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. YZ125(D) q Leggere attentamente questo manuale prima di utilizzare questo veicolo.
1P8-9-36_cover 10.6.16 9:57 ページ 2 Q Read this manual carefully before operating this vehicle. This manual should stay with this vehicle if it is sold. Q 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. Q Bitte lesen Sie diese Bedienungsanleitung sorgfältig durch, bevor Sie das Fahrzeug in Betrieb nehmen. Diese Bedienungsanleitung muss, wenn das Fahrzeug verkauft wird, beim Fahrzeug verbleiben.
2013 Read this manual carefully before operating this vehicle.
YZ125 (D) OWNER'S SERVICE MANUAL ©2012 by Yamaha Motor Co., Ltd. 1st Edition, September 2012 All rights reserved.Any reprinting or unauthorized use without the written permission of Yamaha Motor Co., Ltd. is expressly prohibited.
FOREWORD INTRODUCTION Congratulations on your purchase of a Yamaha YZ series. This model is the culmination of Yamaha's vast experience in the production of pacesetting racing machines. It represents the highest grade of craftsmanship and reliability that have made Yamaha a leader. This manual explains operation, inspection, basic maintenance and tuning of your machine. If you have any questions about this manual or your machine, please contact your Yamaha dealer.
HOW TO USE THIS MANUAL FINDING THE REQUIRED PAGE 1. This manual consists of seven chapters; "General Information", "Specifications", "Regular inspection and adjustments", "Engine", "Chassis", "Electrical" and "Tuning" 2. The table of contents is at the beginning of the manual. Look over the general layout of the book before finding then required chapter and item. Bend the book at its edge, as shown, to find the required fore edge symbol mark and go to a page for required item and description.
HOW TO READ DESCRIPTIONS To help identify parts and clarify procedure steps, there are exploded diagrams at the start of each removal and disassembly section. 1. An easy-to-see exploded diagram "1" is provided for removal and disassembly jobs. 2. Numbers "2" are given in the or- 3 der of the jobs in the exploded diagram. A number that is enclosed by a circle indicates a disassembly step. 3. An explanation of jobs and notes is presented in an easy-to-read way by the use of symbol marks "3".
TABLE OF CONTENTS GENERAL INFORMATION 1 SPECIFICATIONS 2 REGULAR INSPECTION AND ADJUSTMENTS 3 ENGINE 4 CHASSIS 5 ELECTRICAL 6 TUNING 7
CONTENTS CHAPTER 1 GENERAL INFORMATION LOCATION OF IMPORTANT LABELS............................ 1-1 DESCRIPTION ................. 1-5 CONSUMER INFORMATION................. 1-6 INCLUDED PARTS .......... 1-6 IMPORTANT INFORMATION................. 1-6 CHECKING OF CONNECTION.................. 1-7 SPECIAL TOOLS ............. 1-8 CONTROL FUNCTIONS ................... 1-11 STARTING AND BREAK-IN ...................... 1-12 TORQUE-CHECK POINTS........................... 1-13 CLEANING AND STORAGE ....................
LOCATION OF IMPORTANT LABELS GENERAL INFORMATION LOCATION OF IMPORTANT LABELS Please read the following important labels carefully before operating this vehicle.
LOCATION OF IMPORTANT LABELS 1-2
LOCATION OF IMPORTANT LABELS EUROPE AUS, NZ, ZA 1-3
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. Measure tire pressure when tires are cold. Adjust tire pressure. Improper tire pressure can cause loss of control.
DESCRIPTION DESCRIPTION 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. Clutch lever Engine stop switch Front brake lever Throttle grip Radiator cap Fuel tank cap Kickstarter crank Fuel tank Radiator Coolant drain bolt Check bolt (Transmission oil level) Rear brake pedal Valve joint 14. 15. 16. 17. 18. 19. Fuel cock Air filter Drive chain Shift pedal Starter knob Front fork • The machine you have purchased may differ slightly from those shown in the following.
CONSUMER INFORMATION CONSUMER INFORMATION INCLUDED PARTS IMPORTANT INFORMATION There are two significant reasons for knowing the serial number of your machine: 1. When ordering parts, you can give the number to your Yamaha dealer for positive identification of the model you own. 2. If your machine is stolen, the authorities will need the number to search for and identify your machine. VEHICLE IDENTIFICATION NUMBER The vehicle identification number "1" is stamped on the right of the steering head pipe.
CHECKING OF CONNECTION 4. During the machine disassembly, clean all parts and place them in trays in the order of disassembly. This will speed up assembly time and help assure that all parts are correctly reinstalled. 5. Keep away from fire. ALL REPLACEMENT PARTS 1. We recommend to use Yamaha genuine parts for all replacements. Use oil and/or grease recommended by Yamaha for assembly and adjustment. GASKETS, OIL SEALS AND ORINGS 1.
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. Refer to the list provided to avoid errors when placing an order. • For U.S.A. and Canada, use part number starting with "YM-", "YU-" or "ACC-".
SPECIAL TOOLS Tool name/Part number How to use Fuel level gauge "1" YM-1312-A, 90890-01312 Fuel level gauge adaptor "2" YM-01470, 90890-01470 This gauge is used to measure the fuel level in the float chamber. Radiator cap tester YU-24460-01, 90890-01325 Radiator cap tester adapter YU-33984, 90890-01352 These tools are used for checking the cooling system. Flywheel puller YU-33270-B, 90890-01362 These tool is used to split the crankcase.
SPECIAL TOOLS Tool name/Part number How to use Fork seal driver YM-A0948, 90890-01502 This tool is used when install the fork oil seal. Spoke nipple wrench YM-01521, 90890-01521 This tool is used to tighten the spoke. Pocket tester YU-3112-C, 90890-03112 Use this tool to inspect the coil resistance, output voltage and amperage. Clutch holding tool YM-91042, 90890-04086 This tool is used to hold the clutch when removing or installing the clutch boss securing nut.
CONTROL FUNCTIONS CONTROL FUNCTIONS ENGINE STOP SWITCH The engine stop switch "1" is located on the left handlebar. Continue pushing the engine stop switch till the engine comes to a stop. CLUTCH LEVER The clutch lever "1" is located on the left handlebar; it disengages or engages the clutch. Pull the clutch lever to the handlebar to disengage the clutch, and release the lever to engage the clutch. The lever should be pulled rapidly and released slowly for smooth starts.
STARTING AND BREAK-IN STARTING AND BREAK-IN FUEL Mix oil with the gas at the ratio specified below. Always use fresh, namebrand gasoline, and mix the oil and gas the day of the race. Do not use premix that is more than a few hours old. Recommended fuel: Premium unleaded gasoline only with a research octane number of 95 or higher. If knocking or pinging occurs, use a different brand of gasoline or higher octane grade. Never mix two types of oil in the same batch; clotting of the oil could result.
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 Suspension Front Steering stem to front fork Rear For link type Front fork to upper bracket Front fork to lower bracket Assembly of lin
CLEANING AND STORAGE CLEANING AND STORAGE CLEANING Frequent cleaning of your machine will enhance its appearance, maintain good overall performance, and extend the life of many components. 1. Before washing the machine, block off the end of the exhaust pipe to prevent water from entering. A plastic bag secured with a rubber band may be used for this purpose. 2. If the engine is excessively greasy, apply some degreaser to it with a paint brush. Do not apply degreaser to the chain, sprockets, or wheel axles.
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) ← Overall height 1,315 mm (51.8 in) 1,318 mm (51.9 in) Seat height 997 mm (39.3in) 998 mm (39.3 in) Wheelbase 1,443 mm (56.8 in) ← Minimum ground clearance 386 mm (15.
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: 1st 2.385 (31/13) 2nd 1.933 (29/15) 3rd 1.588 (27/17) 4th 1.353 (23/17) 5th 1.200 (24/20) 6th 1.095 (23/21) Chassis: USA, AUS, ZA, NZ EUROPE, CDN Frame type Semi double cradle Caster angle 25.50 ° 25.60 ° Trail 105 mm (4.
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) 53.957–53.972 mm (2.1243–2.1249 in) ---- 17.5 mm (0.69 in) ---- Piston clearance 0.040–0.045 mmm (0.0016–0.0018 in) 0.1 mm (0.004 in) Piston offset 0.5 mm (0.019 in)/EX-side ---- 14.995–15.000 mm (0.5904–0.5906 in) 14.975 mm (0.5896 in) Plain ---- B=1.0 mm (0.039 in) ---- T=2.
