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Bitte lesen Sie diese Bedienungsanleitung sorgfältig durch, bevor Sie das Fahrzeug in Betrieb nehmen. q Leggere attentamente questo manuale prima di utilizzare questo veicolo. OWNER’S SERVICE MANUAL MANUEL D’ATELIER DU PROPRIETAIRE FAHRER- UND WARTUNGSHANDBUCH MANUALE DI SERVIZIO DEL PROPRIETARIO YZ250 ( Y ) 1P8-28199-34...
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Read this manual carefully before operating this vehicle. This manual should stay with this vehicle if it is sold. Il convient de lire attentivement ce manuel avant la première utilisation du véhicule. Le manuel doit être remis avec le véhicule en cas de vente de ce dernier. Bitte lesen Sie diese Bedienungsanleitung sorgfältig durch, bevor Sie das Fahrzeug in Betrieb nehmen.
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2009 2009 Read this manual carefully before operating this vehicle. Read this manual carefully before operating this vehicle. OWNER’S SERVICE MANUAL OWNER’S SERVICE MANUAL YZ250(Y) YZ250(Y) 1P8-28199-34-E0 1P8-28199-34-E0...
• GASOLINE CAN CAUSE INJURY. Congratulations on your purchase of could result in death or serious in- If you should swallow some gaso- a Yamaha YZ series. This model is jury. line, inhale excess gasoline vapors, the culmination of Yamaha's vast ex-...
HOW TO USE THIS MANUAL FINDING THE REQUIRED PAGE 1. This manual consists of seven chapters; "General Information", "Specifications", "Regular inspec- tion and adjustments", "Engine", "Chassis", "Electrical" and "Tun- ing" 2. The table of contents is at the be- ginning of the manual. Look over the general layout of the book be- fore finding then required chapter and item.
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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.
CONTENTS CHAPTER 1 CHAPTER 3 CHAPTER 5 GENERAL REGULAR CHASSIS INFORMATION INSPECTION AND ADJUSTMENTS FRONT WHEEL AND REAR WHEEL ....5-1 DESCRIPTION ....1-1 FRONT BRAKE AND MACHINE MAINTENANCE REAR BRAKE ....5-6 IDENTIFICATION ..... 1-2 INTERVALS...... 3-1 FRONT FORK....5-16 INCLUDED PARTS ..1-2 PRE-OPERATION HANDLEBAR....5-24 IMPORTANT...
DESCRIPTION GENERAL INFORMATION DESCRIPTION Clutch lever 14. Fuel cock Engine stop switch 15. Starter knob Front brake lever 16. Drive chain Throttle grip 17. Air filter Radiator cap 18. Shift pedal Fuel tank cap 19. Front fork Kickstarter crank Fuel tank Radiator 10.
End of each hose 5. Keep away from fire. ALL REPLACEMENT PARTS VALVE JOINT 1. We recommend to use Yamaha This valve joint "1" prevents fuel from genuine parts for all replace- flowing out and is installed to the fuel ments.
CHECKING OF CONNECTION 7. Check for continuity with a tester. assembly and adjustment. CIRCLIPS 1. All circlips should be inspected GASKETS, OIL SEALS AND O- carefully before reassembly. Al- • If there in no continuity, clean the RINGS ways replace piston pin clips after terminals.
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 Radiator cap tester These tools are used for checking YU-24460-01, 90890-01325 the cooling system. Radiator cap tester adapter YU-33984, 90890-01352 Steering nut wrench This tool is used when tighten the YU-33975, 90890-01403 steering ring nut to specification.
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Ignition checker nents. 90890-06754 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 KICKSTARTER CRANK FUEL COCK Rotate the kickstarter crank "1" away The fuel cock supplies fuel from the ENGINE STOP SWITCH from the engine. Push the starter tank to carburetor and also filters the The engine stop switch "1" is located down lightly with your foot until the fuel.
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STARTING AND BREAK-IN ally takes about one or two min- semble the top end. utes. 8. Drain the break-in oil-fuel mixture Never mix two types of oil in the 5. The engine is warmed up when it from the fuel tank and refill with same batch;...
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 STORAGE If your machine is to be stored for 60 CLEANING days or more, some preventive mea- Frequent cleaning of your machine sures must be taken to avoid deterio- will enhance its appearance, maintain ration.
GENERAL SPECIFICATIONS SPECIFICATIONS GENERAL SPECIFICATIONS Model name: YZ250Y (USA, CDN, AUS, NZ) YZ250 (EUROPE, ZA) Model code number: 1P8H (USA, CDN) 1P8J (EUROPE) 1P8L (AUS, NZ, ZA) Dimensions: USA, AUS, NZ, ZA EUROPE, CDN Overall length 2,178 mm (85.7 in) 2,184 mm (86.0 in)
MAINTENANCE SPECIFICATIONS Transmission: Primary reduction system Gear Primary reduction ratio 63/21 (3.000) Secondary reduction system Chain drive Secondary reduction ratio 50/14 (3.571) Transmission type Constant mesh, 5-speed Operation Left foot operation Gear ratio: 27/14 (1.929) 23/15 (1.533) 23/18 (1.278) 24/22 (1.091) 20/21 (0.952) Chassis: USA, ZA, AUS, NZ...
