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2013 q Read this manual carefully before operating this vehicle. q Il convient de lire attentivement ce manuel avant la première utilisation du véhicule. q 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...
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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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2013 2013 Read this manual carefully before operating this vehicle. Read this manual carefully before operating this vehicle. OWNER’S SERVICE MANUAL OWNER’S SERVICE MANUAL YZ125(D) YZ125(D) 1SR-28199-31-E0 1SR-28199-31-E0...
ORDER. Congratulations on your purchase of distinguished in this manual by the For safety and reliability, the ma- a Yamaha YZ series. This model is following notations. chine must be properly maintained. the culmination of Yamaha's vast ex- Always perform the pre-operation perience in the production of paceset- checks indicated in this manual.
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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 INSPEC- CHASSIS INFORMATION TION AND AD- JUSTMENTS FRONT WHEEL AND REAR WHEEL ......5-1 LOCATION OF IMPORTANT FRONT BRAKE AND LABELS......1-1 MAINTENANCE REAR BRAKE ....5-6 DESCRIPTION ....1-5 INTERVALS...... 3-1 FRONT FORK....5-16 CONSUMER PRE-OPERATION HANDLEBAR....5-24...
LOCATION OF IMPORTANT LABELS GENERAL INFORMATION LOCATION OF IMPORTANT LABELS Please read the following important labels carefully before operating this vehicle. CANADA...
LOCATION OF IMPORTANT LABELS EUROPE AUS, NZ, ZA...
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LOCATION OF IMPORTANT LABELS Familiarize yourself with the following pictograms and read the explanatory text. Read Owner's service manual. This unit contains high-pressure nitrogen gas. Mishandling can cause explosion. Do not incinerate, puncture or open. Turn off the main switch after riding to avoid draining the battery. Use unleaded gasoline only.
DESCRIPTION DESCRIPTION Clutch lever 14. Fuel cock Engine stop switch 15. Air filter Front brake lever 16. Drive chain Throttle grip 17. Shift pedal Radiator cap 18. Starter knob Fuel tank cap 19. Front fork Kickstarter crank Fuel tank Radiator 10.
1. Remove all dirt, mud, dust, and 1. When ordering parts, you can transporting it. foreign material before removal give the number to your Yamaha and disassembly. dealer for positive identification of • When washing the machine with • Never apply additional force to the model you own.
5. Keep away from fire. nal into the connector. age to the bearing surfaces. ALL REPLACEMENT PARTS 1. We recommend to use Yamaha genuine parts for all replace- ments. Use oil and/or grease rec- ommended by Yamaha for assembly and adjustment.
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 Fuel level gauge "1" This gauge is used to measure the YM-1312-A, 90890-01312 fuel level in the float chamber. Fuel level gauge adaptor "2" YM-01470, 90890-01470 Radiator cap tester These tools are used for checking YU-24460-01, 90890-01325 the cooling system.
Dynamic spark tester This instrument is necessary for YM-34487 checking the ignition system compo- Ignition checker nents. 90890-06754 Yamaha Bond No. 1215 (Three- This sealant (Bond) is used for ® Bond No. 1215) crankcase mating surface, etc. 90890-85505 1-10...
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.
STARTING AND BREAK-IN STARTING AND BREAK-IN AIR FILTER MAINTENANCE 5. Allow the engine to cool. Restart According to "CLEANING THE AIR the engine and operate the ma- FUEL FILTER ELEMENT" section in the chine as in the step above for five Mix oil with the gas at the ratio speci- CHAPTER 3, apply the foam-air-filter minutes.
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: YZ125D (USA, CDN, AUS, NZ) YZ125 (EUROPE, ZA) Model code number: 1SR5 (USA, CDN) 1SR6 (EUROPE) 1SR8 (AUS, NZ, ZA) Dimensions: USA, AUS, NZ, ZA EUROPE, CDN Overall length 2,135 mm (84.1 in) 2,139 mm (84.2 in) Overall width 827 mm (32.6 in)
MAINTENANCE SPECIFICATIONS Transmission: Primary reduction system Gear Primary reduction ratio 3.368 (64/19) Final drive Chain Secondary reduction ratio 3.692 (48/13) Transmission type Constant mesh, 6-speed Operation Left foot operation Gear ratio: 2.385 (31/13) 1.933 (29/15) 1.588 (27/17) 1.353 (23/17) 1.200 (24/20) 1.095 (23/21) Chassis: USA, AUS, ZA, NZ...