MAINTENANCE SPECIFICATIONS Item Standard Limit Clutch: Friction plate thickness Quantity 2.9–3.1 mm (0.114–0.122 in) 2.8 mm (0.110 in) 8 ---- 1.5–1.7 mm (0.059–0.067 in) ---- Quantity 7 ---- Warp limit ---- 0.2 mm (0.008 in) 40.1 mm (1.579 in) 38.1 mm (1.500 in) 5 ---- Clutch plate thickness Clutch spring free length Quantity Clutch housing thrust clearance 0.15–0.26 mm (0.006–0.010 in) ---- Clutch housing radial clearance 0.01–0.04 mm (0.0006–0.
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) ---kg/cm2 Radiator cap opening pressure 95–125 kPa (0.95–1.25 Radiator capacity (total) 0.56 L (0.49 Imp qt, 0.59 US qt) ---- Single-suction centrifugal pump ---- , 13.5–17.
MAINTENANCE SPECIFICATIONS Item Standard Limit Swingarm: Swingarm free play limit End ---- 1.0 mm (0.04 in) Side clearance ---- 0.2–0.9 mm (0.008–0.035 in) Wheel: Front wheel type Spoke wheel ---- Rear wheel type Spoke wheel ---- Front rim size/material 21 × 1.60/Aluminum ---- Rear rim size/material 19 × 1.85/Aluminum ---- Radial ---- 2.0 mm (0.08 in) Lateral ---- 2.0 mm (0.
TIGHTENING TORQUES ELECTRICAL Item Standard Limit Ignition system: Ignition timing (B.T.D.C.) 0.48 mm (0.
TIGHTENING TORQUES Thread size Q'ty Tightening torque Radiator hose clamp M6 8 2 Nm (0.2 m•kg, 1.4 ft•lb) Air filter element M6 1 2 Nm (0.2 m•kg, 1.4 ft•lb) Item Remarks Carburetor joint M6 4 10 Nm (1.0 m•kg, 7.2 ft•lb) Carburetor joint clamp M4 1 2 Nm (0.2 m•kg, 1.4 ft•lb) Air filter joint clamp M4 1 2 Nm (0.2 m•kg, 1.4 ft•lb) Air filter case M6 4 8 Nm (0.8 m•kg, 5.8 ft•lb) Air filter guide clamp M5 1 4 Nm (0.4 m•kg, 2.9 ft•lb) Reed valve M3 6 1 Nm (0.1 m•kg, 0.
TIGHTENING TORQUES CHASSIS △ - marked portion shall be checked for torque tightening after break-in or before each race. Item Thread size Q'ty Tightening torque △ Upper bracket and outer tube M8 4 21 Nm (2.1 m•kg, 15 ft•lb) △ Lower bracket and outer tube M8 4 21 Nm (2.1 m•kg, 15 ft•lb) △ Upper bracket and steering stem M24 1 145 Nm (14.5 m•kg, 105 ft•lb) △ Handlebar upper holder M8 4 28 Nm (2.8 m•kg, 20 ft•lb) △ Handlebar lower holder M12 2 40 Nm (4.
TIGHTENING TORQUES Thread size Q'ty Tightening torque Footrest bracket and frame M10 4 55 Nm (5.5 m•kg, 40 ft•lb) △ Brake pedal mounting M8 1 26 Nm (2.6 m•kg, 19 ft•lb) △ Rear brake master cylinder and frame M6 2 10 Nm (1.0 m•kg, 7.2 ft•lb) Rear brake master cylinder cap M4 2 2 Nm (0.2 m•kg, 1.4 ft•lb) Rear brake hose union bolt (caliper) M10 1 30 Nm (3.0 m•kg, 22 ft•lb) Copper washer △ Rear brake hose union bolt (master cylinder) M10 1 30 Nm (3.
TIGHTENING TORQUES Item Thread size Q'ty Tightening torque △ Rear fender (front) M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb) △ Rear fender (rear) M6 2 12 Nm (1.2 m•kg, 8.7 ft•lb) △ Side cover M6 2 7 Nm (0.7 m•kg, 5.1 ft•lb) Seat M8 2 19 Nm (1.9 m•kg, 13 ft•lb) Number plate M6 1 7 Nm (0.7 m•kg, 5.1 ft•lb) △ Remarks 1. First, tighten the steering ring nut approximately 38 Nm (3.8 m•kg, 27 ft•lb) by using the steering nut wrench, then loosen the steering ring nut one turn. 2.
TIGHTENING TORQUES GENERAL TORQUE SPECIFICATIONS This chart specifies torque for standard fasteners with standard I.S.O. pitch threads. Torque specifications for special components or assemblies are included in the applicable sections of this book. To avoid warpage, tighten multi-fastener assemblies in a crisscross fashion, in progressive stages, until full torque is reached. Unless otherwise specified, torque specifications call for clean, dry threads. Components should be at room temperature.
CABLE ROUTING DIAGRAM CABLE ROUTING DIAGRAM 1. 2. 3. 4. 5. 6. 7. 8. 9. Engine stop switch lead Throttle cable Clutch cable Ground lead High tension cord Clamp Air vent hose Radiator breather hose CDI magneto lead 10. 11. 12. 13. 14. 15. A. YPVS breather hose Engine bracket (right) Engine bracket (left) Crankcase breather hose Overflow hose Connector cover Pass the clutch cable on the outside of the throttle cable and engine stop switch lead. 2-13 B. C.
CABLE ROUTING DIAGRAM D. E. F. G. H. I. J. K. L. M. N. O. P. 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. Clamp the clutch cable below the positioning grommet. Pass the air vent hose back of the throttle cable.
CABLE ROUTING DIAGRAM 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. High tension cord Engine stop switch lead Ignition coil lead Clamp CDI unit CDI unit band Radiator breather hose CDI magneto lead Connector cover Throttle cable Clutch cable 12. CDI unit stay A. Pass the high tension cord to the left of the radiator hose. B. Using a plastic locking tie, clamp the engine stop switch lead, ignition coil lead and CDI magneto lead together with the clamp ends backward and then cut off the tie end. 2-15 C.
CABLE ROUTING DIAGRAM D. E. F. G. H. I. 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 arrowed range. Insert the CDI unit band until it stops at the CDI unit stay. Pass the CDI magneto lead and radiator breather hose between the frame and the radiator hose so that they come within the arrow-indicated range.
CABLE ROUTING DIAGRAM 1. 2. 3. A. B. Master cylinder Brake hose holder Brake hose Install the brake hose so that its pipe portion directs as shown and lightly touches the projection on the caliper. Pass the brake hose into the brake hose holders. C. D. If the brake hose contacts the spring (rear shock absorber), correct its twist. Install the brake hose so that its pipe portion directs as shown and lightly touches the projection on the master cylinder.
CABLE ROUTING DIAGRAM n) 5i 5 (0. n) 7i 4 (0. 1. 2. 3. 4. 5. 6. 7. 8. Brake hose Master cylinder Engine stop switch lead Engine stop switch Throttle cable Clutch cable Clamp Cable guide A. B. C. Install the brake hose so that its pipe portion directs as shown and lightly touches the projection on the master cylinder. Pass the engine stop switch lead in the middle of the clutch holder. Clamp the engine stop switch lead to the handlebar. 2-18 D. E.
MAINTENANCE INTERVALS REGULAR INSPECTION AND ADJUSTMENTS MAINTENANCE INTERVALS • 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.
MAINTENANCE INTERVALS Item After break-in Every race (about 2.5 hours) Every third (about 7.5 hours) Every fifth (about 12.5 hours) As required Remarks ROTOR NUT Retighten ● ● MUFFLER Inspect ● ● Clean Retighten ● ● ● Replace fiber ●* * When the exhaust sound becomes louder or when a performance drop is felt.
MAINTENANCE INTERVALS After break-in Every race (about 2.5 hours) Adjust lever position and pedal height ● ● Lubricate pivot point ● ● Check brake disc surface ● ● Check fluid level and leakage ● ● Retighten brake disc bolts, caliper bolts, master cylinder bolts and union bolts ● ● Item Every third (about 7.5 hours) Every fifth (about 12.
MAINTENANCE INTERVALS After break-in Every race (about 2.5 hours) Inspect air pressure, wheel run-out, tire wear and spoke looseness ● ● Retighten sprocket bolt ● ● Item Every third (about 7.5 hours) Every fifth (about 12.
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 Coolant Check that coolant is filled up to the radiator cap. Check the cooling system for leakage. P.3-6 – 7 Fuel Check that a fresh mixture of oil and gasoline is filled in the fuel tank.
ENGINE ENGINE CHECKING THE COOLANT LEVEL Do not remove the radiator cap "1", drain bolt and hoses when the engine and radiator are hot. Scalding hot fluid and steam may be blown out under pressure, which could cause serious injury. When the engine has cooled, place a thick towel over the radiator cap, slowly rotate the cap counterclockwise to the detent. This procedure allows any residual pressure to escape.