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MAINTENANCE SPECIFICATIONS Item Standard Limit Cylinder: Bore size 66.400–66.414 mm (2.6142–2.6147 in) 66.5 mm (2.1618 in) Taper limit ---- 0.05 mm (0.0020 in) Out of round limit ---- 0.01 mm (0.0004 in) Piston: Piston size/ 66.352–66.367 mm (2.6120–2.6129 in) ---- Measuring point "H"...
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MAINTENANCE SPECIFICATIONS Item Standard Limit Clutch: Friction plate thickness 2.9–3.1 mm (0.114–0.122 in) 2.8 mm (0.110 Quantity ---- Clutch plate thickness 1.5–1.7 mm (0.059–0.067 in) ---- Quantity ---- Warp limit ---- 0.2 mm (0.008 Clutch spring free length 50.0 mm (1.969 in) 48.0 mm (1.890 in) Quantity...
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MAINTENANCE SPECIFICATIONS Item Standard Limit Cooling: Radiator core size: ---- Width 107.8 mm (4.24 in) ---- Height 240 mm (9.45 in) ---- Thickness 32 mm (1.26 in) ---- Radiator cap opening pressure 95–125 kPa (0.95–1.25 kg/cm , 13.5–17.8 psi) ---- Radiator capacity (total) 0.63 L (0.55 Imp qt, 0.67 US qt) ----...
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MAINTENANCE SPECIFICATIONS Item Standard Limit Swingarm: Swingarm free play limit ---- 1.0 mm (0.04 Side clearance ---- 0.2–0.9 mm (0.008–0.035 Wheel: Front wheel type Spoke wheel ---- Rear wheel type Spoke wheel ---- Front rim size/material 21 × 1.60/Aluminum ---- Rear rim size/material 19 ×...
0.18 mm (0.007 in) ---- Advancer type Electrical ---- CDI: Magneto-model (stator)/Manufacturer 5CU-20/YAMAHA ---- Charging coil 1 resistance (color) 720–1,080 Ωat 20 °C (68 °F) (Black- ---- Black/Red) Charging coil 2 resistance (color) 44–66 Ωat 20 °C (68 °F) (Green/Blue-...
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TIGHTENING TORQUES Tightening torque Part to be tightened Thread size Q'ty m•kg ft•lb Radiator M6 × 1.0 Radiator panel M6 × 1.0 Radiator hose clamp M6 × 1.0 Air filter element M6 × 1.0 Carburetor joint M6 × 1.0 Air filter case M6 ×...
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TIGHTENING TORQUES CHASSIS △ - marked portion shall be checked for torque tightening after break-in or before each race. Tightening torque Part to be tightened Thread size Q'ty m•kg ft•lb Upper bracket and outer tube M8 × 1.25 △ Lower bracket and outer tube M8 ×...
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TIGHTENING TORQUES Tightening torque Part to be tightened Thread size Q'ty m•kg ft•lb Nipple (spoke) — △ Disc cover and rear brake caliper M6 × 1.0 △ Protector and rear brake caliper M6 × 1.0 △ Drive chain puller adjust bolt and locknut M8 ×...
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TIGHTENING TORQUES ELECTRICAL Tightening torque Part to be tightened Thread size Q'ty m•kg ft•lb Stator M6 × 1.0 Rotor M12 × 1.25 Ignition coil M6 × 1.0 Neutral switch (Except for USA and CDN) M5 × 0.8 2-11...
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TIGHTENING TORQUES GENERAL TORQUE TORQUE SPECIFI- SPECIFICATIONS CATION This chart specifies torque for stan- (Nut) (Bolt) 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 "ENGINE STOP" button lead Pass the clutch cable on the out- Clamp the "ENGINE STOP" but- Throttle cable side of the throttle cable and ton lead to the frame. Tighten Clutch cable "ENGINE STOP" button lead. the clamp so that the "ENGINE Clamp Align the throttle cable locating...
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CABLE ROUTING DIAGRAM Clamp the throttle cable and wireharness to the frame. Pass the clutch cable in front of the center of the cylinder head tightening nut. Pass the air vent hose, overflow hose and crankcase breather hose between the frame and connecting rod.
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CABLE ROUTING DIAGRAM Ignition coil lead Clamp the ignition coil lead to Do not allow the neutral switch Clamp the frame at its locating tape. lead to slacken except over the CDI magneto lead Clamp it in front of the radiator radiator hose.
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CABLE ROUTING DIAGRAM Pass the radiator breather hose outside the engine bracket and inside the down tube. Then pass the radiator breather hose inside the CDI magneto lead. Clamp the CDI magneto lead, radiator breather hose, YPVS breather hose and neutral switch lead (except for USA and CDN) to the frame.