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MAINTENANCE SPECIFICATIONS Item Standard Limit Cylinder: Bore size 54.000–54.014 mm (2.1260–2.1265 in) 54.1 mm (2.130 in) Taper limit ---- 0.05 mm (0.0020 in) Out of round limit ---- 0.01 mm (0.0004 in) Piston: Piston size/ 53.957–53.972 mm (2.1243–2.1249 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 40.1 mm (1.579 in) 38.1 mm (1.500 in) Quantity...
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MAINTENANCE SPECIFICATIONS Item Standard Limit Cooling: Radiator core size: Width 107.8 mm (4.24 in) ---- Height (left) 240 mm (9.45 in) ---- Height (right) 220 mm (8.66 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)
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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 ×...
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TIGHTENING TORQUES GENERAL TORQUE TORQUE SPECIFI- SPECIFICATIONS CATION (Bolt This chart specifies torque for stan- (Nut) dard fasteners with standard I.S.O. m•kg ft•lb pitch threads. Torque specifications 6 mm for special components or assem- blies are included in the applicable sections of this book.
CABLE ROUTING DIAGRAM Install the ignition coil, side core and ground lead together to the frame. Take care to fasten the ground lead so that its terminal is within the indicated range. Clamp the throttle cable and high tension cord to the frame. Clamp the clutch cable to the left engine bracket.
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CABLE ROUTING DIAGRAM High tension cord 12. CDI unit stay Clamp to the frame the throttle Engine stop switch lead Pass the high tension cord to the cable, clutch cable, ignition coil Ignition coil lead left of the radiator hose. lead and engine stop switch Clamp Using a plastic locking tie, clamp...
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CABLE ROUTING DIAGRAM Pass the CDI magneto lead and radiator breather hose between the frame and the radiator (right). Clamp the CDI magneto lead to the frame at its locating tape. Bring the connector cover into contact with the coupler. Locate the clamp ends in the ar- rowed range.
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CABLE ROUTING DIAGRAM Master cylinder If the brake hose contacts the Brake hose holder spring (rear shock absorber), Brake hose correct its twist. Install the brake hose so that its Install the brake hose so that its pipe portion directs as shown pipe portion directs as shown and lightly touches the projec- and lightly touches the projec-...
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CABLE ROUTING DIAGRAM 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 switch lead and lightly touches the projec- the cable guide.
If you are a doubt as to what intervals to follow in maintaining and lubricating your machine, consult your Yamaha dealer. • Periodic inspection is essential in making full use of the machine performance. The service life of the parts varies sub- stantially according to the environment in which the machine runs (e.g., rain, dirt, etc.).
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MAINTENANCE INTERVALS Every Every Every race third fifth As re- After Item (about (about (about Remarks break-in quired 12.5 hours) hours) hours) ROTOR NUT Retighten ● ● MUFFLER Inspect ● ● Clean ● Retighten ● ● Replace fiber * When the exhaust sound be- ●...
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MAINTENANCE INTERVALS Every Every Every race third fifth After As re- (about (about (about Item Remarks break-in quired 12.5 hours) hours) hours) BRAKES Adjust lever position and ● ● pedal height Lubricate pivot point ● ● Check brake disc surface ●...
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Retighten sprocket bolt ● ● Inspect bearings ● Replace bearings ● Lubricate Lithium base grease ● THROTTLE, CONTROL CA- Check routing and connec- ● ● tion Lubricate Yamaha cable lube or SAE ● ● 10W-40 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 2. Remove: • Coolant drain bolt "1" Handling notes of coolant: CHECKING THE COOLANT LEVEL The coolant is harmful so it should be handled with special care. Do not remove the radiator cap "1", drain bolt and hoses when the engine and radiator are hot.
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ENGINE Radiator cap ADJUSTING THE CLUTCH LEVER ADJUSTING THE THROTTLE GRIP 2. Apply the specified pressure. FREE PLAY FREE PLAY 1. Check: 1. Check: Radiator cap opening • Clutch lever free play "a" • Throttle grip free play "a" pressure: Out of specification →...
