication. Bear in mind that such factors as weather, terrain, geographical location, and individual usage will alter the required maintenance and lubrication intervals. If you are a doubt as to what intervals to follow in maintaining and lubricating your machine, consult your Yamaha dealer. Every...
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MAINTENANCE INTERVALS Every Every After third fifth (or Every As re- Item break- Remarks race (or 500 1,000 quired ● Replace TRANSMISSION ● Inspect ● Replace bearing SHIFT FORK, SHIFT CAM, GUIDE BAR ● Inspect Inspect wear. ROTOR NUT ● ●...
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MAINTENANCE INTERVALS Every Every After third fifth (or Every As re- Item break- Remarks race (or 500 1,000 quired ● ● Lubricate pivot point ● ● Check brake disc surface ● ● Check fluid level and leakage ● ● Retighten brake disc bolts, cali- per bolts, master cylinder bolts and union bolts ●...
Remarks race (or 500 1,000 quired THROTTLE, CONTROL CABLE ● ● Check routing and connection Yamaha cable lube or SAE 10W-30 motor oil ● ● Lubricate HOT STARTER, CLUTCH LEVER ● Inspect free play PRE-OPERATION INSPECTION AND MAINTENANCE Before riding for break-in operation, practice or a race, make sure the machine is in good operating condition.
ENGINE ENGINE gine. 2. Remove: CHECKING THE COOLANT LEVEL • Engine guard "1" • Coolant drain bolt "2" Do not remove the radiator cap "1", drain bolt and hoses when the engine and radiator are hot. Scald- ing hot fluid and steam may be blown out under pressure, which could cause serious injury.
ENGINE place. • Radiator hose Apply water on the radiator cap seal. → Swelling Replace. ADJUSTING THE CLUTCH CABLE FREE PLAY 1. Check: • Clutch lever free play "a" → Out of specification Adjust. ADJUSTING THE THROTTLE Clutch lever free play "a" CABLE FREE PLAY 1.
ENGINE LUBRICATING THE THROTTLE 1. Remove: • Cover (throttle cable cap) "1" • Cover (grip cap) "2" • Throttle grip cap "3" 5. Install: • Air filter guide "1" CLEANING THE AIR FILTER ELEMENT Align the projection "a" on filter guide with the hole "b"...
ENGINE • Do not allow foreign material to CHECKING THE ENGINE OIL enter the crankcase. LEVEL 1. Stand the machine on a level sur- face. • When checking the oil level make sure that the machine is upright. • Place the machine on a suitable (For USA and CDN) stand.
ENGINE 7. Install: • Oil filler cap Replacement steps: 8. Inspect: a. Remove the oil filter element cov- • Engine (for oil leaks) er "1" and oil filter element "2". • Oil level b. Check the O-rings "3", if cracked Refer to "ENGINE OIL LEVEL IN- or damaged, replace them with a SPECTION".
ENGINE ADJUSTING THE VALVE • Identity each valve lifter and pad CLEARANCE position very carefully so that they can be reinstalled in their original place. • The valve clearance should be ad- justed when the engine is cool to the touch. •...
ENGINE BLE". The field where these two coordinates intersect shows the new pad number to use. Use the new pad number only as a guide when verifying the valve clear- ance adjustment. f. Install the new pads "3" and the valve lifters "4".
CHASSIS CHASSIS reached; then release the lever or pedal. BLEEDING THE HYDRAULIC BRAKE SYSTEM Bleed screw: 6 Nm (0.6 m•kg, 4.3 ft•lb) Bleed the brake system if: Repeat steps (e) to (h) until of the • The system has been disassem- air bubbles have been removed bled.
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CHASSIS e. Connect the transparent hose "5" Install the pad pin plug "10". to the bleed screw "6" and place Pad pin plug: the suitable container under its 3 Nm (0.3 m•kg, 2.2 end. ft•lb) CHECKING AND REPLACING THE FRONT BRAKE PADS 1.
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CHASSIS this point. PADS" section. 2. Inspect: • Rear brake pad insulator "1" → Damage Replace. b. Loosen the pad pin "3". c. Remove the rear wheel "4" and Install the brake caliper "12" and brake caliper "5". rear wheel "13". Refer to "FRONT WHEEL AND Refer to "FRONT WHEEL AND REAR WHEEL"...
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CHASSIS hold as illustrated. chain" position. → Stiff Replace the drive chain. CHECKING THE DRIVE CHAIN 1. Measure: 3. Adjust: • Drive chain length (15 links) "a" 5. Install: • Drive chain slack → Out of specification Replace. • Drive chain "1" •...
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CHASSIS CHECKING THE FRONT FORK • Air bleed screw ADJUSTING THE FRONT FORK 1. Inspect: COMPRESSION DAMPING FORCE Air bleed screw: • Front fork smooth action 1. Adjust: 1 Nm (0.1 m•kg, 0.7 Operate the front brake and • Compression damping force ft•lb) stroke the front fork.
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CHASSIS of the adjuster. Extent of adjustment: • The I.D. mark "b" is marked at the end of the spring. Maximum Minimum • The standard length and extent of adjustment vary according to the 20 clicks out Fully turned in quantity of I.D.