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CABLE ROUTING DIAGRAM Clamp Clamp the wireharness protect- Bring the connector cover into Wireharness ing tube to the right engine contact with the coupler. High tension cord bracket. Pass the radiator breather hose CDI unit band Pass the high tension cord to the behind the radiator hose.
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CABLE ROUTING DIAGRAM Install the brake hose so that its Master cylinder Install the brake hose so that its pipe portion directs as shown Brake hose holder pipe portion directs as shown and lightly touches the projec- Brake hose and lightly touches the projec- tion on the caliper.
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CABLE ROUTING DIAGRAM Brake hose Install the brake hose so that its Pass the brake hose in front of Master cylinder pipe portion directs as shown the number plate and through "ENGINE STOP" button lead and lightly touches the projec- 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. After...
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MAINTENANCE INTERVALS After Every Every Every As re- Item break- Remarks race third fifth quired CARBURETOR Inspect, adjust and clean ● ● SPARK PLUG Inspect and clean ● ● Replace ● DRIVE CHAIN Use chain lube. Lubricate, slack, alignment Chain slack: 48–58 mm (1.9–2.3 in) ●...
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Retighten sprocket bolt ● ● Inspect bearings ● Replace bearings ● Lubricate Lithium base grease ● THROTTLE, CONTROL CABLE Check routing and connection ● ● Lubricate Yamaha cable lube or SAE 10W-30 ● ● motor oil...
PRE-OPERATION INSPECTION AND MAINTENANCE PRE-OPERATION INSPECTION AND MAINTENANCE Before riding for break-in operation, practice or a race, 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.
ENGINE ENGINE gine. 2. Remove: CHECKING THE COOLANT LEVEL • When coolant splashes to your • Coolant drain bolt "1" eye. Thoroughly wash your eye with Do not remove the radiator cap water and see your doctor. "1", drain bolt and hoses when the •...
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ENGINE 2. Apply the specified pressure. ADJUSTING THE CLUTCH CABLE ADJUSTING THE THROTTLE FREE PLAY CABLE FREE PLAY Radiator cap opening 1. Check: 1. Check: pressure: • Clutch lever free play "a" • Throttle grip free play "a" 95–125 kPa (0.95–1.25 Out of specification →...
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ENGINE • Do not twist the element when squeezing the element. • Leaving too much of solvent in the element may result in poor starting. 3. Inspect: 2. Apply: CHECKING THE TRANSMISSION • Air filter element • Lithium soap base grease OIL LEVEL Damage →...
CHASSIS CHANGING THE TRANSMISSION b. Turn out the pilot air screw by the factory-set number of turns. 1. Start the engine and warm it up for several minutes and wait for To optimize the fuel flow at a smaller five minute. throttle opening, each machine's pilot 2.
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CHASSIS f. Pull the lever in or push down on Brake lever position adjustment ment, make sure that the rear the pedal. Hold the lever or pedal steps: brake does not drag. in position. a. Loosen the locknut "1". g. Loosen the bleed screw and allow b.
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CHASSIS d. Remove the pad pin and brake pads "4". Install the pad pin plug "10". b. Loosen the pad pin "3". c. Remove the rear wheel "4" and Pad pin plug: e. Connect the transparent hose "5" brake caliper "5". 3 Nm (0.3 m•kg, 2.2 to the bleed screw "6"...
CHASSIS 4. Check: eral times to find the tightest point. e. Tighten the locknuts. • Drive chain stiffness "a" Check and/or adjust the drive chain Locknut: Clean and oil the drive chain and slack with the rear wheel in this "tight 19 Nm (1.9 m•kg, 13 hold as illustrated.
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CHASSIS 1. Elevate the front wheel by placing Damage/oil leakage → Replace. a suitable stand under the engine. Always adjust each front fork to 2. Remove the air bleed screw "1" the same setting. Uneven adjust- and release the internal pressure ment can cause poor handling and from the front fork.
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CHASSIS • Rear frame (lower) ADJUSTING THE REAR SHOCK 4. Adjust: ABSORBER LOW COMPRESSION • Spring preload Rear frame (lower): DAMPING FORCE 29 Nm (2.9 m•kg, 21 1. Adjust: ft•lb) Adjustment steps: • Low compression damping force a. Loosen the locknut "1". ADJUSTING THE REAR SHOCK By turning the adjuster "1".
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CHASSIS ADJUSTING THE REAR SHOCK Spokes: ABSORBER HIGH COMPRESSION • Check the tire while it is cold. 3 Nm (0.3 m•kg, 2.2 DAMPING FORCE • Loose bead stoppers allow the tire ft•lb) 1. Adjust: to slip off its position on the rim CHECKING THE WHEELS •...
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CHASSIS 4. Adjust: ing bearings. • Steering ring nut h. Install the washer "5", upper bracket "6", washer "7", steering stem nut "8", handlebar "9", han- Steering ring nut adjustment dlebar upper holder "10" and steps: number plate "11". a. Remove the number plate. b.
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CHASSIS LUBRICATION To ensure smooth operation of all Use Yamaha cable lube or components, lubricate your machine equivalent on these areas. during setup, after break-in, and after Use SAE 10W-30 motor oil or every race. suitable chain lubricants. Lubricate the following areas...