ENGINE 3. Radiator cap 2. Apply the specified pressure. Radiator cap opening pressure: 95–125 kPa (0.95–1.25 kg/cm2, 13.5–17.8 psi) 3. Inspect: • Pressure Impossible to maintain the specified pressure for 10 seconds → Replace. CHECKING THE COOLING SYSTEM 1. Inspect: • Coolant level 2. Attach: • Radiator cap tester "1" and adapter "2" Radiator cap tester: YU-24460-01/9089001325 Radiator cap tester adapter: YU-33984/90890-01352 ADJUSTING THE CLUTCH LEVER FREE PLAY 1.
ENGINE LUBRICATING THE THROTTLE 1. Remove: • Cap cover "1" • Throttle cable cap "2" 2. Clean: • Air filter element Clean them with solvent. After cleaning, remove the remaining solvent by squeezing the element. 2. Apply: • Lithium soap base grease On the throttle cable end "a", tube guide cable winding portion "b" and roller sliding surface "c". • Do not twist the element when squeezing the element. • Leaving too much of solvent in the element may result in poor starting. 3.
CHASSIS c. Inspect the gasket (oil check bolt), replace if damaged. d. Tighten the oil check bolt. Oil check bolt: 10 Nm (1.0 m•kg, 7.2 ft•lb) CHANGING THE TRANSMISSION OIL 1. Start the engine and warm it up for several minutes and wait for five minute. 2. Place the machine on a level place and hold it on upright position by placing the suitable stand under the engine. 3. Place a suitable container under the engine. 4. Remove: • Oil drain bolt "1" • Oil filler cap "2" Drain the transmission oil. 6.
CHASSIS ADJUSTING THE FRONT BRAKE 1. Check: • Brake lever position "a" Brake lever position "a": d. e. f. g. h. A. Front B. Rear Place the other end of the tube into a container. Slowly apply the brake lever or pedal several times. Pull the lever in or push down on the pedal. Hold the lever or pedal in position. Loosen the bleed screw and allow the lever or pedal to travel towards its limit. Tighten the bleed screw when the lever or pedal limit has been reached; then release the lever or pedal.
CHASSIS g. Tighten the bleed screw. Bleed screw: 6 Nm (0.6 m•kg, 4.3 ft•lb) h. Install the brake pads "7" and pad pin. 2. Replace: • Brake pad Brake pad replacement steps: a. Remove the pad pin plug "1". b. Loosen the pad pin "2". c. Remove the brake caliper "3" from the front fork. • Install the brake pads with their projections "a" into the brake caliper recesses "b". • Temporarily tighten the pad pin at this point. i. Install the brake caliper "8" and tighten the pad pin "9".
CHASSIS e. Connect the transparent hose "8" to the bleed screw "9" and place the suitable container under its end. f. k. Install the pad pin plug "15" and protector "16". Pad pin plug: 3 Nm (0.3 m•kg, 2.2 ft•lb) Bolt (protector): 7 Nm (0.7 m•kg, 5.1 ft•lb) Loosen the bleed screw and push the brake caliper piston in. • Use only designated quality brake fluid to avoid poor brake performance. • Refill with same type and brand of brake fluid; mixing fluids could result in poor brake performance.
CHASSIS 6. Lubricate: • Drive chain Drive chain lubricant: SAE 10W-40 motor oil or suitable chain lubricants 2. • • • Remove: Master link clip Joint "1" Drive chain "2" 3. Clean: • Drive chain Place it in kerosene, and brush off as much dirt as possible. Then remove the drive chain from the kerosene and dry the drive chain. ADJUSTING THE DRIVE CHAIN SLACK 1. Elevate the rear wheel by placing the suitable stand under the engine. 2. Check: • Drive chain slack "a" Above the seal guard installation bolt.
CHASSIS CLEANING THE FRONT FORK OIL SEAL AND DUST SEAL 1. Remove: • Protector • Dust seal "1" Use a thin screw driver, and be careful not to damage the inner fork tube and dust seal. ADJUSTING THE FRONT FORK REBOUND DAMPING FORCE 1. Adjust: • Rebound damping force By turning the adjuster "1". Stiffer "a" → Increase the rebound damping force. (Turn the adjuster "1" in.) Softer "b" → Decrease the rebound damping force. (Turn the adjuster "1" out.
CHASSIS 3. Measure: • Spring fitting length Extent of adjustment: Maximum Standard fitting length: I.D. MARK/ Q'TY Red/1 Red/2 Red/3 Fully turned in position Length 258 mm (10.16 in) *252 mm (9.92 in) 264 mm (10.39 in) *258 mm (10.16 in) 255.5 mm (10.06 in) *249.5 mm (9.82 in) *For EUROPE Minimum 20 clicks out (from maximum position) Extent of adjustment: Maximum Minimum Position in which the spring is turned in 18 mm (0.71 in) from its free length Position in which the spring is turned in 1.
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: This is the position which is back by the specific number of clicks from the fully turned-in position. (Which align the punch mark "a" on the adjuster with the punch mark "b" on the high compression damping adjuster.
CHASSIS CHECKING AND ADJUSTING THE STEERING HEAD 1. Place a stand under the engine to raise the front wheel off the ground. WARNING! Securely support the vehicle so that there is no danger of it falling over. 2. Check: • Steering stem Grasp the bottom of the forks and gently rock the fork assembly back and forth. Free play → Adjust steering head. 3. Check: • Steering smooth action Turn the handlebar lock to lock. Unsmooth action → Adjust steering ring nut.
CHASSIS LUBRICATION To ensure smooth operation of all components, lubricate your machine during setup, after break-in, and after every race. 1. All control cable 2. Clutch lever pivot 3. Shift pedal pivot 4. Footrest pivot 5. Throttle-to-handlebar contact 6. Drive chain 7. 8. 9. Throttle roller cable guide Throttle roller sliding surface Tube guide cable winding portion 10. Throttle cable end 11. Clutch cable end A. Use Yamaha cable lube or equivalent on these areas. B.
ELECTRICAL ELECTRICAL CHECKING THE SPARK PLUG 1. Remove: • Spark plug 2. Inspect: • Electrode "1" Wear/damage → Replace. • Insulator color "2" Normal condition is a medium to light tan color. Distinctly different color → Check the engine condition. When the engine runs for many hours at low speeds, the spark plug insulator will become sooty, even if the engine and carburetor are in good operating condition. 3. Measure: • Plug gap "a" Use a wire gauge or thickness gauge. Out of specification → Regap.
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 requested not to undertake inspection, adjustment, disassembly, or reassembly only by reference to this manual. It may lead to servicing trouble and mechanical damage.
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 remove it because its claws "a" are inserted in the air filter case. REMOVING THE NUMBER PLATE 1. Remove: • Bolt (number plate) • Number plate "1" • The projection "a" is inserted into the band of the number plate. Pull the band off the projection before removal. • Remove the clutch cable "2" from the cable guide "b" on the number plate.
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 Q'ty Remarks Refer to "SEAT, FUEL TANK AND SIDE COVERS" section. Right side cover 1 Bolt (silencer) 2 2 Washer [ø=26 mm (1.02 in)] 1 3 Washer [ø=22 mm (0.87 in)] 1 4 Silencer 1 5 Collar [L=15.5 mm (0.61 in)] 1 6 Collar [L=13.5 mm (0.
EXHAUST PIPE AND SILENCER CHANGING THE SILENCER FIBER 1. Remove: • Side cover (right) • Bolt (silencer) "1" • Silencer "2" • Bolt (fiber) "3" 2. • 3. • Remove: Inner pipe "1" Replace: 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) • Silencer "2" • Bolt [silencer (front)] "3" Bolt [silencer (front)] : 12 Nm (1.2 m•kg, 8.
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 Remarks Drain the coolant. Refer to "CHANGING THE COOLANT" section in the CHAPTER 3. Seat and fuel tank Refer to "SEAT, FUEL TANK AND SIDE COVERS" section.
RADIATOR HANDLING NOTE Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may be blown out under pressure, which could cause serious injury. When the engine has cooled, open the radiator cap by the following procedure: Place a thick rag, like a towel, over the radiator cap, slowly rotate the cap counterclockwise to the detent. This procedure allows any residual pressure to escape.
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 Remarks Refer to "SEAT, FUEL TANK AND SIDE COVERS" section. Fuel tank 1 Clamp (carburetor joint) 2 2 Carburetor 1 3 Carburetor joint 1 4 Reed valve assembly 1 5 Stopper (reed valve) 2 6 Reed valve 2 4-7 Loosen the screw (carburetor joint).