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CHASSIS CHECKING AND TIGHTENING THE SPOKES 1. Inspect: • Spokes "1" → Bend/damage Replace. → Loose spoke Retighten. 2. Tighten: • Spokes • STANDARD POSITION: • STANDARD POSITION: Spokes: This is the position which is back This is the position which is back 3 Nm (0.3 m•kg, 2.2 by the specific number of clicks by the specific number of turns...
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Footrest pivot avoid getting grease on the brake Throttle-to-handlebar contact discs. Drive chain Tube guide cable winding por- tion Throttle cable end Clutch cable end 10. Hot starter cable end Use Yamaha cable lube or equivalent on these areas. 3-21...
SEAT, FUEL TANK AND SIDE COVERS ENGINE SEAT, FUEL TANK AND SIDE COVERS REMOVING THE SEAT, FUEL TANK AND SIDE COVERS Order Part name Q'ty Remarks Turn the fuel cock to "OFF". Disconnect the fuel hose. Seat Air scoop (left and right) Bolt (fuel tank) Fuel tank Left side cover...
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SEAT, FUEL TANK AND SIDE COVERS REMOVING THE SIDE COVER 1. Remove: Put the portion "a" of the flap of the air • Bolt (side cover) filter case on the inside of the air • Left side cover "1" scoop. •...
EXHAUST PIPE AND SILENCER EXHAUST PIPE AND SILENCER REMOVING THE EXHAUST PIPE AND SILENCER Order Part name Q'ty Remarks Refer to "SEAT, FUEL TANK AND SIDE Right side cover COVERS" section. Bolt (silencer clamp) Only loosening. Bolt [silencer (front)] Bolt [silencer (rear)] Collar Silencer Silencer clamp...
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EXHAUST PIPE AND SILENCER CHECKING THE SILENCER AND EXHAUST PIPE First, temporarily tighten the nut (ex- 1. Inspect: haust pipe), then tighten the bolt (ex- • Gasket "1" haust pipe) 13 Nm (1.3 m•kg, 9.4 → Damage Replace. ft•lb). After that, retighten the nut (ex- haust pipe) 20 Nm (2.0 m•kg, 14 ft•lb) and then the bolt (exhaust pipe) 20 Nm (2.0 m•kg, 14 ft•lb).
RADIATOR RADIATOR REMOVING THE RADIATOR Order Part name Q'ty Remarks Refer to "CHANGING THE COOLANT" sec- Drain the coolant. tion in the CHAPTER 3. Refer to "SEAT, FUEL TANK AND SIDE Seat and fuel tank COVERS" section. Refer to "EXHAUST PIPE AND SILENCER" Exhaust pipe section.
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RADIATOR HANDLING NOTE Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may be blown out under pressure, which could cause serious injury. When the engine has cooled, open 2. Install: the radiator cap by the following •...
CARBURETOR CARBURETOR REMOVING THE CARBURETOR Order Part name Q'ty Remarks Refer to "SEAT, FUEL TANK AND SIDE Seat and fuel tank COVERS" section. Refer to "REAR SHOCK ABSORBER" sec- Rear shock absorber tion in the CHAPTER 5. Clamp Throttle position sensor lead coupler Throttle cable cover Throttle cable Clamp (air filter joint)
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CARBURETOR DISASSEMBLING THE CARBURETOR Order Part name Q'ty Remarks Carburetor breather hose Valve lever housing cover Screw (throttle shaft) Throttle valve Needle holder Jet needle Accelerator pump cover Spring Diaphragm (accelerator pump) Float chamber Leak jet Pilot screw Refer to removal section. Float pin Float Needle valve...
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CARBURETOR Order Part name Q'ty Remarks Pilot jet Starter jet Push rod Pull the push rod. Throttle shaft assembly Push rod link lever assembly Pilot air jet Cold starter plunger...
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CARBURETOR → HANDLING NOTE Damage Replace. → Contamination Clean. Do not loosen the screw (throttle • Use a petroleum based solvent for position sensor) "1" except when cleaning. Blow out all passages and changing the throttle position sen- jets with compressed air. sor due to failure because it will •...
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CARBURETOR • Spring 2 "6" carburetor. → Dirt Clean. f. Recheck the float height. 6. Install: ASSEMBLING THE CARBURETOR CHECKING THE FLOAT • Washer "1" 1. Install: 1. Inspect: • Circlip "2" • Cold starter plunger "1" • Float "1" →...
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CARBURETOR • Check the float for smooth move- ment. Install the diaphragm (accelerator pump) with its mark "a" facing the spring. 12. Install: • Pilot screw "1" • Spring "2" 15. Install: • Washer "3" • Jet needle "1" • O-ring "4" •...
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CARBURETOR 2. Install: • Carburetor "1" Install the projection "a" between the carburetor joint slots. ADJUSTING THE ACCELERATOR 6. Adjust: PUMP TIMING • Throttle grip free play Refer to "ADJUSTING THE THROTTLE CABLE FREE PLAY" Adjustment steps: section in the CHAPTER 3. 7.