ELECTRICAL 7. Adjust: CHECKING THE IGNITION TIMING ELECTRICAL • Ignition timing 1. Remove: CHECKING THE SPARK PLUG • Fuel tank 1. Remove: Refer to "SEAT, FUEL TANK Adjustment steps: • Spark plug AND SIDE COVERS" section in a. Loosen the screws (stator) "1". 2.
SEAT, FUEL TANK AND SIDE COVERS ENGINE This section is intended for those who have basic knowledge and skill concerning the servicing of Yamaha motorcycles (e.g., Yamaha dealers, service engineers, etc.) Those who have little knowledge and skill concerning servicing are request- ed not to undertake inspection, adjustment, disassembly, or reassembly only by reference to this manual.
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SEAT, FUEL TANK AND SIDE COVERS REMOVING THE SIDE COVER 1. Remove: • Bolt (side cover) • Side cover (left and right) "1" Draw the side cover downward to re- move it because its claws "a" are in- serted in the air filter case. REMOVING THE NUMBER PLATE 1.
EXHAUST PIPE AND SILENCER EXHAUST PIPE AND SILENCER REMOVING THE EXHAUST PIPE AND SILENCER 12 Nm (1.2 m kg, 8.7 ft lb) 15 mm (0.59 in) 12 Nm (1.2 m kg, 8.7 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) 14.5 mm (0.57 in) 12 Nm (1.2 m kg, 8.7 ft lb)
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• Fiber "2" 4. Install: • Inner pipe ® Fully apply Quick gasket (Yamaha bond No.1215) or equivalent as shown. Yamaha bond No.1215 ® (Three Bond No.1215): 90890-85505 5. Install: • Bolt (fiber) "1" Bolt (fiber): 10 Nm (1.0 m•kg, 7.2 ft•lb)
RADIATOR RADIATOR REMOVING THE RADIATOR 2 Nm (0.2 m kg, 1.4 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) 10 Nm (1.0 m kg, 7.2 ft lb) 2 Nm (0.2 m kg, 1.4 ft lb) Order Part name...
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RADIATOR HANDLING NOTE • Radiator hose 4 "4" Radiator hose 4: 2 Nm (0.2 m•kg, 1.4 Do not remove the radiator cap ft•lb) when the engine and radiator are hot. Scalding hot fluid and steam Refer to "CABLE ROUTING DIA- may be blown out under pressure, GRAM"...
CARBURETOR AND REED VALVE CARBURETOR AND REED VALVE REMOVING THE CARBURETOR AND REED VALVE 10 Nm (1.0 m kg, 7.2 ft lb) 1 Nm (0.1 m kg, 0.7 ft lb) Order Part name Q'ty Remarks Refer to "SEAT, FUEL TANK AND SIDE Fuel tank COVERS"...
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CARBURETOR AND REED VALVE DISASSEMBLING THE CARBURETOR 4 Nm (0.4 m kg, 2.9 ft lb) Order Part name Q'ty Remarks Mixing chamber top Throttle valve Refer to removal section. Needle holder Jet needle Float chamber Float pin Float Needle valve Main jet Pilot jet Starter plunger...
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CARBURETOR AND REED VALVE HANDLING NOTE Contamination → Clean. • Use a petroleum based solvent for Do not loosen the screw (throttle cleaning. Blow out all passages and position sensor) "1" except when jets with compressed air. changing the throttle position sen- •...
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CARBURETOR AND REED VALVE CHECKING THE REED VALVE MEASURING AND ADJUSTING 1. Measure: THE FLOAT HEIGHT Install the reed valve spacer with its • Reed valve bending "a" 1. Measure: chamfered side "a" to the right. Out of specification → Replace. •...
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CARBURETOR AND REED VALVE 3. Install: 10. Install: • Pilot air screw "1" • Throttle cable "1" • Throttle stop screw "2" • Locknut "2" Locknut: Note the following installation 4 Nm (0.4 m•kg, 2.9 points: ft•lb) a. Turn in the pilot air screw until it is •...
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CARBURETOR AND REED VALVE INSTALLING THE CARBURETOR 1. Install: • Carburetor "1" Install the projection between the car- buretor joint slots. 2. Tighten: • Screw (carburetor joint) "1" 3. Tighten: • Screw (air cleaner joint) "1" Place the screw head "a" with its top as shown and secure the clamp in alignment with the horizontal line "b"...
CYLINDER HEAD, CYLINDER AND PISTON CYLINDER HEAD, CYLINDER AND PISTON REMOVING THE CYLINDER HEAD AND CYLINDER 34 Nm (3.4 m kg, 24 ft lb) 64 Nm (6.4 m kg, 46 ft lb) 20 Nm (2.0 m kg, 14 ft lb) 5 Nm (0.5 m kg, 3.6 ft lb) 25 Nm (2.5 m kg, 18 ft lb) 13 Nm (1.3 m kg, 9.4 ft lb)
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CYLINDER HEAD, CYLINDER AND PISTON REMOVING THE PISTON AND POWER VALVE 6 Nm (0.6 m kg, 4.3 ft lb) 4 Nm (0.4 m kg, 2.9 ft lb) 4 Nm (0.4 m kg, 2.9 ft lb) 4 Nm (0.4 m kg, 2.9 ft lb) 4 Nm (0.4 m kg, 2.9 ft lb) Order Part name...
