Yamaha WR250F Owner's Service Manual
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Yamaha WR250F Owner's Service Manual

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2008
OWNER'S SERVICE MANUAL
WR250F(X)
5UM-28199-71

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Summary of Contents for Yamaha WR250F

  • Page 1 2008 OWNER’S SERVICE MANUAL WR250F(X) 5UM-28199-71...
  • Page 3 WR250F (X) OWNER'S SERVICE MANUAL ©2007 by Yamaha Motor Co., Ltd. 1st Edition, July 2007 All rights reserved. Any reprinting or unauthorized use without the written permission of Yamaha Motor Co., Ltd. is expressly prohibited. Printed in Japan...

  • Page 4: Important Notice

    Always turn off the engine Congratulations on your purchase of damage to the machine. while refueling. Take care to a Yamaha WR series. This model is not spill any gasoline on the the culmination of Yamaha's vast ex- engine or exhaust system.
  • Page 5 The information has tion or maintenance of your machine, been complied to provide the me- please consult your Yamaha dealer. chanic with an easy to read, handy reference that contains comprehen- This manual should be considered a...
  • Page 6 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.

  • Page 7: Table Of Contents

    TABLE OF CONTENTS GENERAL INFORMATION SPECIFICATIONS REGULAR INSPECTION AND ADJUSTMENTS TUNING ENGINE CHASSIS ELECTRICAL...

  • Page 8: General Information

    CONTENTS CHAPTER 1 CHAPTER 3 CRANKCASE AND CRANKSHAFT ....5-56 GENERAL INFOR- REGULAR INSPEC- TRANSMISSION, SHIFT MATION TION AND AD- CAM AND SHIFT FORK.5-62 JUSTMENTS CHAPTER 6 DESCRIPTION ....1-1 CHASSIS MACHINE MAINTENANCE IDENTIFICATION ..... 1-2 INTERVALS...... 3-1 INCLUDED PARTS ..1-2 PRE-OPERATION IMPORTANT FRONT WHEEL AND...

  • Page 9: Description

    DESCRIPTION GENERAL INFORMATION DESCRIPTION Clutch lever 14. Headlight Hot starter lever 15. Radiator Engine stop switch 16. Coolant drain bolt Multi-function display 17. Rear brake pedal Main switch 18. Valve joint Start switch 19. Fuel cock Front brake lever 20. Cold starter knob Throttle grip 21.

  • Page 10: Identification

    There are two significant reasons for knowing the serial number of your machine: 1. When ordering parts, you can give the number to your Yamaha dealer for positive identification of the model you own. SPARK PLUG WRENCH 2. If your machine is stolen, the au- This spark plug wrench "1"...

  • Page 11: Checking Of Connection

    CHECKING OF CONNECTION 7. Check for continuity with a tester. ALL REPLACEMENT PARTS 1. We recommend to use Yamaha genuine parts for all replace- • If there in no continuity, clean the ments. Use oil and/or grease rec- terminals. ommended by Yamaha for •...

  • Page 12: Special Tools

    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.
  • Page 13 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. Damper rod holder Use this tool to remove and install YM-01494, 90890-01494 the damper rod. Fork seal driver This tool is used when install the fork YM-A0948, 90890-01502...
  • Page 14 SPECIAL TOOLS Tool name/Part number How to use Illustration Valve spring compressor This tool is needed to remove and YM-4019, 90890-04019 install the valve assemblies. Clutch holding tool This tool is used to hold the clutch YM-91042, 90890-04086 when removing or installing the clutch boss securing nut.
  • Page 15 How to use Illustration Vacuum/pressure pump gauge set This tool is used to check the air in- YB-35956-A, 90890-06756 duction system. YAMAHA Bond No. 1215 (ThreeB- This sealant (Bond) is used for ® No. 1215) crankcase mating surface, etc. 90890-85505...

  • Page 16: Control Functions

    CONTROL FUNCTIONS CONTROL FUNCTIONS CLUTCH LEVER The clutch lever "1" is located on the MAIN SWITCH left handlebar; it disengages or en- Functions of the respective switch po- gages the clutch. Pull the clutch lever sitions are as follows: to the handlebar to disengage the clutch, and release the lever to en- The engine can be started only at this gage the clutch.

  • Page 17: Multi-Function Display

    MULTI-FUNCTION DISPLAY MULTI-FUNCTION DISPLAY Be sure to stop the machine before making any setting changes to the multi-function display. The multi-function display is equipped with the following: COLD STARTER KNOB BASIC MODE: Setting the time When cold, the engine requires a •...
  • Page 18 MULTI-FUNCTION DISPLAY Returning to BASIC MODE from RACE MODE When the machine is made ready for a run by manual start, will It is possible to return to BASIC start flashing. MODE with timer measurement at a 2. Start timer measurement by stop.
  • Page 19 MULTI-FUNCTION DISPLAY 2. Reset all measured data by push- 3. Run the machine and start timer ing the "RST" button for 2 sec- measurement. onds or more. 4. To stop timer measurement, pushing the "SLCT1" button and • Resetting will reset the timer display "SLCT2"...
  • Page 20 MULTI-FUNCTION DISPLAY FUNCTION DIAGRAM A short push on the button changes the operation in the arrowed direction. Meter function A short push on the button changes the operation in both arrowed directions. Function that can be performed whether the time is or is not in operation. A long push on the button changes the operation in the arrowed direction.
  • Page 21 MULTI-FUNCTION DISPLAY The following diagram illustrates the multi-function display regarding the direction and operation condition in- volved in each of its functions. A short push on the button changes the operation in the ar- rowed direction. A short push on the button changes the operation in both arrowed directions.

  • Page 22: Starting And Break-In

    STARTING AND BREAK-IN AIR FILTER MAINTENANCE STARTING AND BREAK-IN 7. Return the cold starter knob to its According to "CLEANING THE AIR original position and run the en- FUEL FILTER ELEMENT" section in the gine at 3,000–5,000 r/min for 1 or Always use the recommended fuel as CHAPTER 3, apply the foam-air-filter 2 minutes.
  • Page 23 STARTING AND BREAK-IN The engine fails to start 4. Operate the machine in the lower Pull the hot starter lever all the way gears at moderate throttle open- out and while holding the lever, kick ings for five to eight minutes. the kickstarter crank 10 to 20 times to 5.

  • Page 24: Torque-Check Points

    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...

  • Page 25: Cleaning And Storage

    CLEANING AND STORAGE CLEANING AND STORAGE STORAGE CLEANING If your machine is to be stored for 60 Frequent cleaning of your machine days or more, some preventive mea- will enhance its appearance, maintain sures must be taken to avoid deterio- good overall performance, and ex- ration.

  • Page 26: Specifications

    GENERAL SPECIFICATIONS SPECIFICATIONS GENERAL SPECIFICATIONS Model name: WR250FX (USA, CDN, AUS, NZ) WR250F (ZA) Model code number: 5UMH (USA) 5UMK (CDN) 5UMM (AUS, NZ, ZA) Dimensions: USA, CDN, ZA AUS, NZ Overall length 2,165 mm (85.24 in) 2,180 mm (85.83 in) ←...

  • Page 27: Chassis

    GENERAL SPECIFICATIONS Air filter: Wet type element Fuel: Type Premium unleaded gasoline only with a research octane number of 95 or higher. Tank capacity 8.0 L (1.76 Imp gal, 2.11 US gal) Reserve 1.1 L (0.24 Imp gal, 0.29 US gal) Carburetor: Type FCR-MX37...