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ENGINE LUBRICATING THE THROTTLE 2. Clean: 7. Install: 1. Remove: • Air filter element • Air filter element "1" • Cap cover "1" Clean them with solvent. • Washer • Throttle cable cap "2" • Fitting bolt After cleaning, remove the remaining Fitting bolt: solvent by squeezing the element.
CHASSIS c. Inspect the gasket (oil check bolt), 6. Fill: replace if damaged. • Transmission oil d. Tighten the oil check bolt. Recommended brand: Oil check bolt: YAMALUBE 10 Nm (1.0 m•kg, 7.2 Recommended engine ft•lb) oil type SAE10W-40 Recommended engine oil grade API service SG type or CHECKING THE EXHAUST PIPE...
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CHASSIS ADJUSTING THE FRONT BRAKE 1. Check: • Brake lever position "a" Brake lever position "a": Standard posi- Extent of ad- tion justment 2. Adjust: 86–105 mm 95 mm (3.74 in) • Brake pedal height (3.39–4.13 in) Pedal height adjustment steps: a.
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CHASSIS g. Tighten the bleed screw. CHECKING AND REPLACING THE REAR BRAKE PADS Bleed screw: 1. Inspect: 6 Nm (0.6 m•kg, 4.3 • Brake pad thickness "a" ft•lb) Out of specification → Replace as h. Install the brake pads "7" and pad a set.
CHASSIS e. Connect the transparent hose "8" k. Install the pad pin plug "15" and to the bleed screw "9" and place protector "16". • Use only designated quality the suitable container under its Pad pin plug: brake fluid to avoid poor brake end.
CHASSIS 6. Lubricate: c. Turn each adjuster exactly the • Drive chain same amount to maintain correct axle alignment. (There are marks Drive chain lubricant: "a" on each side of the drive chain SAE 10W-40 motor oil puller alignment.) NOTICE: Im- or suitable chain lubri- proper drive chain slack will cants...
CHASSIS CLEANING THE FRONT FORK OIL ADJUSTING THE FRONT FORK Extent of adjustment: SEAL AND DUST SEAL REBOUND DAMPING FORCE 1. Remove: 1. Adjust: Maximum Minimum • Protector • Rebound damping force • Dust seal "1" By turning the adjuster "1". 20 clicks out Fully turned in Stiffer "a"...
CHASSIS 3. Measure: Extent of adjustment: • Spring fitting length Maximum Minimum Standard fitting length: 20 clicks out Fully turned in I.D. MARK/ (from maximum Length position Q'TY position) Red/1 258 mm (10.16 in) Extent of adjustment: *252 mm (9.92 in) Maximum Minimum Red/2...
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CHASSIS • STANDARD POSITION: This is the position which is back by the specific number of turns from the fully turned-in position. (Which align the punch mark "a" on the adjuster with the punch mark "b" on the adjuster body.) Standard position: •...
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CHASSIS CHECKING AND ADJUSTING THE STEERING HEAD • Apply the lithium soap base grease First tighten the bolts on the front 1. Place a stand under the engine to on the thread of the steering stem. side of the handlebar upper holder, raise the front wheel off the •...
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Wipe off any excess grease, and Clutch lever pivot 11. Clutch cable end avoid getting grease on the brake Shift pedal pivot Use Yamaha cable lube or discs. Footrest pivot equivalent on these areas. Throttle-to-handlebar contact Use SAE 10W-40 motor oil or Drive chain suitable chain lubricants.
ELECTRICAL CHECKING THE IGNITION TIMING 7. Adjust: ELECTRICAL 1. Remove: • Ignition timing 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) 12 Nm (1.2 m kg, 8.7 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) 12 Nm (1.2 m kg, 8.7 ft lb) 12 Nm (1.2 m kg, 8.7 ft lb) Order Part name...
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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) 2 Nm (0.2 m kg, 1.4 ft lb) Order Part name Q'ty...
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RADIATOR HANDLING NOTE 2. Install: • Right radiator "1" Fit the hook "a" on the inner side first • Washer "2" into the radiator. Do not remove the radiator cap • Bolt (right radiator) "3" when the engine and radiator are Bolt (right radiator): hot.
CARBURETOR AND REED VALVE CARBURETOR AND REED VALVE REMOVING THE CARBURETOR AND REED VALVE 2 Nm (0.2 m kg, 1.4 ft lb) 2 Nm (0.2 m kg, 1.4 ft lb) 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...