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CYLINDER HEAD, CYLINDER AND PISTON REMOVING THE PUSH ROD ure-eight sanding pattern. 1. Remove: • Bolt (push rod) "1" To ensure an even surface rotate the • Push rod "2" cylinder head several times. Insert the set pin "3" included in own- er's tool kit to remove the bolt (push rod).
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CYLINDER HEAD, CYLINDER AND PISTON 3. Measure: Out of specification → Replace. • Cylinder bore "C" Dis- Use cylinder gauge "1". tance Piston dia. Out of limit → Replace. "b" 17.5 66.352–66.367 Measure the cylinder bore "C" in par- mm (2.6120– allel (A, B, C) to and at right angles to (0.69 in) 2.6129 in)
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CYLINDER HEAD, CYLINDER AND PISTON 3. Measure: • Cylinder mark "a" • Side clearance When you purchase a cylinder, you Cylinder mark Cylinder size Use a thickness gauge "1". cannot designate its size. Choose the "a" Out of limit → Replace piston and/ piston that matches the above chart.
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CYLINDER HEAD, CYLINDER AND PISTON • Before installing the piston pin clip, • Nut (cylinder) "1" cover the crankcase with a clean Nut (cylinder): rag to prevent the piston pin clip 42 Nm (4.2 m•kg, 30 from falling into the crankcase cavi- ft•lb) Tighten the nuts in stage, using a crisscross pattern.
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CYLINDER HEAD, CYLINDER AND PISTON 6. Install: • O-ring "1" • Dowel pin "2" Apply the lithium soap base grease on the O-rings. 7. Install: • Cylinder head "1" • Copper washer "2" • Nut (cylinder head) "3" Nut (cylinder head): 25 Nm (2.5 m•kg, 18 ft•lb) Tighten the nuts (cylinder head) in...
CLUTCH CLUTCH REMOVING THE CLUTCH 10 Nm (1.0 m kg, 7.2 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) Order Part name Q'ty Remarks Refer to "CHANGING THE TRANSMISSION Drain the transmission oil. OIL" section in the CHAPTER 3. Bolt (brake pedal) Shift the brake pedal downward.
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CLUTCH REMOVING THE CLUTCH BOSS 75 Nm (7.5 m kg, 54 ft lb) 6 Nm (0.6 m kg, 4.3 ft lb) Order Part name Q'ty Remarks Push rod 1 Circlip Washer Bearing Push rod 2 Nut (clutch boss) Refer to removal section. Lock washer Refer to removal section.
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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 • Clutch plate "2" • Bolt (clutch spring) "2" Bolt (clutch spring): • Install the clutch plates and friction 10 Nm (1.0 m•kg, 7.2 plates alternately on the clutch ft•lb) boss, starting with a friction plate and ending with a friction plate. Tighten the bolts in stage, using a •...
KICK SHAFT AND SHIFT SHAFT KICK SHAFT AND SHIFT SHAFT REMOVING THE PRIMARY DRIVE GEAR 30 Nm (3.0 m kg, 22 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) 55 Nm (5.5 m kg, 40 ft lb) Order Part name Q'ty Remarks...
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KICK SHAFT AND SHIFT SHAFT REMOVING THE KICK SHAFT AND SHIFT SHAFT 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) 10 Nm (1.0 m kg, 7.2 ft lb) Order Part name Q'ty...
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KICK SHAFT AND SHIFT SHAFT REMOVING THE PRIMARY DRIVE Rough spot/Seizure → Replace GEAR the stopper lever. 1. Loosen: • Torsion spring "3" • Bolt (primary drive gear) "1" Broken → Replace. Place an aluminum plate "a" between the teeth of the primary drive gear "2" and driven gear "3".
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KICK SHAFT AND SHIFT SHAFT INSTALLING THE SHIFT GUIDE INSTALLING THE SHIFT SHAFT 3. Install: AND SHIFT LEVER ASSEMBLY 1. Install: • Spring guide "1" 1. Install: • Roller "1" • Spring "1" • Washer "2" Slide the spring guide into the kick •...
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KICK SHAFT AND SHIFT SHAFT INSTALLING THE KICK IDLE GEAR Install the kick starter closest to but 1. Install: not contacting the clutch cover • Kick idle gear "1" mounting boss "a". • Washer "2" • Circlip "3" • Apply the transmission oil on the 4.
WATER PUMP WATER PUMP DISASSEMBLING THE WATER PUMP 10 Nm (1.0 m kg, 7.2 ft lb) 14 Nm (1.4 m kg, 10 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) Order Part name Q'ty Remarks Refer to "KICK SHAFT AND SHIFT SHAFT" Crankcase cover (right) section.