CAMSHAFTS CAMSHAFTS REMOVING THE CYLINDER HEAD COVER Order Part name Q'ty Remarks Refer to "SEAT, FUEL TANK AND SIDE Seat and fuel tank COVERS" section. Hot starter plunger Refer to "CARBURETOR" section. Engine upper bracket (right) Refer to "ENGINE REMOVAL" section. Engine upper bracket (left) Spark plug Cylinder head breather hose...
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CAMSHAFTS REMOVING THE CAMSHAFTS Order Part name Q'ty Remarks Timing mark accessing screw Refer to removal section. Crankshaft end accessing screw Refer to removal section. Timing chain tensioner cap bolt Refer to removal section. Timing chain tensioner Refer to removal section. Gasket Refer to removal section.
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CAMSHAFTS REMOVING THE CAMSHAFT Cam lobes length: 1. Remove: Intake "a": • Timing mark accessing screw "1" 31.200–31.300 mm • Crankshaft end accessing screw (1.2283–1.2323 in) "2" <Limit>: 31.100 mm (1.2244 in) Intake "b": 22.550–22.650 mm 4. Remove: (0.8878–0.8917 in) •...
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CAMSHAFTS Camshaft-to-cap clear- ance: 0.028–0.062 mm (0.0011–0.0024 in) <Limit>:0.08 mm (0.003 CHECKING THE CAMSHAFT Measurement steps: SPROCKET a. Install the camshaft onto the cylin- 1. Inspect: der head. • Camshaft sprocket "1" ® b. Position a strip of Plastigauge → Wear/damage Replace the "1"...
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CAMSHAFTS b. With the rod fully wound and the chain tensioner UP mark "a" fac- Do not turn the crankshaft during ing upward, install the gasket "1", the camshaft installation. Damage the timing chain tensioner "2", and or improper valve timing will re- the gasket "3", and tighten the bolt sult.
CYLINDER HEAD CYLINDER HEAD REMOVING THE CYLINDER HEAD Order Part name Q'ty Remarks Refer to "SEAT, FUEL TANK AND SIDE Seat and fuel tank COVERS" section. Refer to "EXHAUST PIPE AND SILENCER" Exhaust pipe and silencer section. Radiator Refer to "RADIATOR" section Carburetor Refer to "CARBURETOR"...
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CYLINDER HEAD CHECKING THE CYLINDER HEAD • Cylinder head gasket "3" e. Remove the bolts. 1. Eliminate: • Cylinder head "4" f. Again apply the molybdenum dis- • Carbon deposits (from the com- ulfide grease on the threads and bustion chambers) contact surfaces of the bolts and While pulling up the timing chain, in- Use a rounded scraper.
VALVES AND VALVE SPRINGS VALVES AND VALVE SPRINGS REMOVING THE VALVES AND VALVE SPRINGS Order Part name Q'ty Remarks Cylinder head Refer to "CYLINDER HEAD" section. Valve lifter Refer to removal section. Adjusting pad Refer to removal section. Valve cotter Refer to removal section.
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VALVES AND VALVE SPRINGS REMOVING THE VALVE LIFTER AND VALVE COTTER 1. Remove: • Valve lifter "1" • Pad "2" Identify each lifter "1" and pad "2" po- sition very carefully so that they can CHECKING THE VALVE b. Install the new valve guide using a be reinstalled in their original place.
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VALVES AND VALVE SPRINGS gap between the valve stem and 4. Measure: Valve seat width: the guide. • Margin thickness "a" Intake: → Out of specification Replace. 0.9–1.1 mm (0.0354– Margin thickness: 0.0433 in) Intake: <Limit>:1.6 mm 1.0 mm (0.039 in) (0.0630 in) <Limit>:0.85 mm Exhaust:...
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VALVES AND VALVE SPRINGS 3. Install: CHECKING THE VALVE SPRINGS • Valve cotters 1. Measure: • Valve spring free length "a" → Out of specification Replace. While compressing the valve spring with a valve spring compressor "1" in- Free length (valve stall the valve cotters.
CYLINDER AND PISTON CYLINDER AND PISTON REMOVING THE CYLINDER AND PISTON Order Part name Q'ty Remarks Cylinder head Refer to "CYLINDER HEAD" section. Bolt (cylinder) Cylinder Gasket Dowel pin Piston pin clip Refer to removal section. Piston pin Refer to removal section. Piston Refer to removal section.
CYLINDER AND PISTON 3. Measure: c. Calculate the piston pin-to-piston • Ring end gap clearance with the following for- • Apply engine oil onto the piston pin → Out of specification Replace. mula. and piston. • Be sure that the arrow mark "a" on Piston pin-to-piston clearance = You cannot measure the end gap on the piston points to the exhaust side...
CLUTCH CLUTCH REMOVING THE CLUTCH Order Part name Q'ty Remarks Refer to "CHANGING THE ENGINE OIL" Drain the engine oil. section in the CHAPTER 3. Brake pedal Refer to "ENGINE REMOVAL" section. Clutch cable Disconnect at engine side. Clutch cover Gasket Dowel pin Clutch spring...
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CLUTCH Order Part name Q'ty Remarks Nut (clutch boss) Refer to removal section. Lock washer Refer to removal section. Clutch boss Refer to removal section. Thrust washer Primary driven gear Push lever shaft 4-30...