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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 Refer to removal section. Throttle valve Needle holder Jet needle Float chamber Needle jet cover Float pin Float Valve seat Main jet...
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CARBURETOR AND REED VALVE HANDLING NOTE CHECKING THE JET NEEDLE 1. Inspect: • Jet needle "1" Do not disassemble the venturi Bends/wear → Replace. block "1" and main nozzle "2" be- • Clip groove cause it will cause a drop in carbu- Free play exists/wear →...
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CARBURETOR AND REED VALVE d. Measure the fuel level with the 2. Measure: fuel level gauge. • Valve stopper height "a" Out of specification → Adjust stopper/Replace valve stopper. Keep the carburetor and fuel level gauge vertically when measuring the Valve stopper height "a": fuel level.
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CARBURETOR AND REED VALVE • After installing the needle valve to the float, install them to the carbure- tor. • Check the float for smooth move- ment. 2. Tighten: • Bolt (air filter joint) "1" Bolt (air filter joint): 2 Nm (0.2 m•kg, 1.4 ft•lb) •...
CYLINDER HEAD, CYLINDER AND PISTON CYLINDER HEAD, CYLINDER AND PISTON REMOVING THE CYLINDER HEAD AND CYLINDER 20 Nm (2.0 m kg, 14 ft lb) 28 Nm (2.8 m kg, 20 ft lb) 34 Nm (3.4 m kg, 24 ft lb) 13 Nm (1.3 m kg, 9.4 ft lb) 30 Nm (3.0 m kg, 22 ft lb) 4 Nm (0.4 m kg, 2.9 ft lb)
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CYLINDER HEAD, CYLINDER AND PISTON REMOVING THE PISTON AND POWER VALVE 4 Nm (0.4 m kg, 2.9 ft lb) 8 Nm (0.8 m kg, 5.8 ft lb) 4 Nm (0.4 m kg, 2.9 ft lb) 5 Nm (0.5 m kg, 3.6 ft lb) Order Part name Q'ty...
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CYLINDER HEAD, CYLINDER AND PISTON REMOVING THE PUSH ROD 3. Remove: 1. Remove: • Piston ring "1" • Bolt (push rod) "1" • Push rod "2" Take care not to scratch the piston or damage the piston ring by expanding Set the collar "3"...
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CYLINDER HEAD, CYLINDER AND PISTON 4. Install: • Small end bearing Standard Wear limit • Piston pin Into the small end of connecting 54.000– Cylin- rod. 54.014 mm 54.1 mm der bore 5. Check: (2.1260– (2.130 in) "C" • Free play 2.1265 in) There should be no noticeable Taper...
CYLINDER HEAD, CYLINDER AND PISTON • Collar "5" Wear/Damage → Replace. • Spring "6" Broken → Replace. 2. Check: • Piston mark "a" Piston mark "a" Piston size (color) CHECKING THE POWER VALVE 53.957–53.960 HOLE ON CYLINDER 1. Remove: A (red) (2.1243–2.1244 •...
CYLINDER HEAD, CYLINDER AND PISTON • Before installing the piston pin clip, cover the crankcase with a clean • Install the spring to the link lever, rag to prevent the piston pin clip and then to the cylinder. from falling into the crankcase cavi- •...
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CYLINDER HEAD, CYLINDER AND PISTON 3. Install: 9. Install: • Nut (cylinder) "1" • Spark plug "1" Nut (cylinder): Spark plug: 30 Nm (3.0 m•kg, 22 20 Nm (2.0 m•kg, 14 ft•lb) ft•lb) • Spark plug cap "2" Tighten the nuts in stage, using a 6.
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 80 Nm (8.0 m kg, 58 ft lb) Order Part name Q'ty Remarks Push rod 1 Circlip Washer Bearing Ball Push rod 2 Nut (clutch boss) Refer to removal section. Lock washer Refer to removal section. Clutch boss Refer to removal section.
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CLUTCH REMOVING THE CLUTCH BOSS CHECKING THE CLUTCH CHECKING THE PUSH LEVER 1. Remove: SPRINGS SHAFT • Nut "1" 1. Measure: 1. Inspect: • Lock washer "2" • Clutch spring free length "a" • Push lever shaft "1" • Clutch boss "3" Out of specification →...