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WATER PUMP REMOVING THE IMPELLER • Gear teeth "a" SHAFT Wear/damage → Replace. 1. Remove: • Impeller "1" • Washer "2" • Impeller shaft "3" Hold the impeller shaft on its width INSTALLING THE IMPELLER across the flats "a" with spanners, SHAFT etc.
CDI MAGNETO CDI MAGNETO REMOVING THE CDI MAGNETO 7 Nm (0.7 m kg, 5.1 ft lb) 5 Nm (0.5 m kg, 3.6 ft lb) 56 Nm (5.6 m kg, 40 ft lb) Order Part name Q'ty Remarks Refer to "SEAT, FUEL TANK AND SIDE Seat and fuel tank COVERS"...
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CDI MAGNETO REMOVING THE ROTOR INSTALLING THE CDI MAGNETO CHAPTER 3. 1. Remove: 1. Install: Ignition timing (B.T.D.C): • Nut (rotor) "1" • Stator "1" 0.18 mm (0.007 in) • Washer "2" • Screw (stator) "2" Use the rotor holding tool "3". 5.
ENGINE REMOVAL ENGINE REMOVAL REMOVING THE ENGINE 34 Nm (3.4 m kg, 24 ft lb) 64 Nm (6.4 m kg, 46 ft lb) 26 Nm (2.6 m kg, 19 ft lb) 85 Nm (8.5 m kg, 61 ft lb) 64 Nm (6.4 m kg, 46 ft lb) 5 Nm (0.5 m kg, 3.6 ft lb) 75 Nm (7.5 m kg, 54 ft lb) 4 Nm (0.4 m kg, 2.9 ft lb)
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ENGINE REMOVAL 34 Nm (3.4 m kg, 24 ft lb) 64 Nm (6.4 m kg, 46 ft lb) 26 Nm (2.6 m kg, 19 ft lb) 85 Nm (8.5 m kg, 61 ft lb) 64 Nm (6.4 m kg, 46 ft lb) 5 Nm (0.5 m kg, 3.6 ft lb) 75 Nm (7.5 m kg, 54 ft lb) 4 Nm (0.4 m kg, 2.9 ft lb)
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ENGINE REMOVAL HANDLING NOTE • Spring "1" • Brake pedal "2" • O-ring "3" Support the machine securely so • Bolt (brake pedal) "4" there is no danger of it falling over. Bolt (brake pedal): 26 Nm (2.6 m•kg, 19 REMOVING THE DRIVE ft•lb) SPROCKET...
CRANKCASE AND CRANKSHAFT CRANKCASE AND CRANKSHAFT REMOVING THE CRANKSHAFT 14 Nm (1.4 m kg, 10 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) 30 Nm (3.0 m kg, 22 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) Order Part name Q'ty...
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CRANKCASE AND CRANKSHAFT 14 Nm (1.4 m kg, 10 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) 30 Nm (3.0 m kg, 22 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) Order Part name Q'ty Remarks Crankcase (left) Refer to removal section.
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CRANKCASE AND CRANKSHAFT REMOVING THE SEGMENT 1. Remove: • Bolt (segment) "1" • Segment "2" Turn the segment counterclockwise until it stops and loosen the bolt. REMOVING THE CRANKSHAFT CHECKING THE CRANKCASE 1. Remove: 1. Inspect: If the segment gets an impact, it •...
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"3": YU-90050/90890-01275 4. Apply: Adapter "4": • Sealant YU-90063/90890-01278 On the right crankcase "1" YAMAHA Bond No.1215 • Hold the connecting rod at top dead ® (ThreeBond No.1215): center with one hand while turning 90890-85505 the nut of the installing tool with the other.
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CRANKCASE AND CRANKSHAFT 8. Install: • Segment "1" • Bolt (segment) "2" Bolt (segment): 30 Nm (3.0 m•kg, 22 ft•lb) 6. Install: • When installing the segment onto • Holder (except for USA and CDN) the shift cam "3", align the punch "1"...
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". • Be sure the circlip end "c" is posi- tioned at axle spline groove "d".
FRONT WHEEL AND REAR WHEEL CHASSIS This section is intended for those who have basic knowledge and skill concerning the servicing of Yamaha motorcycles (e.g., Yamaha dealers, service engineers, etc.) Those who have little knowledge and skill concerning servicing are request- ed not to undertake inspection, adjustment, disassembly, or reassembly only by reference to this manual.
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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.
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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 2. Install: • Nut (wheel axle) "1" • Brake disc "1" Nut (wheel axle): Do not strike the inner race of the • Bolt (brake disc) "2" 105 Nm (10.5 m•kg, 75 bearing. Contact should be made Bolt (brake disc): ft•lb) only with the outer race.
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FRONT WHEEL AND REAR WHEEL 4. Install: • Collar "1" Temporarily tighten the nut (wheel 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...