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CLUTCH → REMOVING THE CLUTCH BOSS CHECKING THE CLUTCH Wear/damage Replace. 1. Remove: SPRINGS • Nut "1" 1. Measure: • Lock washer "2" • Clutch spring free length "a" → • Clutch boss "3" Out of specification Replace springs as a set. Straighten the lock washer tab and Clutch spring free use the clutch holding tool "4"...
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CLUTCH • Nut (clutch boss) "2" Nut (clutch boss): 75 Nm (7.5 m•kg, 54 ft•lb) Make sure to tighten to specifica- tion; otherwise, it may damage the 5. Install: 9. Install: other part that is fastened togeth- • Bearing "1" •...
OIL FILTER ELEMENT AND WATER PUMP OIL FILTER ELEMENT AND WATER PUMP REMOVING THE OIL FILTER ELEMENT AND WATER PUMP 10 Nm (1.0 m kg, 7.2 ft lb) 33 Nm (3.3 m kg, 24 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) 12 Nm (1.2 m kg, 8.7 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb)
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OIL FILTER ELEMENT AND WATER PUMP 10 Nm (1.0 m kg, 7.2 ft lb) 33 Nm (3.3 m kg, 24 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) 12 Nm (1.2 m kg, 8.7 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) 14 Nm (1.4 m kg, 10 ft lb)
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OIL FILTER ELEMENT AND WATER PUMP REMOVING THE IMPELLER SHAFT 1. Remove: • Impeller "1" • Washer "2" • Impeller shaft "3" Hold the impeller shaft on its width CHECKING THE BEARING INSTALLING THE IMPELLER across the flats "a" with spanners, 1.
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OIL FILTER ELEMENT AND WATER PUMP 3. Install: • O-ring "3" • Coolant pipe "1" • Bolt (coolant pipe) "2" Bolt (coolant pipe): 10 Nm (1.0 m•kg, 7.2 ft•lb) 2. Install: 2. Install: • Right crankcase cover "1" • Oil tank breather hose "1" Apply the lithium soap base grease •...
BALANCER BALANCER REMOVING THE BALANCER Order Part name Q'ty Remarks Primary driven gear Refer to "CLUTCH" section. Refer to "OIL FILTER ELEMENT AND WA- Right crankcase cover TER PUMP" section. Stator Refer to "CDI MAGNETO" section. Nut (balancer) Refer to removal section. Nut (primary drive gear) Refer to removal section.
OIL PUMP OIL PUMP REMOVING THE OIL PUMP Order Part name Q'ty Remarks Primary driven gear Refer to "CLUTCH" section. Refer to "OIL FILTER ELEMENT AND WA- Right crankcase cover TER PUMP" section. Circlip Washer Oil pump drive gear Oil pump assembly Dowel pin Outer rotor 2 Circlip...
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OIL PUMP Order Part name Q'ty Remarks Oil pump drive shaft Rotor housing 4-40...
KICK SHAFT AND SHIFT SHAFT KICK SHAFT AND SHIFT SHAFT REMOVING THE KICK SHAFT AND SHIFT SHAFT Order Part name Q'ty Remarks Oil pump Refer to "OIL PUMP" section. Kick idle gear Kick shaft assembly Refer to removal section. Spring guide Torsion spring Ratchet wheel Kick gear...
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KICK SHAFT AND SHIFT SHAFT Order Part name Q'ty Remarks Pawl Pawl pin Spring Bolt (stopper lever) Stopper lever Torsion spring Segment Refer to removal section. 4-43...
KICK SHAFT AND SHIFT SHAFT REMOVING THE KICK SHAFT • Kick shaft "2" CHECKING THE STOPPER LEVER → ASSEMBLY Wear/damage Replace. 1. Inspect: 1. Remove: • Spring "3" • Stopper lever "1" → • Kick shaft assembly "1" Broken Replace. →...
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KICK SHAFT AND SHIFT SHAFT INSTALLING THE SHIFT GUIDE INSTALLING THE SHIFT SHAFT AND SHIFT LEVER ASSEMBLY 1. Install: 1. Install: • Roller "1" • Spring "1" • Collar "2" • Pawl pin "2" • Torsion spring "3" • Pawl "3" •...
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KICK SHAFT AND SHIFT SHAFT 5. Hook: • Torsion spring "1" Turn the torsion spring clockwise and hook into the proper hole "a" in the crankcase. INSTALLING THE KICK IDLE GEAR 1. Install: • Kick idle gear "1" • Washer "2" •...
CDI MAGNETO CDI MAGNETO REMOVING THE CDI MAGNETO Order Part name Q'ty Remarks Seat and fuel tank Refer to "SEAT, FUEL TANK AND SIDE COVERS" section. Disconnect the CDI magneto lead. Left crankcase cover Gasket Dowel pin Nut (rotor) Refer to removal section. Rotor Refer to removal section.
• Apply the sealant on the grommet • Nut (rotor) "1" of the CDI magneto lead. • Washer • Tighten the screws using the T30 bit. YAMAHA Bond No. 1215 ® (ThreeBond No. 1215): 5. Install: 90890-85505 • Dowel pin •...