  • Page 28: Maintenance Specifications

    MAINTENANCE SPECIFICATIONS Shock absorber: Front shock absorber Coil spring/oil damper Rear shock absorber Coil spring/gas, oil damper Wheel travel: Front wheel travel 300 mm (11.8 in) Rear wheel travel 310 mm (12.2 in) Electrical: Ignition system Generator system AC magneto Battery type YTZ7S (F) Battery voltage/capacity...
  • Page 29 MAINTENANCE SPECIFICATIONS Item Standard Limit Intake "A" 29.65–29.75 mm (1.1673–1.1713 in) 29.55 mm (1.1634 in) Intake "B" 22.45–22.55 mm (0.8839–0.8878 in) 22.35 mm (0.8799 in) Exhaust "A" 30.399–30.499 mm (1.1968–1.2007 in) 30.299 mm (1.1929 in) Exhaust "B" 22.45–22.55 mm (0.8839–0.8878 in) 22.35 mm (0.8799 in) Camshaft runout limit...

  • Page 30: Specifications

    MAINTENANCE SPECIFICATIONS Item Standard Limit "D" margin thickness (IN) 0.8 mm (0.0315 in) ---- "D" margin thickness (EX) 0.7 mm (0.0276 in) ---- Stem outside diameter (IN) 3.975–3.990 mm (0.1565–0.1571 in) 3.945 mm (0.1553 in) Stem outside diameter (EX) 4.460–4.475 mm (0.1756–0.1762 in) 4.430 mm (0.1744 in) Guide inside diameter (IN)
  • Page 31 MAINTENANCE SPECIFICATIONS Item Standard Limit Tilt limit* (IN) ---- 2.5°/1.6 mm (2.5°/0.063 in) Tilt limit* (EX) ---- 2.5°/1.6 mm (2.5°/0.063 in) Direction of winding (top view) (IN) Clockwise ---- Direction of winding (top view) (EX) Clockwise ---- Piston: Piston to cylinder clearance 0.030–0.055 mm (0.0012–0.0022 in) 0.1 mm (0.004 Piston size "D"...
  • Page 32 MAINTENANCE SPECIFICATIONS Item Standard Limit Oil ring: Dimensions (B × T) 1.50 × 2.25 mm (0.06 × 0.09 in) ---- End gap (installed) 0.10–0.40 mm (0.004–0.016 in) ---- Crankshaft: Crank width "A" 55.95–56.00 mm (2.203–2.205 in) ---- Runout limit "C" 0.03 mm (0.0012 in) 0.05 mm (0.002 Big end side clearance "D"...

  • Page 33: Engine

    MAINTENANCE SPECIFICATIONS Item Standard Limit Carburetor: Type/manufacturer FCR-MX37/KEIHIN ---- I. D. mark 5UME E0 ---- Main jet (M.J) #170 ---- Main air jet (M.A.J) #115 ---- Jet needle (J.N) NJRU ---- Cutaway (C.A) ---- Pilot jet (P.J) ---- Pilot air jet (P.A.J) ---- Pilot outlet (P.O) ø0.9...

  • Page 34: Chassis

    MAINTENANCE SPECIFICATIONS CHASSIS Item Standard Limit Steering system: Steering bearing type Taper roller bearing ---- Front suspension: Front fork travel 300 mm (11.8 in) ---- Fork spring free length 460 mm (18.1 in) 455 mm (17.9 Spring rate, STD K = 4.4 N/mm (0.449 kg/mm, 25.1 lb/in) ---- Optional spring/spacer ----...

  • Page 35: Electrical

    4.6–6.8 k at 20 °C (68 °F) ---- Charging system: System type AC magneto ---- Model (stator)/manufacturer 5UM 30/YAMAHA ---- Normal output 14 V/120 W at 5,000 r/min ---- Ω Charging coil resistance (color) 0.288–0.432 at 20 °C (68 °F) (White–...

  • Page 36: Tightening Torques

    Rectifier capacity (AC) 12 A ---- Rectifier capacity (DC) ---- Electric starting system: Type Constant mesh ---- Starter motor: Model/manufacturer 5UM01/YAMAHA ---- Operation voltage 12 V ---- Output 0.35 kW ---- Ω Armature coil resistance 0.0189–0.0231 at 20 °C (68 °F)
  • Page 37 TIGHTENING TORQUES Tightening torque Part to be tightened Thread size Q'ty m•kg ft•lb Cylinder M6 × 1.0 Balancer weight M6 × 1.0 Balancer shaft driven gear M14 × 1.0 Timing chain guide (intake side) M6 × 1.0 Timing chain tensioner M6 ×...
  • Page 38 TIGHTENING TORQUES Tightening torque Part to be tightened Thread size Q'ty m•kg ft•lb Air induction pipe M6 × 1.0 Air induction pipe clamp M6 × 1.0 Air cut-off valve assembly and bracket M6 × 1.0 Bracket (air cut-off valve) and frame M6 ×...
  • Page 39 TIGHTENING TORQUES Tightening torque Part to be tightened Thread size Q'ty m•kg ft•lb △ Front fork and front fork protector M6 × 1.0 △ Front fork protector and brake hose holder M6 × 1.0 Throttle grip cap M5 × 0.8 △...
  • Page 40 TIGHTENING TORQUES Tightening torque Part to be tightened Thread size Q'ty m•kg ft•lb △ Relay arm and swingarm M14 × 1.5 △ Relay arm and connecting rod M14 × 1.5 △ Connecting rod and frame M14 × 1.5 △ Rear shock absorber and frame M10 ×...
  • Page 41 TIGHTENING TORQUES ELECTRICAL Tightening torque Part to be tightened Thread size Q'ty m•kg ft•lb Stator M5 × 0.8 Holder (AC magneto lead) M5× 0.8 Rotor M12 × 1.25 Refer to NOTE. Neutral switch M5 × 0.8 Starter motor M6 × 1.0 Starter relay terminal M6 ×...
  • Page 42 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.
  • Page 43 TIGHTENING TORQUES 2-18...

  • Page 44: Lubrication Diagrams

    LUBRICATION DIAGRAMS LUBRICATION DIAGRAMS Oil filter element Oil pump Drive axle Main axle Intake camshaft Exhaust camshaft Oil tank Oil delivery pipe To oil tank 2-19...
  • Page 45 LUBRICATION DIAGRAMS Crankshaft Oil filter element Oil tank Oil hose From oil pump 2-20...

  • Page 46: Cable Routing Diagram

    CABLE ROUTING DIAGRAM CABLE ROUTING DIAGRAM Fuel tank breather hose 10. Oil hose 19. Carburetor overflow hose Clamp 11. Clutch cable 20. Catch tank breather hose Diode 12. Starter motor lead Insert the end of the fuel tank Hot starter cable 13.