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CLUTCH 5. Install: 9. Install: • Friction plate "1" • Clutch spring "1" • 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.
KICK SHAFT AND SHIFT SHAFT KICK SHAFT AND SHIFT SHAFT REMOVING THE PRIMARY DRIVE GEAR Order Part name Q'ty Remarks Refer to "CHANGING THE TRANSMISSION Drain the transmission oil. OIL" section in the CHAPTER 3. Clutch cable Disconnect at engine side. Bolt (brake pedal) Shift the brake pedal downward.
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KICK SHAFT AND SHIFT SHAFT REMOVING THE KICK SHAFT AND SHIFT SHAFT Order Part name Q'ty Remarks Kick idle gear Kick shaft assembly Refer to removal section. Shift pedal Shift shaft Roller Shift guide Refer to removal section. Shift lever assembly Refer to removal section.
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KICK SHAFT AND SHIFT SHAFT REMOVING THE PRIMARY DRIVE CHECKING THE SHIFT SHAFT GEAR 1. Inspect: If the segment gets an impact, it 1. Loosen: • Shift shaft "1" may be damaged. Take care not to • Bolt (primary drive gear) "1" Bend/damage →...
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KICK SHAFT AND SHIFT SHAFT INSTALLING THE SEGMENT INSTALLING THE SHIFT GUIDE INSTALLING THE SHIFT SHAFT 1. Install: AND SHIFT LEVER ASSEMBLY 1. Install: • Segment "1" 1. Install: • Roller "1" • Bolt (segment) • Spring "1" • Shift shaft "2" •...
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KICK SHAFT AND SHIFT SHAFT 3. Install: • Kick shaft assembly "1" Tighten the bolts in stage, using a crisscross pattern. • Apply the transmission oil on the kick shaft. • Slide the kick shaft assembly into the crankcase, make sure the clip "2"...
WATER PUMP WATER PUMP DISASSEMBLING THE WATER PUMP Order Part name Q'ty Remarks Refer to "KICK SHAFT AND SHIFT SHAFT" Crankcase cover (right) section. Water pump housing cover Impeller shaft gear Dowel pin Plain washer Impeller shaft assembly Bearing Refer to removal section. Oil seal Refer to removal section.
WATER PUMP REMOVING THE OIL SEAL CHECKING THE BEARING INSTALLING THE IMPELLER 1. Inspect: SHAFT • Bearing "1" 1. Install: • Replace the oil seal when transmis- Rotate inner race with a finger. • Impeller shaft "1" sion oil or coolant leaks out from the Rough spot/seizure →...
CDI MAGNETO CDI MAGNETO REMOVING THE CDI MAGNETO Order Part name Q'ty Remarks Refer to "SEAT, FUEL TANK AND SIDE Seat and fuel tank COVERS" section. Bolt (Radiator) Refer to "RADIATOR" section. Disconnect the CDI magneto lead. Left crankcase cover Nut (rotor) Refer to removal section.
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CDI MAGNETO REMOVING THE ROTOR INSTALLING THE CDI MAGNETO 4. Adjust: 1. Remove: 1. Install: • Ignition timing • Nut (rotor) "1" • Stator "1" Refer to "CHECKING THE IGNI- • Washer "2" • Screw (stator) "2" TION TIMING" section in the Use the rotor holding tool "3".
ENGINE REMOVAL ENGINE REMOVAL REMOVING THE ENGINE 26 Nm (2.6 m kg, 19 ft lb) 34 Nm (3.4 m kg, 24 ft lb) 5 Nm (0.5 m kg, 3.6 ft lb) 64 Nm (6.4 m kg, 46 ft lb) 64 Nm (6.4 m kg, 46 ft lb) 85 Nm (8.5 m kg, 61 ft lb) 75 Nm (7.5 m kg, 54 ft lb) Order...
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ENGINE REMOVAL 26 Nm (2.6 m kg, 19 ft lb) 34 Nm (3.4 m kg, 24 ft lb) 5 Nm (0.5 m kg, 3.6 ft lb) 64 Nm (6.4 m kg, 46 ft lb) 64 Nm (6.4 m kg, 46 ft lb) 85 Nm (8.5 m kg, 61 ft lb) 75 Nm (7.5 m kg, 54 ft lb) Order...