CARBURETOR AND REED VALVE DISASSEMBLING THE CARBURETOR 4 Nm (0.4 m kg, 2.9 ft lb) Order Part name Q'ty 1 Mixing chamber top 1 2 Throttle valve 1 3 Needle holder 1 4 Jet needle 1 5 Float chamber 1 6 Needle jet cover 1 7 Float pin 1 8 Float 1 9 Valve seat 1 10 Main jet 1 11 Main jet holder 1 12 Pilot jet 1 13 Starter plunger 1 14 Throttle stop screw 1 15 Pilot air screw 1 4-8 Remarks Refer to removal section.
CARBURETOR AND REED VALVE HANDLING NOTE CHECKING THE JET NEEDLE 1. Inspect: • Jet needle "1" Bends/wear → Replace. • Clip groove Free play exists/wear → Replace. • Clip position Do not disassemble the venturi block "1" and main nozzle "2" because it will cause a drop in carburetor performance. 2. • • • REMOVING THE THROTTLE VALVE 1.
CARBURETOR AND REED VALVE d. Measure the fuel level with the fuel level gauge. Keep the carburetor and fuel level gauge vertically when measuring the fuel level. e. If the fuel level is not within specification, inspect the valve seat and needle valve. f. If either is worn, replace them both. g. If both are fine, adjust the fuel level by bending the float tab "b" on the float. h. Recheck the fuel level. 2. Measure: • Valve stopper height "a" Out of specification → Adjust stopper/Replace valve stopper.
CARBURETOR AND REED VALVE • After installing the needle valve to the float, install them to the carburetor. • Check the float for smooth movement. 2. Tighten: • Bolt (air filter joint) "1" Bolt (air filter joint): 2 Nm (0.2 m•kg, 1.4 ft•lb) 5. • • • Install: Float chamber "1" Plate "2" Screw (float chamber) "3" • Bolt (carburetor joint) "2" 8. Install: • Mixing chamber top "1" • Screw (mixing chamber top) "2" To carburetor "3". Bolt (carburetor joint): 2 Nm (0.2 m•kg, 1.
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) 5 Nm (0.5 m kg, 3.6 ft lb) Order Part name Q'ty Remarks Seat and fuel tank Refer to "SEAT, FUEL TANK AND SIDE COVERS" section. Exhaust pipe and silencer Refer to "EXHAUST PIPE AND SILENCER" section.
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 Remarks 1 Piston pin clip 2 Refer to removal section. 2 Piston pin 1 Refer to removal section. 3 Piston 1 Refer to removal section. 4 Small end bearing 1 Refer to removal section. 5 Piston ring 1 Refer to removal section.
CYLINDER HEAD, CYLINDER AND PISTON REMOVING THE PUSH ROD 1. Remove: • Bolt (push rod) "1" • Push rod "2" Set the collar "3" included in owner's tool kit to remove the bolt (push rod). REMOVING THE PISTON AND PISTON RING 1. Remove: • Piston pin clip "1" Before removing the piston pin clip, cover the crankcase with a clean rag to prevent the piston pin clip from falling into the crankcase cavity. 2.
CYLINDER HEAD, CYLINDER AND PISTON Standard Wear limit 54.000– Cylin54.014 mm der bore (2.1260– "C" 2.1265 in) 54.1 mm (2.130 in) Taper "T" — 0.05 mm (0.0020 in) "C" = Maximum Aa–Cb "T" = (Maximum Aa, or Ab) - (Maximum Ba, or Bb) CHECKING THE PISTON PIN AND SMALL END BEARING 1. Inspect: • Piston pin • Small end bearing Signs of heat discoloration → Replace. 2. Measure: • Piston pin outside diameter Use micrometer "1". Out of specification → Replace.
CYLINDER HEAD, CYLINDER AND PISTON • Collar "5" Wear/Damage → Replace. • Spring "6" Broken → Replace. 2. Check: • Piston mark "a" CHECKING THE PISTON CLEARANCE 1. Calculate: • Piston clearance Out of specification → Replace piston, and piston ring and/or cylinder. Refer to "Cylinder" and "Piston". Piston mark "a" (color) Piston size A (red) 53.957–53.960 mm (2.1243–2.1244 in) B (orange) 53.961–53.964 mm (2.1244–2.1246 in) C (green) 53.965–53.968 mm (2.1246–2.1247 in) D (purple) 53.969–53.
CYLINDER HEAD, CYLINDER AND PISTON • Before installing the piston pin clip, cover the crankcase with a clean rag to prevent the piston pin clip from falling into the crankcase cavity. • Install the spring to the link lever, and then to the cylinder. • Install the spring with its stopper portion "a" facing inward. • Apply the lithium soap base grease on the oil seal lip. INSTALLING THE PISTON RING AND PISTON 1. Install: • Piston ring "1" 3.
CYLINDER HEAD, CYLINDER AND PISTON 3. Install: • Nut (cylinder) "1" 9. Install: • Spark plug "1" Spark plug: 20 Nm (2.0 m•kg, 14 ft•lb) Nut (cylinder): 30 Nm (3.0 m•kg, 22 ft•lb) • Spark plug cap "2" Tighten the nuts in stage, using a crisscross pattern. 6. Install: • O-ring "1" Apply the lithium soap base grease on the O-rings. 4. • • • • Install: Collar "1" Push rod "2" Plain washer "3" Bolt (push rod) "4" Bolt (push rod): 5 Nm (0.5 m•kg, 3.
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 Drain the transmission oil. Refer to "CHANGING THE TRANSMISSION OIL" section in the CHAPTER 3. Bolt (brake pedal) Shift the brake pedal downward. Rotor and stator Refer to "CDI MAGNETO" section. Clutch cable Disconnect at engine side.
CLUTCH REMOVING THE CLUTCH BOSS 80 Nm (8.0 m kg, 58 ft lb) Order Part name Q'ty Remarks 1 Push rod 1 1 2 Circlip 1 3 Washer 1 4 Bearing 1 5 Ball 1 6 Push rod 2 1 7 Nut (clutch boss) 1 Refer to removal section. 8 Lock washer 1 Refer to removal section. 9 Clutch boss 1 Refer to removal section. 10 Thrust washer [D=ø34 mm (1.34 in)] 1 11 Primary driven gear 1 12 Bearing 1 13 Thrust washer [D=ø34 mm (1.
CLUTCH REMOVING THE CLUTCH BOSS 1. Remove: • Nut "1" • Lock washer "2" • Clutch boss "3" Straighten the lock washer tab and use the clutch holding tool "4" to hold the clutch boss. Clutch holding tool: YM-91042/90890-04086 CHECKING THE CLUTCH SPRINGS 1. Measure: • Clutch spring free length "a" Out of specification → Replace springs as a set. Clutch spring free length "a": 40.1 mm (1.579 in) : 38.1 mm (1.500 in) CHECKING THE FRICTION PLATES 1.
CLUTCH 5. Install: • Friction plate "1" • Clutch plate "2" 2. Install: • Thrust washer [D=ø34 mm (1.34 in)] "1" • Clutch boss "2" 3. Install: • Lock washer "1" • Nut (clutch boss) "2" Nut (clutch boss): 80 Nm (8.0 m•kg, 58 ft•lb) • Install the clutch plates and friction plates alternately on the clutch boss, starting with a friction plate and ending with a friction plate. • Apply the transmission oil on the friction plates and clutch plates. 6.
KICK SHAFT AND SHIFT SHAFT KICK SHAFT AND SHIFT SHAFT REMOVING THE PRIMARY DRIVE GEAR Order Part name Q'ty Remarks Drain the transmission oil. Refer to "CHANGING THE TRANSMISSION OIL" section in the CHAPTER 3. Clutch cable Disconnect at engine side. Bolt (brake pedal) Shift the brake pedal downward. Radiator hose 4 Disconnect at water pump side. Bolt (push rod) Refer to "CYLINDER HEAD, CYLINDER AND PISTON" section.
KICK SHAFT AND SHIFT SHAFT REMOVING THE KICK SHAFT AND SHIFT SHAFT Order Part name Q'ty Remarks 1 Kick idle gear 1 2 Kick shaft assembly 1 3 Shift pedal 1 4 Shift shaft 1 5 Roller 1 6 Shift guide 1 Refer to removal section. 7 Shift lever assembly 1 Refer to removal section. 8 Stopper lever 1 4-24 Refer to removal section.