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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 4. Inspect: HANDLING NOTE • Brake master cylinder piston "1" Apply the brake fluid on the piston • Brake master cylinder cup "2" wall. • All internal parts should be Wear/damage/score marks → Re- cleaned in new brake fluid only. place brake master cylinder kit.
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FRONT BRAKE AND REAR BRAKE 4. Install: • 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) 4. Install: • Brake master cylinder kit "1" •...
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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- •...
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FRONT BRAKE AND REAR BRAKE 3. Pass the brake hose through the cable guide "1". • Use only the designated quality brake fluid: otherwise, the rubber seals may deteriorate, causing leakage and poor brake performance. • Refill with the same type of brake fluid;...
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FRONT BRAKE AND REAR BRAKE 4. Install: • Reservoir float (front brake) • Diaphragm • Brake master cylinder cap "1" • Screw (brake master cylinder cap) "2" Screw (bolt) {brake mas- ter cylinder cap}: 2 Nm (0.2 m•kg, 1.4 ft•lb) After installation, while pulling the brake lever in or pushing down on the brake pedal, check whether...
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"...
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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 Use the dial gauge "1". CHECKING THE BASE VALVE 1. Inspect: Inner tube bending limit: • Be sure to use recommended • Base valve "1" 0.2 mm (0.008 in) fork oil. If other oils are used, Wear/damage → Replace. they may have an excessively ad- Contamination →...
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FRONT FORK 6. Tighten: base valve with specified torque. • Locknut "1" Cap bolt wrench: Fully finger tighten the locknut onto YM-01500/90890-01500 the damper assembly. Cap bolt ring wrench: YM-01501/90890-01501 15. Install: • Dust seal "1" • Stopper ring "2" •...
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FRONT FORK 17. Install: • Outer tube "1" To inner tube "2". 21. Install: 25. Install: • Dust seal "1" • Damper assembly "1" To inner tube "2". 18. Install: Apply the lithium soap base grease • Slide metal "1" on the inner tube.
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FRONT FORK 27. Install: 32. Install: • Push rod "1" • Damper assembly "1" • Copper washer "2" To outer tube. • Adjuster "3" To damper assembly "4". Temporarily tighten the damper as- sembly. • While compressing the inner tube "5", set the cap bolt ring wrench "7"...
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FRONT FORK 2. Tighten: 5. Install: • Damper assembly "1" • Protector "1" • Bolt (protector) "2" Damper assembly: 30 Nm (3.0 m•kg, 22 Bolt (protector): ft•lb) 5 Nm (0.5 m•kg, 3.6 ft•lb) Use the cap bolt ring wrench "2" to tighten the damper assembly with specified torque.
HANDLEBAR HANDLEBAR REMOVING THE HANDLEBAR 1 Nm (0.1 m kg, 0.7 ft lb) 9 Nm (0.9 m kg, 6.5 ft lb) 28 Nm (2.8 m kg, 20 ft lb) 4 Nm (0.4 m kg, 2.9 ft lb) 4 Nm (0.4 m kg, 2.9 ft lb) 40 Nm (4.0 m kg, 29 ft lb) 4 Nm (0.4 m kg, 2.9 ft lb) Order...
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HANDLEBAR DISASSEMBLING THE THROTTLE Order Part name Q'ty Remarks Grip cap (lower) Grip cap (upper) Grip assembly Grip (right) Refer to removal section. Tube guide 5-25...
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HANDLEBAR REMOVING THE BRAKE MASTER surface "a" with a lacquer thinner. CYLINDER • Align the mating mark "b" on the 1. Remove: grip (right) with the slot "c" in the • Brake master cylinder bracket "1" tube guide. • Brake master cylinder "2" •...
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HANDLEBAR • Throttle cables "1" To tube guide "2". Apply the lithium soap base grease on the throttle cable end and tube guide cable winding portion. 3. Tighten: 11. Install: • Nut (handlebar lower holder) "1" • Brake master cylinder "1" •...
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HANDLEBAR 13. Install: • Engine stop switch "1" • Clutch lever holder "2" • Bolt (clutch lever holder) "3" Bolt (clutch lever holder): 4 Nm (0.4 m•kg, 2.9 ft•lb) • Clamp "4" • The engine stop switch, clutch lever holder and clamp should be in- stalled according to the dimensions shown.
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. 5-30...
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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. 5-34...
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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- •...
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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 56 Nm (5.6 m kg, 40 ft lb) 32 Nm (3.2 m kg, 23 ft lb) 29 Nm (2.9 m kg, 21 ft lb) 53 Nm (5.3 m kg, 38 ft lb) Order Part name Q'ty...
REAR SHOCK ABSORBER 56 Nm (5.6 m kg, 40 ft lb) 32 Nm (3.2 m kg, 23 ft lb) 29 Nm (2.9 m kg, 21 ft lb) 53 Nm (5.3 m kg, 38 ft lb) Order Part name Q'ty Remarks Bearing Refer to removal section.
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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 Bends/damage → Replace rear back the bearing until it contacts the shock absorber assembly.