ENGINE REMOVAL ENGINE REMOVAL REMOVING THE ENGINE Order Part name Q'ty Remarks Hold the machine by placing the suitable stand Refer to "HANDLING NOTE". under the frame. Refer to "SEAT, FUEL TANK AND SIDE Seat and fuel tank COVERS" section. Refer to "REAR SHOCK ABSORBER"...
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ENGINE REMOVAL Order Part name Q'ty Remarks Engine guard Neutral switch Drive chain sprocket cover Nut (drive sprocket) Refer to removal section. Lock washer Refer to removal section. Drive sprocket Refer to removal section. Clip Bolt (brake pedal) Brake pedal Upper engine bracket Lower engine bracket Engine mounting bolt...
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ENGINE REMOVAL HANDLING NOTE Support the machine securely so there is no danger of it falling over. REMOVING THE DRIVE SPROCKET 1. Remove: INSTALLING THE ENGINE • Nut (drive sprocket) "1" 1. Install: • Lock washer "2" • Engine "1" Install the engine from right side.
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ENGINE REMOVAL 2. Install: • Lock washer "1" • Nut (drive sprocket) "2" Nut (drive sprocket): 75 Nm (7.5 m•kg, 54 ft•lb) Tighten the nut while applying the rear brake. Make sure to tighten to specifica- tion; otherwise, it may damage the other part that is fastened togeth- 3.
CRANKCASE AND CRANKSHAFT CRANKCASE AND CRANKSHAFT REMOVING THE CRANKSHAFT Order Part name Q'ty Remarks Engine Refer to "ENGINE REMOVAL" section. Piston Refer to "CYLINDER AND PISTON" section. Balancer Refer to "BALANCER" section. Refer to "KICK SHAFT AND SHIFT SHAFT" Kick shaft assembly section.
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CRANKCASE AND CRANKSHAFT Order Part name Q'ty Remarks Balancer shaft Refer to removal section. Crankshaft Refer to removal section. 4-54...
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CRANKCASE AND CRANKSHAFT REMOVING THE CRANKCASE BEARING Order Part name Q'ty Remarks Refer to "TRANSMISSION, SHIFT CAM AND Transmission SHIFT FORK" section. Refer to "TRANSMISSION, SHIFT CAM AND Shift cam and shift fork SHIFT FORK" section. Oil seal Bearing Refer to removal section. 4-55...
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CRANKCASE AND CRANKSHAFT DISASSEMBLING THE c. Remove the dowel pins and O- CRANKCASE ring. 1. Separate: • Right crankcase REMOVING THE BALANCER • Left crankcase SHAFT 1. Remove: Separation steps: • Balancer shaft "1" a. Remove the crankcase bolts, CHECKING THE TIMING CHAIN hose guide and clutch cable hold- Remove the balancer shaft with its AND TIMING CHAIN GUIDE...
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On the right crankcase. INSTALLING THE CRANKCASE the nut of the installing tool with the BEARING other. Operate the installing tool un- YAMAHA Bond No. 1215 1. Install: ® til the crankshaft bottoms against (ThreeBond No.1215): •...
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CRANKCASE AND CRANKSHAFT 9. Apply: • Engine oil To the crank pin, bearing and oil delivery hole. 10. Check: • Crankshaft and transmission op- eration. → Unsmooth operation Repair. 5. Install: • Dowel pin "1" • O-ring "2" • Right crankcase To left crankcase.
TRANSMISSION, SHIFT CAM AND SHIFT FORK TRANSMISSION, SHIFT CAM AND SHIFT FORK REMOVING THE TRANSMISSION, SHIFT CAM AND SHIFT FORK Order Part name Q'ty Remarks Engine Refer to "ENGINE REMOVAL" section. Refer to "CRANKCASE AND CRANK- Separate the crankcase. SHAFT" section. Main axle Refer to removal section.
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TRANSMISSION, SHIFT CAM AND SHIFT FORK REMOVING THE TRANSMISSION idler gear and on the inner surface of 1. Remove: the sliding gear, then install. • Main axle "1" • Drive axle "2" • Shift cam • Shift fork 3 • Shift fork 2 •...
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TRANSMISSION, SHIFT CAM AND SHIFT FORK 3. Install: • Washer "1" • Circlip "2" • Be sure the circlip sharp-edged cor- ner "a" is positioned opposite side to the washer and gear "b". • Install the circlip with its ends "c" settled evenly on the spline crests.
FRONT WHEEL AND REAR WHEEL CHASSIS FRONT WHEEL AND REAR WHEEL REMOVING THE FRONT WHEEL Order Part name Q'ty Remarks Hold the machine by placing the suitable stand Refer to "HANDLING NOTE". under the engine. Bolt (axle holder) Only loosening. Nut (front wheel axle) Front wheel axle Front wheel...
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FRONT WHEEL AND REAR WHEEL REMOVING THE REAR WHEEL Order Part name Q'ty Remarks Hold the machine by placing the suitable stand Refer to "HANDLING NOTE". under the engine. Nut (rear wheel axle) Rear wheel axle Drive chain puller Rear wheel Refer to removal section.