KICK SHAFT AND SHIFT SHAFT REMOVING THE PRIMARY DRIVE GEAR 1. Loosen: • Bolt (primary drive gear) "1" Place an aluminum plate "a" between the teeth of the primary drive gear "2" and driven gear "3". REMOVING THE KICK SHAFT ASSEMBLY 1. Remove: • Kick shaft assembly "1" Unhook the torsion spring "2" from the hole "a" in the crankcase. REMOVING THE SHIFT GUIDE AND SHIFT LEVER ASSEMBLY 1.
KICK SHAFT AND SHIFT SHAFT INSTALLING THE SEGMENT 1. Install: • Segment "1" • Bolt (segment) Bolt (segment): 30 Nm (3.0 m•kg, 22 ft•lb) INSTALLING THE SHIFT GUIDE AND SHIFT LEVER ASSEMBLY 1. Install: • Spring "1" • Pawl pin "2" • Pawl "3" To shift lever "4". INSTALLING THE SHIFT SHAFT 1. Install: • Roller "1" • Shift shaft "2" Apply the transmission oil on the roller and shift shaft. Align the notch "a" on the segment with the pin "b" on the shift cam. If the segment gets an impact, it may be damaged.
KICK SHAFT AND SHIFT SHAFT 3. Install: • Kick shaft assembly "1" • Apply the transmission oil on the kick shaft. • Slide the kick shaft assembly into the crankcase, make sure the clip "2" and kick shaft stopper "a" fit into their home position "b", "c". Tighten the bolts in stage, using a crisscross pattern. 2. Install: • Primary driven gear Refer to "CLUTCH" section. 3. Tighten: • Bolt (primary drive gear) "1" Bolt (primary drive gear): 48 Nm (4.8 m•kg, 35 ft•lb) 4.
YPVS GOVERNOR YPVS GOVERNOR REMOVING THE YPVS GOVERNOR Order Part name Q'ty Remarks Refer to "KICK SHAFT AND SHIFT SHAFT" section. Right crankcase cover 1 Governor assembly 1 2 Dowel pin 1 3 Retainer 1 4 Ball 4 5 Retainer weight 1 6 Plain washer 3 7 Thrust bearing 2 8 Collar 1 9 Plate 1 10 Compression spring 1 11 Governor gear 1 12 Governor shaft 1 4-28 Refer to removal section.
YPVS GOVERNOR REMOVING THE GOVERNOR 1. Remove: • Dowel pin "1" While compressing the spring, remove the dowel pin. CHECKING THE GOVERNOR GROOVE 1. Inspect: • Washer "1" • Collar "2" Wear/Damage → Replace. 2. Install: • Ball "1" • Retainer "2" To governor shaft "3". Apply the transmission oil on the retainer and ball. CHECKING THE BEARING 1. Inspect: • Thrust bearing "1" • Washer "2" Wear/Damage → Replace. 3. Install: • Dowel pin "1" • While compressing the spring, install the dowel pin.
WATER PUMP WATER PUMP DISASSEMBLING THE WATER PUMP Order Part name Q'ty Remarks Refer to "KICK SHAFT AND SHIFT SHAFT" section. Crankcase cover (right) 1 Water pump housing cover 1 2 Impeller shaft gear 1 3 Dowel pin 1 4 Plain washer 1 5 Impeller shaft assembly 1 6 Bearing 1 Refer to removal section. 7 Oil seal 2 Refer to removal section.
WATER PUMP REMOVING THE OIL SEAL • Replace the oil seal when transmission oil or coolant leaks out from the water pump housing hole at the bottom. • Do not reuse the removed bearing and oil seal. CHECKING THE BEARING 1. Inspect: • Bearing "1" Rotate inner race with a finger. Rough spot/seizure → Replace. INSTALLING THE IMPELLER SHAFT 1. Install: • Impeller shaft "1" • Take care so that the oil seal lip is not damaged or the spring does not slip off its position.
WATER PUMP 4. Install: • Water pump housing cover "1" • Bolt (water pump housing cover) "2" Bolt (water pump housing cover): 10 Nm (1.0 m•kg, 7.2 ft•lb) • Copper washer (coolant drain bolt) "3" • Coolant drain bolt "4" Coolant drain bolt: 10 Nm (1.0 m•kg, 7.
CDI MAGNETO CDI MAGNETO REMOVING THE CDI MAGNETO Order Part name Q'ty Remarks Seat and fuel tank Refer to "SEAT, FUEL TANK AND SIDE COVERS" section. Bolt (Radiator) Refer to "RADIATOR" section. Disconnect the CDI magneto lead. 1 Left crankcase cover 1 2 Nut (rotor) 1 Refer to removal section. 3 Rotor 1 Refer to removal section.
CDI MAGNETO REMOVING THE ROTOR 1. Remove: • Nut (rotor) "1" • Washer "2" Use the rotor holding tool "3". Rotor holding tool: YU-1235/90890-01235 INSTALLING THE CDI MAGNETO 1. Install: • Stator "1" • Screw (stator) "2" 4. Adjust: • Ignition timing Refer to "CHECKING THE IGNITION TIMING" section in the CHAPTER 3. Temporarily tighten the screws (stator) at this point. Ignition timing (B.T.D.C): 0.48 mm (0.019 in) 5. Tighten: • Screw (stator) "1" Screw (stator): 7 Nm (0.7 m•kg, 5.1 ft•lb) 2.
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 Part name Q'ty Remarks Hold the machine by placing the suitable stand under the engine. Refer to "HANDLING NOTE". Seat and fuel tank Refer to "SEAT, FUEL TANK AND SIDE COVERS" section. Carburetor Refer to "CARBURETOR AND REED VALVE" section.
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 Part name Q'ty 7 Brake pedal 1 8 Engine bracket 2 Remarks 9 Engine mounting bolt 3 10 Pivot shaft 1 Refer to removal section. 11 Engine 1 Refer to removal section.
ENGINE REMOVAL HANDLING NOTE Support the machine securely so there is no danger of it falling over. REMOVING THE DRIVE SPROCKET 1. Remove: • Nut (drive sprocket) "1" • Lock washer "2" • Straighten the lock washer tab. • Loosen the nut while applying the rear brake. INSTALLING THE ENGINE 1. Install: • Engine "1" Install the engine from right side. • Pivot shaft "2" • Nut (pivot shaft) "3" Nut (Pivot shaft): 85 Nm (8.
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. Install: • Drive chain sprocket guide "1" • Drive chain sprocket cover "2" • Screw (drive chain sprocket cover) "3" Screw (drive chain sprocket cover): 5 Nm (0.5 m•kg, 3.
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 Remarks Engine Refer to "ENGINE REMOVAL" section. Piston Refer to "CYLINDER HEAD, CYLINDER AND PISTON" section. Primary drive gear Refer to "KICK SHAFT AND SHIFT SHAFT" section. Kick idle gear Refer to "KICK SHAFT AND SHIFT SHAFT" section.
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 9 Crankshaft 1 10 Oil seal 2 11 Bearing 2 4-40 Remarks Refer to removal section. Refer to removal section.
CRANKCASE AND CRANKSHAFT REMOVING THE SEGMENT 1. Remove: • Bolt (segment) "1" • Segment "2" Turn the segment counterclockwise until it stops and loosen the bolt. If the segment gets an impact, it may be damaged. Take care not to give an impact to the segment when removing the bolt. REMOVING THE CRANKSHAFT 1. Remove: • Crankshaft "1" Use the crankcase separating tool "2". Crankcase separating tool: YU-1135-A/9089001135 CHECKING THE CRANKCASE 1. Inspect: • Contacting surface "a" Scratches → Replace.
CRANKCASE AND CRANKSHAFT Standard Runout limit: 0.03 mm (0.0012 in) 0.05 mm (0.002 in) Small end free play: 0.8–1.0 mm (0.031– 0.039 in) 2.0 mm (0.08 in) Side clearance: 0.06–0.64 mm (0.002– 0.025 in) — Crack width: 55.90–55.95 mm (2.201– 2.203 in) — INSTALLING THE CRANKCASE BEARING 1. Install: • Bearing "1" To left and right crankcase. Install the bearing by pressing its outer race parallel. 2. Check: • Shifter operation • Transmission operation Unsmooth operation → Repair.
CRANKCASE AND CRANKSHAFT • Apply molybdenum disulfide grease to the surface "a" where the crankshaft and bearing come in contact. • Use two plain washers (Yamaha genuine: 90201-243K3) "5" or the ones of a size as shown one on the other. (Except for USA and CDN) • Install so that the plain washers do not deviate from the crankshaft center. (Except for USA and CDN) • When installing the crankcase, the connecting rod should be positioned at TDC (top dead center).