  • Page 47: Cable Routing Diagram

    CABLE ROUTING DIAGRAM Fasten the throttle cable, hot Fasten the clutch cable, AC starter cable and rectifier/regula- magneto lead and neutral switch tor lead onto the frame. Locate lead onto the frame. Locate the the clamp end facing the lower clamp end near the clutch cable side of the hot starter cable and and cut off the tie end.
  • Page 48 CABLE ROUTING DIAGRAM Throttle cable (pull) Fasten the catch tank hose and Pass the carburetor breather Throttle cable (return) air induction hose (air cut-off hose (of the throttle cable cover) Catch tank hose valve-rear of cylinder head) onto through the hose holder. Ignition coil the frame.
  • Page 49 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-...
  • Page 50 CABLE ROUTING DIAGRAM Clamp Fasten the wire harness, nega- Fasten the wire harness, nega- Positive battery lead tive battery lead and starter mo- tive battery lead and starter mo- Battery tor lead to the upper engine tor lead to the upper engine Negative battery lead bracket (left side).
  • Page 51 CABLE ROUTING DIAGRAM Pass the starter motor lead through the hole in the relay holder. Fit the cover securely. Connect the wire harness to the starter relay. Fasten the catch tank breather hose and catch tank hose to the rear frame. Clamp them close to where they are joined to the frame.
  • Page 52 CABLE ROUTING DIAGRAM Throttle cable 12. Upper bracket Fasten the engine stop switch Clamp 13. Clutch switch coupler lead and clutch switch lead to Brake hose 14. Engine stop switch coupler the handlebar with the plastic Clutch cable 15. Multi-function display coupler bands.
  • Page 53 CABLE ROUTING DIAGRAM Pass the throttle cables, clutch cable and hot starter cable be- tween the upper bracket and multi-function display bracket. Fasten the multi-function display leads to the bracket. Cut off the tie end. Secure the coupler by pushing it into the hole in the multi-function display bracket.

  • Page 54: Regular Inspection And Adjustments

    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...
  • Page 55 MAINTENANCE INTERVALS Every Every After third fifth (or Every As re- Item break- Remarks race (or 500 1,000 quired CLUTCH ● ● Inspect and adjust Inspect housing, friction plate, clutch plate and spring. ● Replace TRANSMISSION ● Inspect ● Replace bearing SHIFT FORK, SHIFT CAM, GUIDE BAR ●...
  • Page 56 MAINTENANCE INTERVALS Every Every After third fifth (or Every As re- Item break- Remarks race (or 500 1,000 quired FUEL TANK, COCK ● ● Clean and inspect BRAKES ● ● Adjust lever position and pedal height ● ● Lubricate pivot point ●...
  • Page 57 Lubricate Lithium base grease THROTTLE, CONTROL CABLE ● ● Check routing and connection ● ● Lubricate Yamaha cable lube or SAE 10W-30 motor oil HOT STARTER, CLUTCH LEVER ● Inspect free play BATTERY ● Check terminal for looseness and corrosion...

  • Page 58: Inspection And Maintenance

    PRE-OPERATION INSPECTION AND MAINTENANCE PRE-OPERATION INSPECTION AND MAINTENANCE Before riding for break-in operation or practice, make sure the machine is in good operating condition. Before using this machine, check the following points. GENERAL INSPECTION AND MAINTENANCE Item Routine Page Check that coolant is filled up to the radiator cap. Check the cool- Coolant P.3-9 –...

  • Page 59: Engine

    ENGINE ENGINE 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 Open the air filter case cover. Right side cover Refer to removal section.
  • Page 60 ENGINE REMOVING THE SIDE COVER 1. Remove: • Bolt (side cover) • Right side cover "1" Draw the side cover backward to re- move it because its claw "a" is insert- ed in the air filter case.
  • Page 61 ENGINE 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 Nut (exhaust pipe) Exhaust pipe Gasket...
  • Page 62 ENGINE CHECKING THE SILENCER AND CHECKING THE COOLANT LEVEL 2. Remove: EXHAUST PIPE • Seat 1. Inspect: • Left side cover Do not remove the radiator cap • Gasket "1" 3. Remove the catch tank hose from "1", drain bolt and hoses when the →...
  • Page 63 ENGINE Handling notes of coolant: The coolant is harmful so it should be handled with special care. • When coolant splashes to your eye. Thoroughly wash your eye with Radiator cap ADJUSTING THE CLUTCH CABLE water and see your doctor. 2.
  • Page 64 ENGINE Never run the engine without the air filter element in place; this would allow dirt and dust to enter the engine and cause rapid wear and possible engine damage. 1. Open the air filter case cover "1" 2. Adjust: 3.
  • Page 65 ENGINE (Except for USA and CDN) Recommended oil: SAE10W30, SAE10W40, SAE15W40, SAE20W40 or SAE20W50 API service SG type or higher, JASO standard 5. Inspect: CHECKING THE ENGINE OIL • Air filter element LEVEL → Damage Replace. 1. Start the engine, warm it up for 6.
  • Page 66 ENGINE • Oil filler cap "4" • Engine oil • Oil tank drain bolt "5" Oil quantity: • Crankcase oil drain bolt "6" Periodic oil change: • Oil filter element drain bolt "7" 1.1 L (0.97 Imp qt, 1.16 Drain the crankcase and oil tank US qt) of its oil.
  • Page 67 ENGINE • The piston must be at Top Dead Center (T.D.C.) on compression stroke to check or adjust the valve clearance. 1. Remove: • Seat • Fuel tank Refer to "SEAT, FUEL TANK AND SIDE COVERS" section. In order to be sure that the piston is at ADJUSTING THE ENGINE IDLING 2.
  • Page 68 ENGINE Pads can only be selected in 0.05 • Place a rag in the timing chain mm increments. space to prevent pads from falling into the crankcase. e. Locate the rounded-off value and • Identity each valve lifter and pad the measured valve clearance in position very carefully so that they the chart "PAD SELECTION TA-...
  • Page 69 ENGINE INTAKE EXHAUST 3-16...

  • Page 70: Chassis

    CHASSIS CLEANING THE SPARK • Silencer cap ARRESTER (For USA) Silencer cap: 5 Nm (0.5 m•kg, 3.6 ft•lb) • Be sure the exhaust pipe and si- lencer are cool before cleaning the spark arrester. First tighten the two screws "a" locat- •...
  • Page 71 CHASSIS Pedal height adjustment steps: a. Loosen the locknut "1". b. Turn the adjusting nut "2" until the pedal height "a" is within specified height. c. Tighten the locknut. 2. Remove: b. Loosen the pad pin "2". • Brake lever cover c.
  • Page 72 CHASSIS Do not reuse the drained brake flu- g. Tighten the bleed screw. Bleed screw: 6 Nm (0.6 m•kg, 4.3 ft•lb) Install the brake caliper "8" and 2. Replace: tighten the pad pin "9". • Brake pad h. Install the brake pad "10" and pad Bolt (brake caliper): pin "11".
  • Page 73 CHASSIS 3. Inspect: • Brake fluid level Refer to "CHECKING THE BRAKE FLUID LEVEL" section. 4. Check: • Brake pedal operation → A softy or spongy feeling Bleed brake system. Refer to "BLEEDING THE HY- Lower level 3. Clean: DRAULIC BRAKE SYSTEM" sec- A.
  • Page 74 CHASSIS e. Tighten the locknuts. When installing the drive chain, apply Locknut: Before checking and/or adjusting, ro- the lithium soap base grease on the 19 Nm (1.9 m•kg, 13 tate the rear wheel through several chain joint and O-rings. ft•lb) revolutions and check the slack sev- eral times to find the tightest point.
  • Page 75 CHASSIS 1. Elevate the front wheel by placing CHECKING THE REAR SHOCK a suitable stand under the engine. ABSORBER Always adjust each front fork to 2. Remove the air bleed screw "1" 1. Inspect: the same setting. Uneven adjust- and release the internal pressure •...
  • Page 76 CHASSIS Standard position: Never attempt to turn the adjuster About 11 clicks out Do not force the adjuster past the beyond the maximum or minimum minimum or maximum extent of setting. adjustment. The adjuster may be damaged. Do not force the adjuster past the minimum or maximum extent of adjustment.
  • Page 77 CHASSIS CHECKING THE WHEELS c. Loosen the steering ring nut "1" 1. Inspect: using the steering nut wrench "2". • Wheel runout Steering nut wrench: Elevate the wheel and turn it. YU-33975/90890-01403 → Abnormal runout Replace. CHECKING THE TIRE PRESSURE 1.
  • Page 78 CHASSIS • Install the collar "6" with the larger inside diameter facing downward. • The handlebar upper holder should be installed with the punched mark "a" forward. • Install the handlebar so that the marks "b" are in place on both sides.
  • Page 79 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. 3-26...