FRONT WHEEL AND REAR WHEEL HANDLING NOTE Support the machine securely so there is no danger of it falling over. REMOVING THE REAR WHEEL 1. Remove: • Wheel "1" CHECKING THE WHEEL AXLE 1. Measure: Push the wheel forward and remove •...
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FRONT WHEEL AND REAR WHEEL 6. Install: 2. Install: • Nut (wheel axle) "1" • Brake disc "1" Do not strike the inner race of the • Bolt (brake disc) "2" Nut (wheel axle): bearing. Contact should be made 105 Nm (10.5 m•kg, 75 Bolt (brake disc): only with the outer race.
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FRONT WHEEL AND REAR WHEEL 4. Install: Temporarily tighten the nut (wheel • Collar "1" axle) at this point. Apply the lithium soap base grease on the oil seal lip. 9. Adjust: • Drive chain slack "a" 5. Install: Drive chain slack: •...
FRONT BRAKE AND REAR BRAKE FRONT BRAKE AND REAR BRAKE REMOVING THE FRONT BRAKE Order Part name Q'ty Remarks Hold the machine by placing the suitable stand Refer to "HANDLING NOTE". under the engine. Drain the brake fluid. Refer to removal section. Brake hose holder (protector) Union bolt Brake hose...
FRONT BRAKE AND REAR BRAKE REMOVING THE REAR BRAKE Order Part name Q'ty Remarks Hold the machine by placing the suitable stand Refer to "HANDLING NOTE". under the engine. Refer to "FRONT WHEEL AND REAR Rear wheel WHEEL" section. Drain the brake fluid. Refer to removal section.
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FRONT BRAKE AND REAR BRAKE DISASSEMBLING THE BRAKE CALIPER Order Part name Q'ty Remarks Front Rear Pad pin Brake pad Pad support Brake caliper piston Refer to removal section. Brake caliper piston dust seal Refer to removal section. Brake caliper piston seal Refer to removal section.
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FRONT BRAKE AND REAR BRAKE DISASSEMBLING THE BRAKE MASTER CYLINDER Order Part name Q'ty Remarks Front Rear Brake master cylinder cap Diaphragm Reservoir float Push rod (Front) Brake master cylinder boot Circlip Use a long nose circlip pliers. Washer Push rod (Rear) Brake master cylinder kit...
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FRONT BRAKE AND REAR BRAKE HANDLING NOTE • Cover piston with rag and use ex- Support the machine securely so treme caution when expelling there is no danger of it falling over. piston from cylinder. • Never attempt to pry out piston. DRAINING THE BRAKE FLUID 1.
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FRONT BRAKE AND REAR BRAKE seals and brake caliper piston dust seals whenever a caliper is disassembled. INSTALLING THE BRAKE CALIPER PISTON 1. Clean: • Brake caliper • Brake caliper piston seal CHECKING THE BRAKE CALIPER • Brake caliper piston dust seal 1.
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FRONT BRAKE AND REAR BRAKE 4. Install: • Brake master cylinder kit "1" • Washer (front brake) "2" • Push rod (rear brake) "2" • Circlip "3" • Brake master cylinder boot "4" • Push rod (front brake) "5" To brake master cylinder. INSTALLING THE REAR BRAKE INSTALLING THE BRAKE CALIPER...
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FRONT BRAKE AND REAR BRAKE 2. Install: 2. Install: • Union bolt "3" • Brake master cylinder "1" • Brake lever "1" Union bolt: • Bolt (brake master cylinder) "2" • Bolt (brake lever) "2" 30 Nm (3.0 m•kg, 22 Bolt (brake master cylin- Bolt (brake lever): ft•lb)
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FRONT BRAKE AND REAR BRAKE lower the boiling point of the flu- 4. Install: id and may result in vapor lock. • Copper washer "1" • Brake hose "2" • Union bolt "3" Brake fluid may erode painted sur- Union bolt: faces or plastic parts.
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FRONT BRAKE AND REAR BRAKE A. Front B. Rear 5. Install: (rear brake only) • Protector "1" • Bolt (protector) "2" Bolt (protector): 7 Nm (0.7 m•kg, 5.1 ft•lb) 5-15...
FRONT FORK FRONT FORK REMOVING THE FRONT FORK 21 Nm (2.1 m kg, 15 ft lb) 21 Nm (2.1 m kg, 15 ft lb) 7 Nm (0.7 m kg, 5.1 ft lb) 5 Nm (0.5 m kg, 3.6 ft lb) 5 Nm (0.5 m kg, 3.6 ft lb) Order Part name...
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FRONT FORK DISASSEMBLING THE FRONT FORK 30 Nm (3.0 m kg, 22 ft lb) 29 Nm (2.9 m kg, 21 ft lb) 1 Nm (0.1 m kg, 0.7 ft lb) 29 Nm (2.9 m kg, 21 ft lb) 55 Nm (5.5 m kg, 40 ft lb) Order Part name Q'ty...
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FRONT FORK HANDLING NOTE Support the machine securely so there is no danger of it falling over. The front fork requires careful atten- tion. So it is recommended that the 3. Remove: front fork be maintained at the deal- • Adjuster "1" ers.
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FRONT FORK → Contamination Clean. half of the dial gauge reading. enter the front fork. • O-ring "2" → Wear/damage Replace. • Piston metal "3" Do not attempt to straighten a bent → Wear/damage Replace. inner tube as this may dangerous- •...