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" section. Separate the crankcase. Refer to "CRANKCASE AND CRANKSHAFT" section. 1 Guide bar (long) 1 2 Guide bar (short) 1 3 Shift cam 1 4 Shift fork 3 1 5 Shift fork 1 1 6 Shift fork 2 1 7 Main axle 1 Refer to removal section.
TRANSMISSION, SHIFT CAM AND SHIFT FORK REMOVING THE TRANSMISSION 1. Remove: • Main axle "1" • Drive axle "2" • Tap lightly on the transmission drive axle with a soft hammer to remove. • Remove assembly carefully. Note the position of each part. Pay particular attention to the location and direction of shift forks. CHECKING THE SHIFT FORK, SHIFT CAM AND SEGMENT 1. Inspect: • Shift fork "1" Wear/damage/scratches → Replace. 2. • • • Inspect: Shift cam "1" Segment "2" Guide bar "3" Wear/damage → Replace.
TRANSMISSION, SHIFT CAM AND SHIFT FORK 4. Check: • Shifter operation • Transmission operation Unsmooth operation → Repair. 4. Install: • Collar "1" 2. Install: • Shift cam "1" • Apply the lithium soap base grease on the oil seal lip. • When installing the collar into the crankcase, pay careful attention to the crankcase oil seal lip. • Apply the transmission oil on the shift cam.
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 requested not to undertake inspection, adjustment, disassembly, or reassembly only by reference to this manual. It may lead to servicing trouble and mechanical damage.
FRONT WHEEL AND REAR WHEEL REMOVING THE REAR WHEEL Order Part name Q'ty Hold the machine by placing the suitable stand under the engine. Refer to "HANDLING NOTE". 1 Nut (rear wheel axle) 1 2 Rear wheel axle 1 3 Drive chain puller 2 4 Rear wheel 1 5 Collar 2 6 Rear wheel sprocket 1 7 Oil seal 2 8 Circlip 1 9 Bearing 2 10 Brake disc 1 5-2 Remarks Refer to removal section. 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" Push the wheel forward and remove the drive chain "2". CHECKING THE WHEEL AXLE 1. Measure: • Wheel axle bends Out of specification → Replace. Use the dial gauge "1". Wheel axle bending limit: 0.5 mm (0.020 in) The bending value is shown by one half of the dial gauge reading. REMOVING THE WHEEL BEARING 1.
FRONT WHEEL AND REAR WHEEL 2. Install: • Brake disc "1" • Bolt (brake disc) "2" Bolt (brake disc): 12 Nm (1.2 m•kg, 8.7 ft•lb) 6. Install: • Nut (wheel axle) "1" Nut (wheel axle): 105 Nm (10.5 m•kg, 75 ft•lb) Do not strike the inner race of the bearing. Contact should be made only with the outer race. Tighten the bolts in stage, using a crisscross pattern. 7. Tighten: • Bolt (axle holder) "1" 3. Install: • Collar "1" • Apply the lithium soap base grease on the oil seal lip.
FRONT WHEEL AND REAR WHEEL 4. Install: • Collar "1" Apply the lithium soap base grease on the oil seal lip. 8. • • • Install: Right drive chain puller "1" Washer "2" Nut (wheel axle) "3" Temporarily tighten the nut (wheel axle) at this point. 5. Install: • Wheel Install the brake disc "1" between the brake pads "2" correctly. 9. Adjust: • Drive chain slack "a" Drive chain slack "a": 48–58 mm (1.9–2.3 in) Refer to "ADJUSTING THE DRIVE CHAIN SLACK" section in the CHAPTER 3. 6.
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 under the engine. Refer to "HANDLING NOTE". Drain the brake fluid. Refer to removal section. 1 Brake hose holder (protector) 2 2 Union bolt 2 3 Brake hose 1 4 Pad pin plug 1 Remove when loosening the pad pin. 5 Pad pin 1 Loosen when disassembling the brake caliper.
FRONT BRAKE AND REAR BRAKE REMOVING THE REAR BRAKE Order Part name Q'ty Remarks Hold the machine by placing the suitable stand under the engine. Refer to "HANDLING NOTE". Rear wheel Refer to "FRONT WHEEL AND REAR WHEEL" section. Drain the brake fluid. Refer to removal section. 1 Brake pedal 1 2 Brake master cylinder 1 3 Brake hose holder 2 4 Union bolt 2 5 Brake hose 1 6 Pad pin plug 1 Remove when loosening the pad pin. Loosen when disassembling the brake caliper.
FRONT BRAKE AND REAR BRAKE DISASSEMBLING THE BRAKE CALIPER Order Part name Q'ty Remarks A. B. A B 1 Pad pin 1 1 2 Brake pad 2 2 3 Pad support 1 1 Front Rear 4 Brake caliper piston 2 1 Refer to removal section. 5 Brake caliper piston dust seal 2 1 Refer to removal section. 6 Brake caliper piston seal 2 1 Refer to removal section.
FRONT BRAKE AND REAR BRAKE DISASSEMBLING THE BRAKE MASTER CYLINDER Order Part name Q'ty Remarks A. B. 1 Brake master cylinder cap 1 2 Diaphragm 1 3 Reservoir float 1 4 Push rod (Front) 1 5 Brake master cylinder boot 1 6 Circlip 1 7 Washer 1 8 Push rod (Rear) 1 9 Brake master cylinder kit 1 5-9 Front Rear Use a long nose circlip pliers.
FRONT BRAKE AND REAR BRAKE HANDLING NOTE Support the machine securely so there is no danger of it falling over. DRAINING THE BRAKE FLUID 1. Remove: • Brake master cylinder cap "1" • Protector (rear brake) Do not remove the diaphragm. • Cover piston with rag and use extreme caution when expelling piston from cylinder. • Never attempt to pry out piston. Caliper piston removal steps: a. Insert a piece of rag into the brake caliper to lock one brake caliper. b.
FRONT BRAKE AND REAR BRAKE • Replace the brake caliper piston seals and brake caliper piston dust seals whenever a caliper is disassembled. CHECKING THE BRAKE CALIPER 1. Inspect: • Brake caliper cylinder inner surface "a" Wear/score marks → Replace brake caliper assembly. INSTALLING THE BRAKE CALIPER PISTON 1. Clean: • Brake caliper • Brake caliper piston seal • Brake caliper piston dust seal • Brake caliper piston Clean them with brake fluid. 2.
FRONT BRAKE AND REAR BRAKE 4. • • • • • • INSTALLING THE REAR BRAKE CALIPER 1. Install: • Pad support "1" • Brake pad "2" • Pad pin "3" • Install the brake pads with their projections "a" into the brake caliper recesses "b". • Temporarily tighten the pad pin at this point. INSTALLING THE BRAKE MASTER CYLINDER KIT 1. Clean: • Brake master cylinder • Brake master cylinder kit Clean them with brake fluid. 2.
FRONT BRAKE AND REAR BRAKE 2. Install: • Brake lever "1" • Bolt (brake lever) "2" 2. Install: • Brake master cylinder "1" • Bolt (brake master cylinder) "2" Bolt (brake lever): 6 Nm (0.6 m•kg, 4.3 ft•lb) Bolt (brake master cylinder): 10 Nm (1.0 m•kg, 7.2 ft•lb) • Nut (brake lever) "3" Union bolt: 30 Nm (3.0 m•kg, 22 ft•lb) Always use new copper washers. Nut (brake lever): 6 Nm (0.6 m•kg, 4.3 ft•lb) Apply the silicone grease on the brake lever sliding surface, bolt and tip of the push rod. 3.
FRONT BRAKE AND REAR BRAKE 4. • • • Install: Copper washer "1" Brake hose "2" Union bolt "3" Union bolt: 30 Nm (3.0 m•kg, 22 ft•lb) Always use new copper washers. 2. Install: • Brake hose holder "1" • Screw (brake hose holder) "2" Screw (brake hose holder): 3 Nm (0.3 m•kg, 2.2 ft•lb) Install the brake hose so that its pipe portion "a" directs as shown and lightly touches the projection "b" on the brake master cylinder. INSTALLING THE REAR BRAKE HOSE 1.
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 master 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 there is any brake fluid leaking where the union bolts are installed respectively at the brake master cylinder and brake caliper. A. Front B. Rear 5.
FRONT FORK FRONT FORK REMOVING THE FRONT FORK Order Part name Q'ty Remarks Hold the machine by placing the suitable stand under the engine. Refer to "HANDLING NOTE". Front wheel Refer to "FRONT WHEEL AND REAR WHEEL" section. Front brake caliper Refer to "FRONT BRAKE AND REAR BRAKE" section. Number plate Refer to "SEAT, FUEL TANK AND SIDE COVERS" section in the CHAPTER 4. 1 Protector 1 2 Pinch bolt (upper bracket) 2 Only loosening.