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REAR SHOCK ABSORBER 3. Install: 4. Adjust: 3. Install: • Lower bearing "1" • Spring length (installed) • Rear shock absorber Refer to "ADJUSTING THE 4. Install: REAR SHOCK ABSORBER • Bolt (rear shock absorber-frame) Install the bearing by pressing it on SPRING PRELOAD"...
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ELECTRICAL This section is intended for those who have basic knowledge and skill concerning the servicing of Yamaha motorcycles (e.g., Yamaha dealers, service engineers, etc.) Those who have little knowledge and skill concerning servicing are request- ed not to undertake inspection, adjustment, disassembly, or reassembly only by reference to this manual. It may lead to...
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. No spark ↓...
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IGNITION SYSTEM SPARK GAP TEST Not conductive while it is pushed → 1. Disconnect the spark plug cap Replace. from spark plug. Conductive while it is freed → Re- 2. Connect the dynamic spark tester place. "1" (ignition checker "2") as shown.
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IGNITION SYSTEM CHECKING THE CDI MAGNETO 1. Inspect: • Pickup coil resistance Out of specification → Replace. Tester (+) lead → White/Red lead "1" Tester (-) lead → White/Blue lead "2" CHECKING THE NEUTRAL SWITCH Tester se- Pickup coil 1. Inspect: lector posi- resistance •...
SOLENOID VALVE SYSTEM SOLENOID VALVE SYSTEM INSPECTION STEPS If the solenoid valve will not operate, use the following inspection steps. Check each couplers and wire connection. No good → Repair or replace. OK ↓ Check solenoid valve. (Check solenoid valve op- No good →...
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SOLENOID VALVE SYSTEM CHECKING THE COUPLERS AND LEADS CONNECTION 1. Check: • Couplers and leads connection Rust/ Dust/ Looseness/Short-cir- cuit → Repair or replace. CHECKING THE SOLENOID VALVE OPERATION 1. Disconnect the solenoid valve coupler. 2. Connect 12V battery to the sole- noid valve coupler.
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. OK ↓ Check throttle position sensor. (Throttle position No good →...
THROTTLE POSITION SENSOR SYSTEM HANDLING NOTE Out of specification → Replace. Tester (+) lead → Yellow lead "2" Tester (-) lead → Black lead "3" Do not loosen the screw (throttle position sensor) "1" except when Tester Throttle position changing the throttle position sen- selec- sensor coil vari- sor due to failure because it will...
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THROTTLE POSITION SENSOR SYSTEM throttle position sensor and car- buretor. 7. Insert the thin electric conductors 11. Stop the engine. "2" (lead wire) into the throttle po- 12. Remove: sition sensor coupler "1", as • Carburetor shown, and connect the tester to Refer to "CARBURETOR AND them.
ENGINE TUNING amount of oxygen in the air by so EFFECT OF SETTING PARTS IN much of the water vapor in the RELATION TO THROTTLE VALVE ENGINE same air. OPENING CARBURETOR SETTING • Lower atmospheric pressure (at a • The role of fuel is to cool the engine, high altitude) reduces the density of and in the case of a 2-stroke en- the air.
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The richness of air-fuel mixture with On the carburetors used in the the throttle fully closed to 1/2 open YZ250, the main nozzle is press-fit- can be set by changing the pilot jet ted, so it can not be replaced. There- "1".
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ENGINE RELATIONSHIP WITH THROTTLE CARBURETOR SETTING PARTS Part OPENING Jet nee- Size number Main jet Part number The flow of the fuel through the car- dle "3" Size (-14916-) "1" (-14943-) buretor main system is controlled by Rich N8RH 4SR-RH the main jet and then, it is further reg- Rich #190 4MX-45...
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ENGINE ROAD CONDITION AND EXAMPLES OF CARBURETOR SETTING General condition Sandy condition Under 10°C 15–25°C (59– Over 25°C Under 10°C 15–25°C (59– Over 25°C (50°F) 77°F) (77°F) (50°F) 77°F) (77°F) (Winter) (Spring, Au- (Summer) (Winter) (Spring, Au- (Summer) tumn) tumn) Main jet #178 #178...
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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 Clogged fuel hose...
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CHASSIS CHANGE OF THE HEAT RANGE a longer straight portion of a speed OF SPARK PLUGS course and should be increased for Judging from the discoloration of a course with many corners. Actual- spark plugs, if they are found improp- ly, however, as the speed depends er, it can be corrected by the following on the ground condition of the day...
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CHASSIS riding feeling. Rebound damping REAR SUSPENSION SETTING tends to become stronger and the The rear suspension setting should Adjust the oil amount in 5 cm (0.2 front fork may sink deeply over a se- be made depending on the rider's Imp oz, 0.2 US oz) increments or ries of gaps.
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CHASSIS set length, replace the spring with REAR SHOCK ABSORBER an optional one and make readjust- SETTING PARTS • The unequal-pitch spring is softer in ment. • Rear shock spring "1" initial characteristic than the equal- [Equal-pitch titanium spring] pitch spring and is difficult to bottom out under full compression.
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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...