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FRONT FORK 15. Install: • Dust seal "1" • Stopper ring "2" • Oil seal "3" • Oil seal washer "4" • Slide metal "5" To inner tube "6". 7. Loosen: 11. After filling, pump the damper as- • Apply the fork oil on the inner tube. •...
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FRONT FORK tube with fork seal driver "3". vertically, the damper assembly may fall into it, damaging the valve inside. Fork seal driver: YM-A0948/90890-01502 22. Check: • Inner tube smooth movement Tightness/binding/rough spots → Repeat the steps 15 to 21. 26.
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FRONT FORK adjust each front fork to the same setting. Uneven adjustment can If the adjuster is installed out of spec- cause poor handling and loss of ification, proper damping force can- stability. not be obtained. • Be sure to use recommended fork oil.
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FRONT FORK 5. Install: • Protector "1" • Bolt (protector) "2" Bolt (protector): 5 Nm (0.5 m•kg, 3.6 ft•lb) 6. Adjust: • Rebound damping force Turn in the damping adjuster "1" fin- ger-tight and then turn out to the orig- inally set position.
HANDLEBAR HANDLEBAR REMOVING THE HANDLEBAR Order Part name Q'ty Remarks Number plate Remove the band only. Hot starter cable Disconnect at the lever side. Hot starter lever holder Clutch cable Disconnect at the lever side. Clutch lever holder Engine stop switch Brake master cylinder Refer to removal section.
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HANDLEBAR REMOVING THE BRAKE MASTER tance "a" from the mounting bolt CYLINDER center facing forward. 1. Remove: • Apply the lithium soap base grease • Brake master cylinder bracket "1" on the thread of the handlebar low- • Brake master cylinder "2" er holder.
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HANDLEBAR 5. Install: 8. Install: • Right grip "1" • Throttle cable cap "1" • Collar "2" • Screw (throttle cable cap) "2" Apply the adhesive on the tube Screw (throttle cable guide "3". cap): 4 Nm (0.4 m•kg, 2.9 •...
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HANDLEBAR 13. Adjust: • Clutch lever free play Refer to "ADJUSTING THE CLUTCH CABLE FREE PLAY" section in the CHAPTER 3. • Hot starter lever free play Refer to "ADJUSTING THE HOT STARTER LEVER FREE PLAY" section in the CHAPTER 3. 5-27...
STEERING STEERING REMOVING THE STEERING Order Part name Q'ty Remarks TIGHTENING STEPS: • Tighten ring nut. 38 Nm (3.8 m•kg, 27 ft•lb) • Loosen it one turn. • Retighten it. 7 Nm (0.7 m•kg, 5.1 ft•lb) Hold the machine by placing the suitable stand Refer to "HANDLING NOTE".
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STEERING Order Part name Q'ty Remarks Bearing race Refer to removal section. 5-29...
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STEERING HANDLING NOTE Support the machine securely so there is no danger of it falling over. REMOVING THE STEERING RING 1. Remove: CHECKING THE BEARING AND 3. Install: • Steering ring nut "1" BEARING RACE • Lower bracket "1" Use the steering nut wrench "2". 1.
SWINGARM SWINGARM REMOVING THE SWINGARM Order Part name Q'ty Remarks Hold the machine by placing the suitable stand Refer to "HANDLING NOTE". under the engine. Refer to "FRONT BRAKE AND REAR Brake hose holder BRAKE" section. Refer to "FRONT BRAKE AND REAR Rear brake caliper BRAKE"...
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SWINGARM DISASSEMBLING THE SWINGARM Order Part name Q'ty Remarks Refer to removal section. Relay arm Connecting rod Collar Oil seal Thrust bearing Bushing Oil seal Bearing Refer to removal section. 5-33...
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SWINGARM HANDLING NOTE 2. Inspect: • Oil seal "3" → Damage Replace. Support the machine securely so there is no danger of it falling over. REMOVING THE CAP 1. Remove: • Left cap "1" 2. Install: • Bearing "1" Remove with a slotted-head screw- •...
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SWINGARM • Washer "3" • Swingarm up and down move- • Nut (connecting rod) "4" ment "b" Unsmooth movement/binding/ Nut (connecting rod): → rough spots Grease or replace 80 Nm (8.0 m•kg, 58 bearings, bushings and collars. ft•lb) To relay arm "5". INSTALLING THE SWINGARM Apply the molybdenum disulfide 1.
REAR SHOCK ABSORBER REAR SHOCK ABSORBER REMOVING THE REAR SHOCK ABSORBER Order Part name Q'ty Remarks Hold the machine by placing the suitable stand Refer to "HANDLING NOTE". under the engine. Refer to "SEAT, FUEL TANK AND SIDE Seat COVERS" section in the CHAPTER 4. Refer to "EXHAUST PIPE AND SILENCER"...
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REAR SHOCK ABSORBER Order Part name Q'ty Remarks Bearing Refer to removal section. 5-38...
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To dispose of a damaged or worn- • Stopper ring (upper bearing) "1" ABSORBER out rear shock absorber, take the 1. Inspect: unit to your Yamaha dealer for this • Damper rod "1" disposal procedure. After installing the stopper ring, push →...