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ENGINE REMOVAL HANDLING NOTE Support the machine securely so there is no danger of it falling over. REMOVING THE DRIVE SPROCKET 1. Remove: INSTALLING THE ENGINE • Nut (drive sprocket) "1" 1. Install: • Lock washer "2" • Engine "1" Install the engine from right side.
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ENGINE REMOVAL 2. Install: • Lock washer "1" • Nut (drive sprocket) "2" Nut (drive sprocket): 75 Nm (7.5 m•kg, 54 ft•lb) Tighten the nut while applying the rear brake. 3. Bend the lock washer tab to lock the nut. 4.
CRANKCASE AND CRANKSHAFT CRANKCASE AND CRANKSHAFT REMOVING THE CRANKSHAFT 30 Nm (3.0 m kg, 22 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) 14 Nm (1.4 m kg, 10 ft lb) 20 Nm (2.0 m kg, 14 ft lb) Order Part name Q'ty...
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CRANKCASE AND CRANKSHAFT 30 Nm (3.0 m kg, 22 ft lb) 10 Nm (1.0 m kg, 7.2 ft lb) 14 Nm (1.4 m kg, 10 ft lb) 20 Nm (2.0 m kg, 14 ft lb) Order Part name Q'ty Remarks Crankshaft 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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Crack • Sealant mm (2.201– — Crankshaft installing pot width: On the right crankcase "1". 2.203 in) "2": YU-90050/90890-01274 Yamaha Bond No.1215 ® Crankshaft installing bolt (ThreeBond No.1215): "3": 90890-85505 YU-90050/90890-01275 Adapter "4": Clean the contacting surface of left YU-90063/90890-01278 and right crankcase before applying the sealant.
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"a" where the crank- Unsmooth operation → Repair. shaft and bearing come in contact. Bolt (holder): • Use two plain washers (Yamaha 10 Nm (1.0 m•kg, 7.2 genuine: 90201-243K3) "5" or the If the crankshaft will not turn smooth- ft•lb)
TRANSMISSION, SHIFT CAM AND SHIFT FORK TRANSMISSION, SHIFT CAM AND SHIFT FORK REMOVING THE TRANSMISSION, SHIFT CAM AND SHIFT FORK 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 Engine Refer to "ENGINE REMOVAL"...
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TRANSMISSION, SHIFT CAM AND SHIFT FORK REMOVING THE TRANSMISSION CHECKING THE SHIFT FORK, 1. Remove: SHIFT CAM AND SEGMENT • Main axle "1" 1. Inspect: • Drive axle "2" • Shift fork "1" Wear/damage/scratches → Re- place. • Tap lightly on the transmission drive axle with a soft hammer to remove.
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TRANSMISSION, SHIFT CAM AND SHIFT FORK 4. Check: • Shifter operation • Transmission operation Unsmooth operation → Repair. 4. Install: 2. Install: • Collar "1" • Shift cam "1" • Apply the lithium soap base grease • Apply the transmission oil on the on the oil seal lip.
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.
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: 6. Install: • Brake disc "1" • Nut (wheel axle) "1" Do not strike the inner race of the • Bolt (brake disc) "2" Nut (wheel axle): bearing. Contact should be made Bolt (brake disc): 105 Nm (10.5 m•kg, 75 only with the outer race.
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FRONT WHEEL AND REAR WHEEL 4. Install: 8. Install: • Collar "1" • Right drive chain puller "1" • Washer "2" • Nut (wheel axle) "3" Apply the lithium soap base grease on the oil seal lip. Temporarily tighten the nut (wheel axle) at this point.
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 • Replace the brake caliper piston seals and brake caliper piston dust seals whenever a caliper is disassembled. INSTALLING THE BRAKE CALIPER PISTON 1. Clean: • Brake caliper CHECKING THE BRAKE CALIPER • Brake caliper piston seal 1.
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FRONT BRAKE AND REAR BRAKE 4. Install: • Brake master cylinder kit "1" • Washer (front brake) "2" • Push rod (rear brake) "2" • Circlip "3" • Brake master cylinder boot "4" • Push rod (front brake) "5" To brake master cylinder. INSTALLING THE REAR BRAKE INSTALLING THE BRAKE CALIPER...