  • Page 80: Electrical

    ELECTRICAL • Charge batteries in a well-venti- ELECTRICAL CHECKING THE IGNITION TIMING lated area. 1. Remove: CHECKING THE SPARK PLUG • Keep batteries away from fire, • Timing mark accessing screw "1" 1. Remove: sparks or open flames (e.g., • Spark plug welding equipment, lighted ciga- 2.
  • Page 81 ELECTRICAL • To reduce the chance of sparks, do not plug in the battery charger until the battery charger leads are connected to the battery. • Before removing the battery charger lead clips from the bat- tery terminals, be sure to turn off the battery charger.
  • Page 82 ELECTRICAL Charging method using a variable voltage charger 3-29...
  • Page 83 ELECTRICAL Charging method using a constant voltage charger 3-30...
  • Page 84 ELECTRICAL 6. Install: • Battery • Battery band 7. Connect: • Battery leads (to the battery terminals) First, connect the positive lead "1", Reserve fuse 3. Remove: then the negative lead "2". ∞ c. If the pocket tester indicates " ", •...
  • Page 85 ELECTRICAL ADJUSTING THE HEADLIGHT BEAMS 1. Adjust: • Headlight beam (vertically) Adjusting steps: a. Turn the adjusting screw "1" in di- rection "a" or "b". Direction "a" Headlight beam is raised. Direction "b" Headlight beam is lowered. 3-32...

  • Page 86: Tuning

    ENGINE TUNING • After installing the carburetor, CONSTRUCTION OF check that the throttle operates CARBURETOR AND SETTING ENGINE correctly and opens and closes PARTS CARBURETOR SETTING smoothly. The FLATCR carburetor has a prima- • The air/fuel mixture will vary de- ry main jet.
  • Page 87 ENGINE ADJUSTING THE PILOT JET ADJUSTING THE LEAK JET Effects of changing the jet needle The richness of the air-fuel mixture (ADJUSTING THE ACCELERATOR groove position (reference) with the throttle open 1/4 or less can PUMP) be set by adjusting the pilot jet "1". The leak jet "1"...
  • Page 88 ENGINE CARBURETOR SETTING PARTS Part Main jet Size number (-14943-) Rich #182 4MX-94 #180 4MX-43 #178 4MX-93 #175 4MX-42 #172 4MX-92 (STD) #170 4MX-41 #168 4MX-91 #165 4MX-40 #162 4MX-90 #160 4MX-39 Lean #158 4MX-89 Part Pilot jet Size number (-14948-) Rich 4MX-07...
  • Page 89 ENGINE EXAMPLES OF CARBURETOR SETTING DEPENDING ON SYMPTOM Symptom Setting Checking → At full throttle Increase main jet calibration no. (Gradual- Discoloration of spark plug If tan color, it Hard breathing is in good condition. Shearing noise If cannot be corrected: Whitish spark plug Clogged float valve seat ↓...
  • Page 90 CHASSIS CHASSIS DRIVE AND REAR WHEEL Extent of adjustment: SPROCKETS SETTING PARTS SELECTION OF THE SECONDARY 100–120 kPa (1.0–1.2 REDUCTION RATIO (SPROCKET) Part name Size Part number kgf/cm , 15–18 psi) Secondary reduction ratio = Drive FRONT FORK SETTING Number of rear wheel sprocket sprocket The front fork setting should be made teeth/Number of drive sprocket...
  • Page 91 CHASSIS • Front fork spring "2" SPRING SPRI I.D. PART TYPE MARK NUMBER RATE (slits) (-23141-) 0.408 5TJ-00 0.418 5TJ-10 SOFT A. Load 0.428 5TJ-20 B. Fork stroke 0.438 5TJ-30 |||| Without adjustment washer 0.449 5TJ-A0 — (standard) 1 adjustment washer 0.459 5TJ-50 STIFF...
  • Page 92 CHASSIS SETTING OF SPRING AFTER REAR SHOCK ABSORBER CHOOSING SET LENGTH REPLACEMENT SETTING PARTS 1. Place a stand or block under the After replacement, be sure to adjust • Rear shock spring "1" engine to put the rear wheel the spring to the set length [sunken SPRIN SPRI above the floor, and measure the...
  • Page 93 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...
  • Page 94 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. •...

  • Page 95: Radiator

    RADIATOR ENGINE RADIATOR REMOVING THE RADIATOR Order Part name Q'ty Remarks Refer to "CHECKING THE COOLANT" sec- Drain the coolant. tion in the CHAPTER 3. Refer to "SEAT, FUEL TANK AND SIDE Seat, fuel tank and left side cover COVERS" section in the CHAPTER 3. Radiator guard Radiator hose clamp Only loosening.
  • Page 96 RADIATOR Order Part name Q'ty Remarks Catch tank breather hose Catch tank...
  • Page 97 RADIATOR HANDLING NOTE To right radiator "7". First fit the inner hook portion "a" and then the outer one "b" onto the radia- Do not remove the radiator cap tor. when the engine and radiator are hot. Scalding hot fluid and steam may be blown out under pressure, which could cause serious injury.

  • Page 98: Carburetor

    CARBURETOR CARBURETOR REMOVING THE CARBURETOR 4 Nm (0.4 m kg, 2.9 ft lb) 2 Nm (0.2 m kg, 1.4 ft lb) 11 Nm (1.1 m kg, 8.0 ft lb) 4 Nm (0.4 m kg, 2.9 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) 3 Nm (0.3 m kg, 2.2 ft lb) 3 Nm (0.3 m kg, 2.2 ft lb) Order...
  • Page 99 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) Air cut valve cover Spring (air cut valve) Diaphragm (air cut valve) Float chamber Leak jet...
  • Page 100 CARBURETOR Order Part name Q'ty Remarks Needle jet Spacer Pilot jet Starter jet Push rod Pull the push rod. Throttle shaft assembly Push rod link lever assembly Main air jet Pilot air jet Cold starter plunger...
  • Page 101 CARBURETOR → HANDLING NOTE Grooved wear "a" Replace. → Dust "b" Clean. Measurement and adjustment • Filter "c" steps: Do not loosen the screw (throttle → Clogged Clean. a. Hold the carburetor in an upside position sensor) "1" except when down position.
  • Page 102 CARBURETOR • Circlip "2" CHECKING THE ACCELERATOR 2. Install: PUMP • Pilot air jet "1" 7. Install: 1. Inspect: • Main air jet "2" • Spring "1" • Diaphragm (accelerator pump) To throttle shaft "2". "1" • Spring (accelerator pump) "2" Install the bigger hook "a"...
  • Page 103 CARBURETOR • Hose holder (carburetor breather 16. Install: hose) "5" • Throttle valve assembly "1" • Screw (throttle shaft) "2" Install the valve lever rollers "3" into the slits "a" of the throttle valve. 9. Install: • Push rod "1" 13.
  • Page 104 CARBURETOR a. Fully turn in the accelerator pump 4. Tighten: 8. Install: adjusting screw "3". • Bolt (carburetor joint) "1" • Throttle position sensor lead cou- b. Check that the link lever "4" has pler "1" Bolt (carburetor joint): free play "b" by pushing lightly on •...