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 1 Adjuster 1 2 Fork spring 1 Remarks Drain the fork oil. Refer to removal section. 3 Dust seal 1 Refer to removal section. 4 Stopper ring 1 Refer to removal section. 5 Inner tube 1 Refer to removal section.
FRONT FORK HANDLING NOTE Support the machine securely so there is no danger of it falling over. The front fork requires careful attention. So it is recommended that the front fork be maintained at the dealers. To prevent an accidental explosion of air, the following instructions should be observed: • The front fork with a built-in piston rod has a very sophisticated internal construction and is particularly sensitive to foreign material.
FRONT FORK CHECKING THE BASE VALVE 1. Inspect: • Base valve "1" Wear/damage → Replace. Contamination → Clean. • O-ring "2" Wear/damage → Replace. • Piston metal "3" Wear/damage → Replace. • Spring "4" Damage/fatigue → Replace base valve. • Air bleed screw "5" Wear/damage → Replace. CHECKING THE COLLAR 1. Inspect: • Piston metal "1" Wear/damage → Replace. CHECKING THE FORK SPRING 1. Measure: • Fork spring free length "a" Out of specification → Replace. Fork spring free length "a": 454 mm (17.
FRONT FORK 6. Tighten: • Locknut "1" Fully finger tighten the locknut onto the damper assembly. Hold the damper assembly with the cap bolt ring wrench "2" and use the cap bolt wrench "3" to tighten the base valve with specified torque. 14. Check: • Damper assembly smooth movement Tightness/binding/rough spots → Repeat the steps 2 to 13. Cap bolt wrench: YM-01500/90890-01500 Cap bolt ring wrench: YM-01501/90890-01501 7.
FRONT FORK 17. Install: • Outer tube "1" To inner tube "2". 21. Install: • Dust seal "1" 18. Install: • Slide metal "1" • Oil seal washer "2" To outer tube slot. Apply the lithium soap base grease on the inner tube. Press the slide metal into the outer tube with fork seal driver "3". 25. Install: • Damper assembly "1" To inner tube "2". To install the damper assembly into the inner tube, hold the inner tube aslant.
FRONT FORK 31. Fill: • Front fork oil "1" From outer tube top. 28. Inspect: • Gap "a" between the adjuster "1" and locknut "2". Out of specification → Retighten and readjust the locknut. Gap "a" between the adjuster and locknut: 0.5–1.0 mm (0.02–0.04 in) If the adjuster is installed out of specification, proper damping force cannot be obtained. 29. Tighten: • Adjuster (locknut) "1" Adjuster (locknut): 29 Nm (2.9 m•kg, 21 ft•lb) Recommended oil: Suspension oil "S1" Standard oil amount: 333 cm3 (11.
FRONT FORK 4. Tighten: • Pinch bolt (upper bracket) "1" Pinch bolt (upper bracket): 21 Nm (2.1 m•kg, 15 ft•lb) 7. Adjust: • Compression damping force Turn in the damping adjuster "1" finger-tight and then turn out to the originally set position. • Pinch bolt (lower bracket) "2" Pinch bolt (lower bracket): 21 Nm (2.1 m•kg, 15 ft•lb) Tighten the lower bracket to specified torque. If torqued too much, it may cause the front fork to malfunction. 5.
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) Order Part name Q'ty Number plate Remarks Remove the band only. 1 Clutch cable 1 2 Clutch lever holder 1 3 Engine stop switch 1 4 Brake master cylinder 1 Refer to removal section.
HANDLEBAR DISASSEMBLING THE THROTTLE Order Part name Q'ty 1 Grip cap (lower) 1 2 Grip cap (upper) 1 3 Grip assembly 1 4 Grip (right) 1 5 Tube guide 1 5-25 Remarks Refer to removal section.
HANDLEBAR REMOVING THE BRAKE MASTER CYLINDER 1. Remove: • Brake master cylinder bracket "1" • Brake master cylinder "2" • Do not let the brake master cylinder hang on the brake hose. • Keep the brake master cylinder cap side horizontal to prevent air from coming in. • Before applying the adhesive, wipe off grease or oil on the tube guide surface "a" with a lacquer thinner. • Align the mating mark "b" on the grip (right) with the slot "c" in the tube guide. 2. • • • REMOVING THE GRIP 1.
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. 3. Tighten: • Nut (handlebar lower holder) "1" Nut (handlebar lower holder): 40 Nm (4.0 m•kg, 29 ft•lb) Bolt (brake master cylinder bracket): 9 Nm (0.9 m•kg, 6.5 ft•lb) 7.
HANDLEBAR After tightening the bolts, check that the throttle grip "2" moves smoothly. If it does not, retighten the bolts for adjustment. 15. Adjust: • Clutch lever free play Refer to "ADJUSTING THE CLUTCH LEVER FREE PLAY" section in the CHAPTER 3. 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.
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 under the engine. Refer to "HANDLING NOTE". Number plate Refer to "SEAT, FUEL TANK AND SIDE COVERS" section in the CHAPTER 4. Handlebar Refer to "HANDLEBAR" section.
STEERING Order 9 Part name Q'ty Bearing race 2 5-30 Remarks Refer to removal section.
STEERING HANDLING NOTE Support the machine securely so there is no danger of it falling over. CHECKING THE STEERING STEM 1. Inspect: • Steering stem "1" Bend/damage → Replace. REMOVING THE STEERING RING NUT 1. Remove: • Steering ring nut "1" Use the steering nut wrench "2". Steering nut wrench: YU-33975/90890-01403 Support the steering stem so that it may not fall down. REMOVING THE LOWER BEARING 1. Remove: • Lower bearing "1" Use the floor chisel "2". 3.
STEERING 6. Install: • Washer "1" 11. Tighten: • Pinch bolt (upper bracket) "1" Pinch bolt (upper bracket): 21 Nm (2.1 m•kg, 15 ft•lb) • Pinch bolt (lower bracket) "2" 7. Install: • Front fork "1" • Upper bracket "2" • Temporarily tighten the pinch bolts (lower bracket). • Do not tighten the pinch bolts (upper bracket) yet. Pinch bolt (lower bracket): 21 Nm (2.1 m•kg, 15 ft•lb) Tighten the lower bracket to specified torque. If torqued too much, it may cause the front fork to malfunction. 8.
SWINGARM SWINGARM REMOVING THE SWINGARM Order Part name Q'ty Remarks Hold the machine by placing the suitable stand under the engine. Refer to "HANDLING NOTE". Brake hose holder Refer to "FRONT BRAKE AND REAR BRAKE" section. Rear brake caliper Refer to "FRONT BRAKE AND REAR BRAKE" section. Bolt (brake pedal) Shift the brake pedal backward.
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 1 Cap 2 2 Relay arm 1 3 Connecting rod 1 4 Collar 2 5 Oil seal 2 6 Thrust bearing 2 7 Bushing 2 8 Oil seal 8 9 Bearing 10 5-34 Remarks Refer to removal section. Refer to removal section.
SWINGARM HANDLING NOTE Support the machine securely so there is no danger of it falling over. 2. Inspect: • Oil seal "3" Damage → Replace. REMOVING THE CAP 1. Remove: • Left cap "1" Remove with a slotted-head screwdriver inserted under the mark "a" on the left cap. REMOVING THE BEARING 1. Remove: • Bearing "1" CHECKING THE CONNECTING ROD 1. Inspect: • Bearing "1" • Collar "2" Free play exists/unsmooth revolution/rust → Replace bearing and collar as a set. 2. Inspect: • Oil seal "3" Damage → Replace. 2.
SWINGARM 4. • • • • INSTALLING THE SWINGARM 1. Install: • Bushing "1" • Thrust bearing "2" • Oil seal "3" • Collar "4" To swingarm "5". Install: Connecting rod "1" Bolt (connecting rod) "2" Washer "3" Nut (connecting rod) "4" Nut (connecting rod): 80 Nm (8.0 m•kg, 58 ft•lb) To relay arm "5". Apply the molybdenum disulfide grease on the bolt. Apply the molybdenum disulfide grease on the bushings, thrust bearings, oil seal lips and contact surfaces of the collar and thrust bearing. 8. • • • 5.
SWINGARM 10. Tighten: • Nut (connecting rod) "1" Nut (connecting rod): 80 Nm (8.0 m•kg, 58 ft•lb) 14. Install: • Drive chain support "1" • Drive chain support cover "2" • Bolt {drive chain support [L = 50 mm (1.97 in)]} "3" • Nut (drive chain support) "4" Nut (drive chain support): 7 Nm (0.7 m•kg, 5.1 ft•lb) • Bolt {drive chain support cover [L = 10 mm (0.39 in)]} "5" 11. Tighten: • Nut (relay arm) "1" Nut (relay arm): 70 Nm (7.0 m•kg, 50 ft•lb) Bolt (drive chain support cover): 7 Nm (0.7 m•kg, 5.