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FRONT BRAKE AND REAR BRAKE 4. Install: • Copper washer "1" • Use only the designated quality • Brake hose "2" brake fluid: • Union bolt "3" otherwise, the rubber seals may Union bolt: deteriorate, causing leakage and 30 Nm (3.0 m•kg, 22 poor brake performance.
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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 CHECKING THE BASE VALVE Inner tube bending limit: 1. Inspect: • Be sure to use recommended 0.2 mm (0.008 in) • Base valve "1" 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: 14. Check: • Locknut "1" • Damper assembly smooth move- Hold the damper assembly with the ment cap bolt ring wrench "2" and use the Tightness/binding/rough spots → Fully finger tighten the locknut onto cap bolt wrench "3" to tighten the Repeat the steps 2 to 13.
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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 31. Fill: 33. Install: • Front fork oil "1" • Protector guide "1" From outer tube top. Recommended oil: Suspension oil "S1" Standard oil amount: 333 cm (11.72 Imp oz, 11.26 US oz) 28. Inspect: *335 cm (11.79 Imp oz, •...
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FRONT FORK 4. Tighten: 7. Adjust: • Pinch bolt (upper bracket) "1" • Compression damping force Pinch bolt (upper brack- Turn in the damping adjuster "1" fin- et): ger-tight and then turn out to the orig- 21 Nm (2.1 m•kg, 15 inally set position.
HANDLEBAR HANDLEBAR REMOVING THE HANDLEBAR 0.5 Nm (0.05 m kg, 0.36 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) 0.5 Nm (0.05 m kg, 0.36 ft lb) 40 Nm (4.0 m kg, 29 ft lb) 4 Nm (0.4 m kg, 2.9 ft lb)
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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 CYLINDER • Before applying the adhesive, wipe 1. Remove: off grease or oil on the tube guide • Brake master cylinder bracket "1" surface "a" with a lacquer thinner. • Brake master cylinder "2" • Align the mating mark "b" on the grip (right) with the slot "c"...
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HANDLEBAR 9. Adjust: • Throttle grip free play Refer to "ADJUSTING THE THROTTLE GRIP FREE PLAY" section in the CHAPTER 3. 10. Install: • Cap cover "1" 6. Install: • Throttle cables "1" To tube guide "2". Apply the lithium soap base grease on the throttle cable end and tube guide cable winding portion.
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HANDLEBAR 15. Adjust: • Clutch lever free play After tightening the bolts, check Refer to "ADJUSTING THE that the throttle grip "2" moves CLUTCH LEVER FREE PLAY" smoothly. If it does not, retighten section in the CHAPTER 3. the bolts for adjustment. 13.
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 CHECKING THE STEERING STEM 1. Inspect: • Steering stem "1" Support the machine securely so Bend/damage → Replace. there is no danger of it falling over. REMOVING THE STEERING RING 1. Remove: 3. Install: • Steering ring nut "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 70 Nm (7.0 m kg, 50 ft lb) 2 Nm (0.2 m kg, 1.4 ft lb) 6 Nm (0.6 m kg, 4.3 ft lb) 80 Nm (8.0 m kg, 58 ft lb) Order Part name Q'ty Remarks Refer to removal section.
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SWINGARM HANDLING NOTE 2. Inspect: • Oil seal "3" Damage → Replace. Support the machine securely so there is no danger of it falling over. REMOVING THE CAP 1. Remove: • Left cap "1" 2. Install: • Bearing "1" Remove with a slotted-head screw- •...
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SWINGARM 4. Install: 7. Check: • Connecting rod "1" • Swingarm side play "a" • Bolt (connecting rod) "2" Free play exists → Replace thrust • Washer "3" bearing. • Nut (connecting rod) "4" • Swingarm up and down move- ment "b"...
REAR SHOCK ABSORBER REAR SHOCK ABSORBER REMOVING THE REAR SHOCK ABSORBER 56 Nm (5.6 m kg, 40 ft lb) 2 Nm (0.2 m kg, 1.4 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...
REAR SHOCK ABSORBER 56 Nm (5.6 m kg, 40 ft lb) 2 Nm (0.2 m kg, 1.4 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...
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To dispose of a damaged or worn- face on which the bearing is press out rear shock absorber, take the fitted. unit to your Yamaha dealer for this disposal procedure. 5-40...