  • Page 105: Air Indictoin System

    AIR INDICTOIN SYSTEM AIR INDICTOIN SYSTEM REMOVING THE AIR INDUCTION SYSTEM 7 Nm (0.7 m kg, 5.1 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) 4 Nm (0.4 m kg, 2.9 ft lb) Order Part name Q'ty Remarks Bracket Air cut-off valve assembly Air induction hose (air cut-off valve - front of cyl-...

  • Page 106: Air Indictoin System

    AIR INDICTOIN SYSTEM CHECKING THE AIR INDUCTION SYSTEM 1. Inspect: • Air induction hose → Crack/damage Replace. • Air induction pipe → Crack/damage Replace. 2. Check: • Operation of air cut valve From air filter Pass air through the pipe and To cylinder head (exhaust check the air cut valve for opera- port)

  • Page 107: Camshafts

    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 in the CHAPTER 3. Air cut-off valve assembly Refer to "AIR INDUCTION SYSTEM" section. Spark plug Cylinder head breather hose Bolt (cylinder head cover) Cylinder head cover...
  • Page 108 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. Camshaft cap Refer to removal section.
  • Page 109 CAMSHAFTS REMOVING THE CAMSHAFT Cam lobes length: 1. Remove: Intake "a": • Timing mark accessing screw "1" 29.65–29.75 mm • Crankshaft end accessing screw (1.1673–1.1713 in) "2" <Limit>: 29.55 mm (1.1634 in) Intake "b": 22.45–22.55 mm 4. Remove: (0.8839–0.8878 in) •...
  • Page 110 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"...
  • Page 111 Apply the sealant on the cylinder 10 Nm (1.0 m•kg, 7.2 head cover gasket. d. Install the clips, camshaft caps "4" ft•lb) and bolts (camshaft cap) "5". YAMAHA Bond No. 1215 Bolt (camshaft cap): ® (ThreeBond No. 1215): 10 Nm (1.0 m•kg, 7.2 90890-85505 ft•lb)

  • Page 112: Cylinder Head

    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 in the CHAPTER 3. Refer to "EXHAUST PIPE AND SILENCER" Exhaust pipe and silencer section in the CHAPTER 3.
  • Page 113 CYLINDER HEAD CHECKING THE CYLINDER HEAD • Cylinder head "4" • Union bolt (M8) "3" 1. Eliminate: Union bolt (M8): • Carbon deposits (from the com- While pulling up the timing chain, in- 18 Nm (1.8 m•kg, 13 bustion chambers) stall the timing chain guide (exhaust ft•lb) Use a rounded scraper.

  • Page 114: Valves And Valve Springs

    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.
  • Page 115 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.
  • Page 116 VALVES AND VALVE SPRINGS • Margin thickness "a" → Out of specification Replace. Margin thickness: Intake: 0.8 mm (0.0315 in) Exhaust: 0.7 mm (0.0276 in) c. Install the valve into the cylinder head. Measurement steps: d. Turn the valve until the valve face a.
  • Page 117 VALVES AND VALVE SPRINGS INSTALLING THE VALVES 1. Apply: Hitting the valve tip with excessive • Molybdenum disulfide oil force could damage the valve. Onto the valve stem and valve stem seal. 2. Install: • Valve "1" • Valve spring seat "2" 2.

  • Page 118: Cylinder And Piston

    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 Piston pin clip Refer to removal section. Piston pin Refer to removal section. Piston Refer to removal section.
  • Page 119 CYLINDER AND PISTON REMOVING THE PISTON AND • Piston-to-cylinder clearance Piston-to-cylinder clear- PISTON RING ance: 1. Remove: 0.030–0.055 mm Measurement steps: • Piston pin clip "1" (0.0012–0.0022 in) a. Measure the cylinder bore "C" • Piston pin "2" <Limit>:0.1 mm (0.004 with a cylinder bore gauge.
  • Page 120 CYLINDER AND PISTON 3. Measure: • Ring end gap → Out of specification Replace. You cannot measure the end gap on the expander spacer of the oil control ring. If the oil control ring rails show excessive gap, replace all three rings. c.
  • Page 121 CYLINDER AND PISTON 3. Install: • Cylinder gasket "1" • Cylinder "2" Install the cylinder with one hand while compressing the piston rings with the other hand. • Pass the timing chain "3" through the timing chain cavity. • Be careful not to damage the tim- ing chain guide "4"...

  • Page 122: Clutch

    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 Clutch spring Pressure plate Push rod 1...
  • Page 123 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 5-29...
  • Page 124 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"...
  • Page 125 CLUTCH • Push rod 2 "1" • Ball "2" • Push rod 1 "3" Apply the engine oil on the push rod 1, 2 and ball. 2. Install: 5. Install: • Lock washer "1" • Friction plate 1 "1" • Nut (clutch boss) "2" •...
  • Page 126 CLUTCH Tighten the bolts in stage, using a crisscross pattern. 5-32...

  • Page 127: Oil Filter Element And Water Pump

    OIL FILTER ELEMENT AND WATER PUMP OIL FILTER ELEMENT AND WATER PUMP REMOVING THE OIL FILTER ELEMENT AND WATER PUMP Order Part name Q'ty Remarks Refer to "CHANGING THE ENGINE OIL" Drain the engine oil. section in the CHAPTER 3. Refer to "CHANGING THE COOLANT"...
  • Page 128 OIL FILTER ELEMENT AND WATER PUMP Order Part name Q'ty Remarks Washer Refer to removal section. Impeller shaft Refer to removal section. Oil seal Refer to removal section. Bearing Refer to removal section. 5-34...
  • Page 129 OIL FILTER ELEMENT AND WATER PUMP REMOVING THE IMPELLER SHAFT • Apply the lithium soap base grease 1. Remove: on the oil seal lip. • Impeller "1" • Install the oil seal with its manufac- • Washer "2" ture's marks or numbers facing the •...
  • Page 130 OIL FILTER ELEMENT AND WATER PUMP INSTALLING THE WATER PUMP HOUSING 1. Install: • Dowel pin "1" • O-ring "2" Apply the lithium soap base grease on the O-ring. INSTALLING THE RIGHT CRANKCASE COVER 1. Install: • Dowel pin "1" •...