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REAR SHOCK ABSORBER 3. Tighten: • Adjuster "1" 3. Install: 3. Install: • Lower bearing "1" • Rear shock absorber 4. Install: 4. Adjust: • Bolt (rear shock absorber-frame) Install the bearing by pressing it on • Spring length (installed) "1"...
IGNITION SYSTEM IGNITION SYSTEM INSPECTION STEPS Use the following steps for checking the possibility of the malfunctioning engine being attributable to ignition system failure and for checking the spark plug which will not spark. → Spark gap test Spark *Clean or replace spark plug. ↓...
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IGNITION SYSTEM SPARK GAP TEST Result 1. Disconnect the ignition coil from Conductive (while the spark plug. engine stop switch is 2. Remove the ignition coil cap. pushed) 3. Connect the dynamic spark tester → Not conductive while it is pushed "1"...
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IGNITION SYSTEM 3. Inspect: • Charging coil 2 resistance → Out of specification Replace. → Tester (+) lead Pink lead "1" → Tester (-) lead Black lead "2" Charging Tester se- coil 2 resis- lector posi- tance tion Ω 44-66 Ω...
THROTTLE POSITION SENSOR SYSTEM THROTTLE POSITION SENSOR SYSTEM INSPECTION STEPS If the throttle position sensor will not operate, use the following inspection steps. → Check entire ignition system for connection. No good Repair or replace. ↓ → Check throttle position sensor. (Throttle position No good Replace.
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THROTTLE POSITION SENSOR SYSTEM HANDLING NOTE 3. Inspect: • Temporarily tighten the screw • Throttle position sensor coil vari- (throttle position sensor). able resistance Do not loosen the screw (throttle Check that the resistance in in- position sensor) "1" except when creased as the throttle grip is changing the throttle position sen- moved from the full close position...
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THROTTLE POSITION SENSOR SYSTEM Throttle po- Throttle po- Tester se- Tester se- sition sen- sition sen- lector posi- lector posi- sor input sor output tion tion voltage voltage 4–6 V DCV-20 0.58–0.78 V 10. Put the aligning marks "a" on the throttle position sensor and car- buretor.
ENGINE TUNING correctly and opens and closes CONSTRUCTION OF smoothly. CARBURETOR AND SETTING ENGINE PARTS ATMOSPHERIC CONDITIONS AND CARBURETOR SETTING The FLATCR carburetor has a prima- CARBURETOR SETTINGS • The air/fuel mixture will vary de- ry main jet. This type of main jet is pending on atmospheric conditions.
ENGINE #160 Effects of adjusting the pilot jet Diameter of the straight por- (reference) tion ADJUSTING THE PILOT SCREW Reference needle The richness of the air-fuel mixture 0.5 richer with the throttle fully closed to 1/4 open can be set by turning the pilot screw "1".
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ENGINE ADJUSTING THE LEAK JET CARBURETOR SETTING PARTS (ADJUSTING THE ACCELERATOR PUMP) Main jet Size Part number The leak jet "1" is a setting part that Rich #172 4MX-14943-92 adjusts the flow of fuel discharged by #170 4MX-14943-41 the accelerator pump. Since the ac- celerator pump operates only when #168 4MX-14943-91...
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ENGINE * This should be taken simply for an example. It is necessary to set the carburetor while checking the operating conditions of the engine.
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CHASSIS CHASSIS DRIVE AND REAR WHEEL The front fork setting includes the fol- SPROCKETS SETTING PARTS lowing three factors: SELECTION OF THE SECONDARY 1. Setting of air spring characteris- REDUCTION RATIO (SPROCKET) Part name Size Part number tics • Change the fork oil amount. Secondary reduction ratio = Drive 2.
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CHASSIS C. Stroke the end of the spring. adjustment by turning the spring Max. oil amount adjuster "2" to achieve the stan- Standard oil amount dard figure from the subtraction of Min. oil amount the length "b" from the length "a". SETTING OF SPRING AFTER Standard figure: REPLACEMENT...
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CHASSIS does not exceed the standard as it [Unequal-pitch steel spring] [Titanium spring] may result in faulty performance. SPRING SPRI EXTENT OF AD- Never use one whose overall SPRING FREE JUSTMENT "b" length is greater than standard. PART I.D. LENGTH NUM- MARK/ One I.D.
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CHASSIS SUSPENSION SETTING (FRONT FORK) • If any of the following symptoms is experienced with the standard position as the base, make resetting by reference to the adjustment procedure given in the same chart. • Before any change, set the rear shock absorber sunken length to the standard figure 90–100 mm (3.5–3.9 in). Section Medi- Symptom...
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CHASSIS SUSPENSION SETTING (REAR SHOCK ABSORBER) • If any of the following symptoms is experienced with the standard position as the base, make resetting by reference to the adjustment procedure given in the same chart. • Adjust the rebound damping in 2-click increments or decrements. •...
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YAMAHA MOTOR CO., LTD. PRINTED ON RECYCLED PAPER PRINTED IN JAPAN 2500 SHINGAI IWATA SHIZUOKA JAPAN...