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 Q'ty Remarks Hold the machine by placing the suitable stand under the engine. Refer to "HANDLING NOTE". Seat Refer to "SEAT, FUEL TANK AND SIDE COVERS" section in the CHAPTER 4. Silencer Refer to "EXHAUST PIPE AND SILENCER" section in the CHAPTER 4.
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 12 Part name Q'ty Bearing 2 5-39 Remarks Refer to removal section.
REAR SHOCK ABSORBER HANDLING NOTE • Support the machine securely so there is no danger of it falling over. • This rear shock absorber is provided with a separate type tank filled with high-pressure nitrogen gas. To prevent the danger of explosion, read and understand the following information before handling the shock absorber. The manufacturer can not be held responsible for property damage or personal injury that may result from improper handling.
REAR SHOCK ABSORBER 2. Install: • Stopper ring (upper bearing) "1" 3. Tighten: • Adjuster "1" After installing the stopper ring, push back the bearing until it contacts the stopper ring. 3. Install: • Lower bearing "1" 4. Adjust: • Spring length (installed) Refer to "ADJUSTING THE REAR SHOCK ABSORBER SPRING PRELOAD" section in the CHAPTER 3. 5. Tighten: • Locknut "1" Install the bearing by pressing it on the side having the manufacture's marks or numbers. Installed depth of the bearing "a": 4 mm (0.
REAR SHOCK ABSORBER 6. Install: • Rear frame "1" • Bolt [rear frame (upper)] "2" Bolt [rear frame (upper)]: 32 Nm (3.2 m•kg, 23 ft•lb) • Bolt [rear frame (lower)] "3" Bolt [rear frame (lower)]: 29 Nm (2.9 m•kg, 21 ft•lb) 7. Tighten: • Bolt (air filter joint) "1" Bolt (air filter joint): 2 Nm (0.2 m•kg, 1.
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 requested not to undertake inspection, adjustment, disassembly, or reassembly only by reference to this manual. It may lead to servicing trouble and mechanical damage.
ELECTRICAL COMPONENTS AND WIRING DIAGRAM ELECTRICAL COMPONENTS AND WIRING DIAGRAM ELECTRICAL COMPONENTS 1. 2. Engine stop switch CDI unit 3. 4. Ignition coil CDI magneto WIRING DIAGRAM 1. 2. 3. 4. 5. Engine stop switch CDI unit Ignition coil CDI magneto Spark plug COLOR CODE B Black O Orange Y Yellow B/R Black/Red B/W Black/White G/L Green/Blue G/W Green/White W/L White/Blue W/R White/Red 6-2 5.
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 ↓ Check entire ignition system for connection. No good → Repair or replace. No good → Replace. OK ↓ Check engine stop switch. OK ↓ Check ignition coil. (primary coil and secondary coil) No good → Replace.
IGNITION SYSTEM SPARK GAP TEST 1. Disconnect the spark plug cap from spark plug. 2. Connect the dynamic spark tester "1" (ignition checker "2") as shown. • Ignition coil "3" • Spark plug "4" CHECKING THE ENGINE STOP SWITCH 1. Inspect: • Engine stop switch conduction Tester (+) lead→Black/White lead "1" Tester (-) lead → Black lead "2" Result Conductive (while the engine stop switch is pushed) Secondary coil resistance Tester selector position 5.7–8.
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" Pickup coil resistance Tester selector position 248–372 Ω at 20 °C (68 °F) Ω × 100 2. Inspect: • Charging coil 1 resistance Out of specification → Replace. 3. Inspect: • Charging coil 2 resistance Out of specification → Replace.
ENGINE TUNING ENGINE CARBURETOR SETTING • The role of fuel is to cool the engine, and in the case of a 2-stroke engine, to lubricate the engine in addition to power generation. Accordingly, if a mixture of air and fuel is too lean, abnormal combustion will occur, and engine seizure may result. If the mixture is too rich, spark plugs will get wet with oil, thus making it impossible to bring the engine into full play or if the worst comes to the worst, the engine may stall.
ENGINE ADJUSTING THE PILOT JET The richness of air-fuel mixture with the throttle fully closed to 1/2 open can be set by changing the pilot jet "1". It is changed when adjustment cannot be made by the pilot air screw alone. #40 Standard pilot jet *#45 *Except for USA and CDN ADJUSTING THE JET NEEDLE On the carburetors used in the YZ125, the main nozzle is a non disassembly type, so it can not be replaced. Therefore, carburetor setting requires the change of the jet needle. 1.
ENGINE CARBURETOR SETTING PARTS Main jet "1" Size Part number (-14143-) Jet needle "4" Size Part number (-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 #420 137-84 Rich 6BFY43-72 284-J2 #410 137-82 6BFY43-73 284-J3 Lean #400 137-80 (STD) 6BFY43-74 284-J4 Pilot jet "2" Rich ** (STD) * (STD) Lean Size Part number (-14142-) 6BFY43-75 284-J5
ENGINE ROAD CONDITION AND EXAMPLES OF CARBURETOR SETTING General condition 15–25°C (59–77°F) Over 30°C (86°F) Under 10°C (50°F) 15–25°C (59–77°F) Over 30°C (86°F) (Winter) (Spring, Autumn) (Summer) (Winter) (Spring, Autumn) (Summer) #440 #430 #420 #460 #450 #440 6BFY44-74-3 6BFY43-74-3 6BFY44-74-2 6BFY43-74-4 6BFY44-74-3 6BFY43-74-3 A #42.5 #40 #40 #42.5 #40 #40 B #47.5 #45 #42.5 #47.5 #45 #42.
ENGINE Symptom Lean mixture Rich mixture 1/4–3/4 throttle *Hard breathing Lack of speed Setting Checking Lower jet needle clip position. (1 groove down) Groove 1 Groove 2 Raise jet needle clip position. (1 groove up) Groove 3 Groove 4 Lower jet needle clip position. (1 groove Groove 5 down) 1/4–1/2 throttle Slow speed pick-up White smoke Poor acceleration Raise jet needle clip position. (1 groove up) 0–1/4 throttle *Hard breathing Speed down Use jet needle having a smaller diameter.
CHASSIS CHANGE OF THE HEAT RANGE OF SPARK PLUGS Judging from the discoloration of spark plugs, if they are found improper, it can be corrected by the following two methods; changing carburetor settings and changing the heat range of spark plug. Standard spark plug BR9EVX/NGK (resistance type) • In principle, it is advisable to first use spark plugs of standard heat range, and judging from the discoloration of spark plugs, adjust carburetor settings. • If the calibration No.
CHASSIS Adjust the oil amount in 5 cm 3 (0.2 Imp oz, 0.2 US oz) increments or decrements. Too small oil amount causes the front fork to produce a noise at full rebound or the rider to feel some pressure on his hands or body. Alternatively, too large oil amount will cause the air spring characteristics to have a tendency to be stiffer with the consequent deteriorated performance and characteristics. Therefore, adjust the front fork within the specified range. Standard oil amount: 333 cm3 (11.72 Imp oz, 11.
CHASSIS set length, replace the spring with an optional one and make readjustment. REAR SHOCK ABSORBER SETTING PARTS • Rear shock spring "1" [Equal-pitch titanium spring] TYPE SPRI NG RATE SPRING PART NUMBER (-22212-) Install the spring seat "2" to the titanium spring. I.D. MARK Green/1 SETTING OF SPRING AFTER REPLACEMENT After replacement, be sure to adjust the spring to the set length [sunken length 90–100 mm (3.5–3.9 in)] and set it. 1.
CHASSIS • Extent of adjustment (spring preload) SPRING PART NUMBER (-22212-) 1C3-00 1C3-10 1C3-20 1C3-30 5UN-00 5UN-A0 5UN-B0 5UN-C0 5UN-D0 5UN-E0 5UN-F0 5UN-G0 5UN-50 5UN-60 5UN-70 Maximum Minimum Position in which the spring is turned in 18 mm Position (0.71 in) in which from its the spring free is turned length. in 1.5 mm (0.06 in) from its Position free in which length. the spring is turned in 20 mm (0.79 in) from its free length.
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).
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. • Adjust the low compression damping in 1-click increments or decrements. • Adjust the high compression damping in 1/6 turn increments or decrements.
PRINTED ON RECYCLED PAPER PRINTED IN JAPAN (E)