  • Page 131: Balancer

    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. Refer to "AC MAGNETO AND STARTER Stator CLUTCH" section. Nut (primary drive gear) Refer to removal section.
  • Page 132 BALANCER REMOVING THE BALANCER CHECKING THE BALANCER 1. Straighten the lock washer tab. SHAFT 2. Loosen: 1. Inspect: • Nut (primary drive gear) "1" • Balancer shaft → • Nut (balancer shaft driven gear) Cracks/damage Replace. "2" Place an aluminum plate "a" between 4.

  • Page 133: Oil Pump

    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 Outer rotor 2 Circlip Inner rotor 2...
  • Page 134 OIL PUMP REMOVING THE OIL TANK Order Part name Q'ty Remarks Refer to "CHANGING THE ENGINE OIL" Drain the engine oil. section in the CHAPTER 3. Oil hose 2 Oil hose 1 Dowel pin Oil tank breather hose Oil tank Oil strainer 5-40...
  • Page 135 OIL PUMP CHECKING THE OIL PUMP 1. Inspect: • Oil pump drive gear "1" • Oil pump drive shaft "2" • Rotor housing "3" • Oil pump cover "4" → Cracks/wear/damage Replace. INSTALLING THE OIL PUMP 4. Install: 1. Install: •...

  • Page 136: Kick Shaft And Shift Shaft

    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...
  • Page 137 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. 5-43...

  • Page 138: Kick Shaft And Shift Shaft

    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. →...
  • Page 139 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" •...
  • Page 140 KICK SHAFT AND SHIFT SHAFT INSTALLING THE KICK IDLE GEAR 1. Install: • Kick idle gear "1" • Washer "2" • Circlip "3" • Apply the engine oil on the kick idle gear inner circumference. • Install the kick idle gear with its de- pressed side "a"...

  • Page 141: Ac Magneto And Starter Clutch

    AC MAGNETO AND STARTER CLUTCH AC MAGNETO AND STARTER CLUTCH REMOVING THE AC MAGNETO AND STARTER CLUTCH Order Part name Q'ty Remarks Refer to "CHANGING THE ENGINE OIL" Drain the engine oil. section in the CHAPTER 3. Refer to "SEAT, FUEL TANK AND SIDE Seat and fuel tank COVERS"...
  • Page 142 AC MAGNETO AND STARTER CLUTCH Order Part name Q'ty Remarks Bearing Washer Idle gear plate Idle gear Holder Pickup coil Stator Tighten the rotor nut to 65 Nm (6.5 m•kg, 47 ft•lb), loosen and retighten the rotor nut to 65 Nm (6.5 m•kg, 47 ft•lb). 5-48...
  • Page 143 AC MAGNETO AND STARTER CLUTCH REMOVING THE ROTOR 1. Remove: a. Install the starter clutch drive gear • Nut (rotor) "1" "1" onto the starter clutch "2" and • Washer hold the starter clutch. Use the sheave holder "2". b. When turning the starter clutch Sheave holder: drive gear counterclockwise "B", YS-1880-A/90890-...
  • Page 144 Apply the sealant to the grommet of the AC magneto lead. YAMAHA Bond No. 1215 9. Install: ® (ThreeBond No. 1215): • Washer (rotor) 90890-85505 •...
  • Page 145 AC MAGNETO AND STARTER CLUTCH • Bolt [crankcase cover (left)] "3" Bolt [crankcase cover (left)]: 12 Nm (1.2 m•kg, 8.7 ft•lb) Tighten the bolts in stage, using a 14. Install: crisscross pattern. • Shift pedal "1" • Bolt (shift pedal) Bolt (shift pedal): 12 Nm (1.2 m•kg, 8.7 ft•lb)

  • Page 146: Engine Removal

    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 "CHANGING THE ENGINE OIL" Drain the engine oil. section in the CHAPTER 3. Refer to "SEAT, FUEL TANK AND SIDE Seat and fuel tank COVERS"...
  • Page 147 ENGINE REMOVAL Order Part name Q'ty Remarks Negative battery lead Disconnect at the engine side. 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...
  • Page 148 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.
  • Page 149 ENGINE REMOVAL Tighten the nut while applying the rear brake. 3. Bend the lock washer tab to lock the nut. 4. Install: • Drive chain sprocket guide "1" • Drive chain sprocket cover "2" • Screw (drive chain sprocket cov- er) "3"...

  • Page 150: Crankcase And Crankshaft

    CRANKCASE AND CRANKSHAFT CRANKCASE AND CRANKSHAFT REMOVING THE CRANKSHAFT Order Part name Q'ty Remarks Engie Refer to "ENGINE REMOVAL" section. Piston Refer to "CYLINDER AND PISTON" section. Refer to "KICK SHAFT AND SHIFT SHAFT" Kick shaft assembly section. Refer to "KICK SHAFT AND SHIFT SHAFT" Segment section.
  • Page 151 CRANKCASE AND CRANKSHAFT Order Part name Q'ty Remarks Right crankcase Refer to removal section. Left crankcase Refer to removal section. Oil strainer Crankshaft Refer to removal section. 5-57...
  • Page 152 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. 5-58...
  • Page 153 CRANKCASE AND CRANKSHAFT DISASSEMBLING THE c. Remove the dowel pins and O- CHECKING THE CRANKCASE CRANKCASE ring. 1. Inspect: 1. Separate: • Contacting surface "a" → • Right crankcase Scratches Replace. REMOVING THE CRANKSHAFT • Left crankcase • Engine mounting boss "b", crank- 1.
  • Page 154 Operate the installing tool un- On the right crankcase "1". • Bearing til the crankshaft bottoms against • Bearing stopper the bearing. YAMAHA Bond No. 1215 • Bolt (bearing stopper) • Before installing the crankshaft, ® (ThreeBond No.1215): clean the contacting surface of...
  • Page 155 CRANKCASE AND CRANKSHAFT Apply the lithium soap base grease on the Orings. 5. Install: • Dowel pin "1" • O-ring "2" • Right crankcase To left crankcase. 8. Install: • Timing chain "1" • Timing chain guide (intake side) • Apply the lithium soap base grease "2"...

  • Page 156: Transmission, Shift Cam And Shift Fork

    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.
  • Page 157 TRANSMISSION, SHIFT CAM AND SHIFT FORK REMOVING THE TRANSMISSION 1. Remove: Apply the molybdenum disulfide oil • Main axle "1" on the inner and end surface of the • Drive axle "2" idler gear and on the inner surface of •...
  • Page 158 TRANSMISSION, SHIFT CAM AND SHIFT FORK 6. Install: 4. Install: • Transmission assembly "1" • Collar "1" To left crankcase "2". • Apply the lithium soap base grease Apply the engine oil on the bearings on the oil seal lip. and guide bars.

  • Page 159: Front Wheel And Rear Wheel

    FRONT WHEEL AND REAR WHEEL CHASSIS FRONT WHEEL AND REAR WHEEL REMOVING THE FRONT WHEEL 21 Nm (2.1 m kg, 15 ft lb) 21 Nm (2.1 m kg, 15 ft lb) 90 Nm (9.0 m kg, 65 ft lb) 12 Nm (1.2 m kg, 8.7 ft lb) Order Part name Q'ty...
  • Page 160 FRONT WHEEL AND REAR WHEEL REMOVING THE REAR WHEEL 14 Nm (1.4 m kg, 10 ft lb) 125 Nm (12.5 m kg, 90 ft lb) 19 Nm (1.9 m kg, 13 ft lb) 50 Nm (5.0 m kg, 36 ft lb) 19 Nm (1.9 m kg, 13 ft lb) Order Part name...
  • Page 161 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 •...
  • Page 162 FRONT WHEEL AND REAR WHEEL • Bolt (brake disc) "2" Bolt (brake disc): 12 Nm (1.2 m•kg, 8.7 ft•lb) Tighten the bolts in stage, using a crisscross pattern. 6. Install: INSTALLING THE REAR WHEEL 3. Install: • Wheel axle "1" 1.
  • Page 163 FRONT WHEEL AND REAR WHEEL 2. Install: • Brake disc "1" • Bolt (brake disc) "2" Bolt (brake disc): 14 Nm (1.4 m•kg, 10 ft•lb) 6. Install: 10. Tighten: Tighten the bolts in stage, using a • Drive chain "1" •...