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REAR SHOCK ABSORBER 2. Install: 3. Tighten: • Stopper ring (upper bearing) "1" • Adjuster "1" After installing the stopper ring, push back the bearing until it contacts the stopper ring. 3. Install: • Rear shock absorber 4. Adjust: 4. Install: •...
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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...
ELECTRICAL COMPONENTS AND WIRING DIAGRAM ELECTRICAL COMPONENTS AND WIRING DIAGRAM ELECTRICAL COMPONENTS Engine stop switch Ignition coil Spark plug CDI unit CDI magneto WIRING DIAGRAM Engine stop switch COLOR CODE CDI unit Black Ignition coil Orange CDI magneto Yellow Spark plug Black/Red Black/White Green/Blue...
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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 CHECKING THE ENGINE STOP Secondary Tester se- 1. Disconnect the spark plug cap SWITCH coil resis- lector posi- from spark plug. 1. Inspect: tance tion 2. Connect the dynamic spark tester • Engine stop switch conduction 5.7–8.5 "1"...
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IGNITION SYSTEM CHECKING THE CDI MAGNETO 3. Inspect: 1. Inspect: • Charging coil 2 resistance • Pickup coil resistance Out of specification → Replace. Out of specification → Replace. Tester (+) lead → Green/Blue lead Tester (+) lead → White/Red lead "1"...
ENGINE TUNING • Higher humidity reduces the amount of oxygen in the air by so ENGINE much of the water vapor in the CARBURETOR SETTING same air. • The role of fuel is to cool the engine, • Lower atmospheric pressure (at a and in the case of a 2-stroke en- high altitude) reduces the density of gine, to lubricate the engine in addi-...
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ENGINE ADJUSTING THE PILOT JET ADJUSTING THE JET NEEDLE Therefore, the fuel flow is balanced at The richness of air-fuel mixture with On the carburetors used in the each stage of throttle opening by a the throttle fully closed to 1/2 open YZ125, the main nozzle is a non dis- combination of the jet needle diame- can be set by changing the pilot jet...
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ENGINE CARBURETOR SETTING PARTS Part Jet nee- Main jet Part number Size number Size dle "4" "1" (-14143-) (-14116-) Rich #470 137-94 Rich 6BFY44-72 284-K2 #460 137-92 6BFY44-73 284-K3 #450 137-90 6BFY44-74 284-K4 #440 137-88 6BFY44-75 284-K5 (STD) #430 137-86 Lean 6BFY44-76 284-K6 #420...
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ENGINE ROAD CONDITION AND EXAMPLES OF CARBURETOR SETTING General condition Sandy condition Under 10°C 15–25°C Over 30°C Under 10°C 15–25°C Over 30°C (50°F) (59–77°F) (86°F) (50°F) (59–77°F) (86°F) (Winter) (Spring, Au- (Summer) (Winter) (Spring, Au- (Summer) tumn) tumn) Main jet #440 #430 #420...
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CHASSIS CHANGE OF THE HEAT RANGE <Requirement for selection of sec- OF SPARK PLUGS ondary gear reduction ratio> Judging from the discoloration of • It is generally said that the second- spark plugs, if they are found improp- ary gear ratio should be reduced for er, it can be corrected by the following a longer straight portion of a speed two methods;...
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CHASSIS REAR SUSPENSION SETTING The rear suspension setting should Generally a soft spring gives a soft Adjust the oil amount in 5 cm (0.2 be made depending on the rider's riding feeling. Rebound damping Imp oz, 0.2 US oz) increments or feeling of an actual run and the circuit tends to become stronger and the decrements.
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CHASSIS set length, replace the spring with REAR SHOCK ABSORBER an optional one and make readjust- SETTING PARTS Install the spring seat "2" to the ti- ment. • Rear shock spring "1" tanium spring. [Equal-pitch titanium spring] SPRING SPRI PART •...
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CHASSIS • Extent of adjustment (spring pre- load) SPRING PART Maximum Minimum NUMBER (-22212-) 1C3-00 1C3-10 Position 1C3-20 in which 1C3-30 the spring 5UN-00 is turned 5UN-A0 in 18 mm 5UN-B0 Position (0.71 in) 5UN-C0 in which from its 5UN-D0 the spring free 5UN-E0...
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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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PRINTED ON RECYCLED PAPER PRINTED IN JAPAN...