  • Page 164: Front Brake And Rear Brake

    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) Brake hose holder (brake caliper) Union bolt...

  • Page 165: Front Brake And Rear Brake

    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.
  • Page 166 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.
  • Page 167 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 Brake master cylinder boot Circlip Use a long nose circlip pliers. Washer Push rod Brake master cylinder kit...
  • Page 168 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.
  • Page 169 FRONT BRAKE AND REAR BRAKE HANDLING NOTE Apply the brake fluid on the piston wall. • All internal parts should be cleaned in new brake fluid only. • Internal parts should be lubricat- • Install the piston with its shallow ed with brake fluid when in- depressed side "a"...
  • Page 170 FRONT BRAKE AND REAR BRAKE • Pad pin plug "4" • Pad pin plug "4" Pad pin plug: Pad pin plug: 3 Nm (0.3 m•kg, 2.2 3 Nm (0.3 m•kg, 2.2 ft•lb) ft•lb) A. Front B. Rear 4. Install: • Brake master cylinder kit "1" •...
  • Page 171 FRONT BRAKE AND REAR BRAKE 2. Install: 2. Install: INSTALLING THE FRONT BRAKE • Brake lever "1" • Brake master cylinder "1" HOSE • Bolt (brake lever) "2" • Bolt (brake master cylinder) "2" 1. Install: • Copper washer "1" Bolt (brake lever): Bolt (brake master cylin- •...
  • Page 172 FRONT BRAKE AND REAR BRAKE • Nut (brake hose holder) "2" INSTALLING THE REAR BRAKE HOSE Nut (brake hose holder): 1. Install: 7 Nm (0.7 m•kg, 5.1 ft • Copper washer "1" •lb) • Brake hose "2" • Union bolt "3" Align the top "a"...
  • Page 173 FRONT BRAKE AND REAR BRAKE 3. Inspect: • Brake fluid level → Fluid at lower level Fill up. Refer to "CHECKING THE BRAKE FLUID LEVEL" section in the CHAPTER 3. 4. Install: • Reservoir float (front brake) • Diaphragm • Brake master cylinder cap "1" •...

  • Page 174: Front Fork

    FRONT FORK FRONT FORK REMOVING THE FRONT FORK 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 Front wheel WHEEL" section. Refer to "FRONT BRAKE AND REAR Front brake caliper BRAKE"...
  • Page 175 FRONT FORK DISASSEMBLING THE FRONT FORK Order Part name Q'ty Remarks Front fork cap bolt Refer to removal section. Fork spring Drain the fork oil. Dust seal Refer to removal section. Stopper ring Refer to removal section. Inner tube Refer to removal section. Outer tube Piston metal Slide metal...
  • Page 176 FRONT FORK HANDLING NOTE REMOVING THE INNER TUBE 1. Remove: The front fork with a built-in piston • Dust seal "1" Support the machine securely so rod has a very sophisticated inter- • Stopper ring "2" there is no danger of it falling over. nal construction and is particularly Using slotted-head screwdriver.
  • Page 177 FRONT FORK The bending value is shown by one half of the dial gauge reading. Do not attempt to straighten a bent inner tube as this may dangerous- ly weaken the tube. 3. Install: 6. Install: • Copper washer "1" •...
  • Page 178 FRONT FORK 9. Install: 12. Install: 17. Fill: • Slide metal "1" • Dust seal "1" • Front fork oil • Oil seal washer "2" Until outer tube top surface with To outer tube slot. recom-mended fork oil once Apply the lithium soap base grease more.
  • Page 179 FRONT FORK To outer tube. Be sure to install the spring guide "2" Temporarily tighten the cap bolt. when checking the oil level. Never fail to make the oil level ad- justment between the maximum and minimum level and always ad- 23.
  • Page 180 FRONT FORK 4. Tighten: • Pinch bolt (upper bracket) "1" Pinch bolt (upper brack- et): 21 Nm (2.1 m•kg, 15 ft•lb) • Pinch bolt (lower bracket) "2" 7. Install: Pinch bolt (lower brack- • Protector "1" et): • Bolt (protector) "2" 21 Nm (2.1 m•kg, 15 Bolt (protector): ft•lb)

  • Page 181: Handlebar

    HANDLEBAR HANDLEBAR REMOVING THE HANDLEBAR Order Part name Q'ty Remarks Headlight Hot starter cable Disconnect at the lever side. Hot starter lever holder Clutch cable Disconnect at the lever side. Clutch lever holder Disconnect the clutch switch lead. Engine stop switch Disconnect the engine stop switch lead.
  • Page 182 HANDLEBAR REMOVING THE BRAKE MASTER CYLINDER • Install the handlebar lower holder 1. Remove: with its side having the greater dis- • Brake master cylinder bracket "1" tance "a" from the mounting bolt • Brake master cylinder "2" center facing forward. •...
  • Page 183 HANDLEBAR • Screw (throttle cable cap) "2" 5. Install: • Right grip "1" Screw (throttle cable • Collar "2" cap): Apply the adhesive on the tube 4 Nm (0.4 m•kg, 2.9 guide "3". ft•lb) • Before applying the adhesive, wipe off grease or oil on the tube guide After tightening the screws, check surface "a"...
  • Page 184 HANDLEBAR Apply the lithium soap base grease on the clutch cable end and hot start- er cable end. 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"...

  • Page 185: Steering

    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".
  • Page 186 STEERING Order Part name Q'ty Remarks Bearing race cover Upper bearing Lower bearing Refer to removal section. Bearing race Refer to removal section. 6-28...
  • Page 187 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.
  • Page 188 STEERING 11. Adjust: • Front fork top end "a" Front fork top end (stan- dard) "a": 5 mm (0.20 in) 7. Install: 14. Install: • Front fork "1" • Holder "1" • Upper bracket "2" Holder: • Main switch "3" 13 Nm (1.3 m•kg, 9.4 •...

  • Page 189: Swingarm

    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"...
  • Page 190 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. 6-32...
  • Page 191 SWINGARM → HANDLING NOTE 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: CHECKING THE CONNECTING • Bearing "1" Remove with a slotted-head screw- •...
  • Page 192 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.
  • Page 193 SWINGARM • Nut (drive chain support) "4" Nut (drive chain sup- port): 7 Nm (0.7 m•kg, 5.1 ft•lb) • Bolt {drive chain support cover[L = 10 mm (0.39 in)]} "5" 11. Tighten: Bolt (drive chain support • Nut (relay arm) "1" cover): 7 Nm (0.7 m•kg, 5.1 Nut (relay arm):...

  • Page 194: Absorber

    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 and side cover COVERS"...
  • Page 195 REAR SHOCK ABSORBER Order Part name Q'ty Remarks CDI unit coupler Plastic band Clamp (air filter joint) Only loosening. Rear frame Bolt (rear shock absorber-relay arm) Hold the swingarm. Bolt (rear shock absorber-frame) Rear shock absorber Locknut Only loosening. Adjuster Only loosening.
  • Page 196 To dispose of a damaged or worn- ABSORBER out rear shock absorber, take the After installing the stopper ring, push 1. Inspect: unit to your Yamaha dealer for this back the bearing until it contacts the • Damper rod "1" disposal procedure. stopper ring.
  • Page 197 REAR SHOCK ABSORBER Apply the molybdenum disulfide grease on the bolt. 3. Install: INSTALLING THE REAR SHOCK • Lower bearing "1" ABSORBER 1. Install: • Dust seal "1" Install the bearing by pressing it on • O-ring "2" 5. Install: the side having the manufacture's •...
  • Page 198 REAR SHOCK ABSORBER 8. Install: • Plastic band • Taillight coupler • Locking tie 6-40...

  • Page 199: Components And Wiring Diagram

    ELECTRICAL COMPONENTS AND WIRING DIAGRAM ELECTRICAL ELECTRICAL COMPONENTS AND WIRING DIAGRAM ELECTRICAL COMPONENTS Headlight 12. Taillight Multi-function display 13. Neutral switch Engine stop switch 14. Starter motor Clutch switch 15. AC magneto Diode 16. Rectifier/regulator Starter relay diode 17. Ignition coil Throttle position sensor 18.
  • Page 200 ELECTRICAL COMPONENTS AND WIRING DIAGRAM WIRING DIAGRAM Headlight COLOR CODE Multi-function display Black Engine stop switch Brown Clutch switch Chocolate Diode Dark green Starter relay diode Green Throttle position sensor Gray Starter relay Blue Fuse Orange 10. Starting circuit cut-off relay 11.

  • Page 201: Ignition System

    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. → *1 Check fuse. No good Replace fuse and check wire harness.
  • Page 202 IGNITION SYSTEM SPARK GAP TEST Use 12 V battery. Result 1. Disconnect the ignition coil from Conductive (while the → Battery (+) lead Red/Black lead spark plug. engine stop switch is "1" 2. Remove the ignition coil cap. pushed) → Battery (-) lead Black lead "2"...

  • Page 203: Electric Starting System

    ELECTRIC STARTING SYSTEM 4. Inspect: CHECKING THE CDI UNIT • Sealed portion of ignition coil "a" Check all electrical components. If no • Spark plug terminal pin "b" fault is found, replace the CDI unit. • Threaded portion of spark plug "c" Then check the electrical compo- →...
  • Page 204 ELECTRIC STARTING SYSTEM INSPECTION STEPS If the starter motor will not operate, use the following inspection steps. → *1 Check fuse. No good Replace fuse and check wire harness. ↓ → *2 Check battery. No good Recharge or replace. ↓ →...
  • Page 205 ELECTRIC STARTING SYSTEM CHECKING THE COUPLERS AND LEADS CONNECTION 1. Check: • Couplers and leads connection Rust/dust/looseness/short-circuit → Repair or replace. CHECKING THE STARTER MOTOR OPERATION CHECKING THE STARTER RELAY CHECKING THE DIODE 1. Connect the positive battery ter- 1. Remove: 1.
  • Page 206 ELECTRIC STARTING SYSTEM 2. Inspect: • Rubber part "a" → Tears/damage Replace.
  • Page 207 ELECTRIC STARTING SYSTEM REMOVING THE STARTER MOTOR Order Part name Q'ty Remarks Refer to "EXHAUST PIPE AND SILENCER" Exhaust pipe section in the CHAPTER 3. Starter motor...
  • Page 208 ELECTRIC STARTING SYSTEM DISASSEMBLING THE STARTER MOTOR Order Part name Q'ty Remarks Starter motor front cover Washer (starter motor front cover) Gasket Starter motor yoke Armature assembly Starter motor rear cover Brush Brush spring 7-10...
  • Page 209 ELECTRIC STARTING SYSTEM CHECKING AND REPAIRING THE Armature assembly: STARTER MOTOR Commutator resis- 1. Check: tance "1": • Commutator Ω 0.0189–0.0231 → Dirt Clean with 600 grit sandpa- 20 °C (68 °F) per. Insulation resistance 2. Measure: "2": • Commutator diameter "a" Ω...
  • Page 210 ELECTRIC STARTING SYSTEM 5. Install: • Gasket • Bolt "1" • O-ring "2" Apply the lithium soap base grease on the O-ring. 7-12...

  • Page 211: Charging System

    CHARGING SYSTEM CHARGING SYSTEM INSPECTION STEPS If the battery is not charged, use the following inspection steps. → *1 Check fuse. No good Replace fuse and check wire harness. ↓ → *2 Check battery. No good Recharge or replace. ↓ →...
  • Page 212 CHARGING SYSTEM CHECKING THE COUPLERS AND LEADS CONNECTION 1. Check: • Couplers and leads connection Rust/dust/looseness/short-circuit → Repair or replace. CHECKING THE CHARGING VOLTAGE 1. Start the engine. 2. Inspect: • Charging voltage → Out of specification If no failure is found in checking the source coil resistance, replace the rectifi- er/regulator.

  • Page 213: Throttle Position Sensor System

    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.
  • Page 214 THROTTLE POSITION SENSOR SYSTEM HANDLING NOTE • Throttle position sensor coil vari- • Temporarily tighten the screw able resistance (throttle position sensor). Check that the resistance in in- Do not loosen the screw (throttle creased as the throttle grip is position sensor) "1"...
  • Page 215 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.

  • Page 216: Lighting System

    LIGHTING SYSTEM LIGHTING SYSTEM INSPECTION STEPS Refer to the following flow chart when inspecting the lighting system for possible problems. → Check the bulb and bulb socket. No good Replace the bulb and/or bulb socket. ↓ → Check the taillight (LEDs). No good Replace the taillight assembly.
  • Page 217 LIGHTING SYSTEM CHECKING THE TAILLIGHT • Out-put voltage → (LEDs) Out of specification Replace 1. Disconnect the taillight coupler. rectifier/regulator. 2. Connect two jumper leads "1" → Tester (+) lead Yellow lead "1" from the battery terminals to the → Tester (-) lead Black lead "2"...

  • Page 218: Signaling System

    SIGNALING SYSTEM SIGNALING SYSTEM INSPECTION STEPS If the speedometer will not operate, use the following inspection steps. → *1 Check battery. No good Recharge or replace. ↓ → Check each coupler and wire connection. No good Repair or replace. ↓ →...
  • Page 219 SIGNALING SYSTEM CHECKING THE COUPLERS AND LEADS CONNECTION Make sure that a short-circuit does 1. Check: not develop between the terminals • Couplers and leads connection because it may cause damage to Rust/dust/looseness/short-circuit electrical components. → Repair or replace. CHECKING THE MULTI-FUNCTION DISPLAY INPUT VOLTAGE 1.
  • Page 222 PRINTED ON RECYCLED PAPER PRINTED IN JAPAN YAMAHA MOTOR CO., LTD. 2007.08-0.8×1 CR 2500 SHINGAI IWATA SHIZUOKA JAPAN...

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