background image

SERVICE MANUAL

DT125RE

1D01-AE1

DT125X

2005

Summary of Contents for DT125RE 2005

Page 1: ...SERVICE MANUAL DT125RE1D01 AE1 DT125X 2005 ...

Page 2: ...RVICE MANUAL 2005 Yamaha Motor España S A 1st Edition January 2005 All rights reserved Any reprinting or unauthorized use without the written permission of Yamaha Motor España S A is expressly prohibited Printed in Spain EAS00001 ...

Page 3: ...cant changes in specifications or procedures will be forwarded to all authorized Yamaha dealers and will appear in future editions of this manual where applicable NOTE Designs and specifications are subject to change without notice TECHNICAL PUBLICATIONS YAMAHA MOTOR ESPAÑA S A EAS00004 IMPORTANT MANUAL INFORMATION Particularly important information is distinguished in this manual by the following...

Page 4: ...top of each page except in Chapter 3 PERIODIC CHECKS AND ADJUSTMENTS where the sub section title s appears Sub section titles appear in smaller print than the section title To help identify parts and clarify procedure steps there are exploded diagrams at the start of each removal and disassembly section Numbers are given in the order of the jobs in the exploded diagram A circled number indi cates ...

Page 5: ...bricant 13 Special tool 14 Tightening torque 15 Wear limit clearance 16 Engine speed 17 Electrical data Symbols 18 to 23 in the exploded diagrams indicate the types of lubricants and lubrica tion points 18 Engine oil 19 Gear oil 20 Molybdenum disulfide oil 21 Wheel bearing grease 22 Lithium soap based grease 23 Molybdenum disulfide grease Symbols 24 to 25 in the exploded diagrams indicate the foll...

Page 6: ...S CHK ADJ 3 PERIODIC CHECKS AND ADJUSTMENTS CHAS 4 CHASSIS ENG 5 ENGINE COOL 6 COOLING SYSTEM CARB 7 CARBURETOR ELEC 8 ELECTRICAL SYSTEM EAS00010 TABLE OF CONTENTS TRBL SHTG 9 TROUBLESHOOTING GENERAL INFORMATION GEN INFO 1 ...

Page 7: ...GEN INFO ...

Page 8: ...1 ...

Page 9: ...IAL NUMBER 1 1 ENGINE SERIAL NUMBER 1 1 IMPORTANT INFORMATION 1 2 PREPARATION FOR REMOVAL 1 2 ALL REPLACEMENT PARTS 1 2 GASKETS OIL SEALS AND O RINGS 1 2 LOCK WASHERS PLATES AND COTTER PINS 1 2 BEARINGS AND OIL SEALS 1 3 CIRCLIP 1 3 CHECKING THE CONNECTIONS 1 4 SPECIAL TOOLS 1 5 ...

Page 10: ... number is used to identify the motorcycle and therefore it can be used for the enrollment in the face of the competent autho rity ENGINE SERIAL NUMBER The engine serial number is stamped onto the left side of the crankcase NOTE The first three digits of this number identifies the model the other digits indicate the num ber of production of the unit NOTE Design and specifications may change withou...

Page 11: ...ll of the parts and place them in trays in the order of disassembly This will speed up assembly and allow for the correct installation of all parts 5 Keep all parts away from any source of fire EAS00021 REPLACEMENT PARTS Use only genuine Yamaha parts for all replace ments Use oil and grease recommended by Yamaha for all lubrication jobs Other brands may be similar in function and appearance but in...

Page 12: ...ease Oil bearings liberally when installing if appro priate Oil seal CAUTION Do not spin the bearing with compressed air because this will damage the bearing surfaces Bearing EAS00025 CIRCLIPS Before reassembly check all circlips carefully and replace damaged or distorted circlips Always replace piston pin clips after one use When installing a circlip make sure the sharp edged corner is positioned...

Page 13: ...disconnect several times 3 Check all connections Loose connection Connect properly NOTE If the pin on the terminal is flattened bend it up 4 Connect lead coupler connector NOTE Make sure all connections are tight 5 Check continuity with the pocket tester NOTE If there is no continuity clean the terminals When checking the wire harness perform steps 1 to 3 As a quick remedy use a contact revitalize...

Page 14: ...ustration 90890 01312 Fuel level gauge This gauge is used to measure the fuel level in the float chamber 90890 03113 Engine tachometer This tool is needed for detecting engine rpm 90890 04086 Universal tool of subjection of the clutch This tool is used to immobilize the clutch during the assembly or disassembly of the blockade nut of the clutch 90890 01701 Sheave holder This tool is used for holdi...

Page 15: ...8 3 Adapter M12 90890 01326 T Handle This tool is used for holding the damper rod holder when removing or installing the damper rod holder 90890 01367 Fork seal driver weight 01381 Fork seal driver attachment This tool is used when installing the fork seal 90890 01403 Ring nut wrench This tool is used to loosen and tighten the steering ring nut 90890 03112 Pocket tester These instruments are inval...

Page 16: ......

Page 17: ...SPEC ...

Page 18: ...2 ...

Page 19: ...CATIONS 2 4 CHASSIS SPECIFICATIONS 2 6 ELECTRICAL SPECIFICATIONS 2 8 CONVERSION TABLE 2 10 GENERAL TIGHTENING TORQUE SPECIFICATIONS 2 10 ENGINE 2 11 CHASSIS 2 11 COOLANT FLOW CHART 2 13 LUBRICATION POINTS AND LUBRICANT TYPE 2 14 ENGINE 2 14 CHASSIS 2 15 CABLE ROUTING 2 16 ...

Page 20: ...ement Forward inclined single cylinder Displacement 124cm3 BorexStroke 56 0x50 7 Compression ratio 6 7 1 Maximum power 11kW 8000rpm Maximum torque 13Nm 8000rpm Idle speed 1250 1450r min Starting system Electric starter Lubrication system Yamaha Autolube Oil type or grade Engine oil 2T motor oil JASO grade FC Total amount 1 3L Transmission oil Type SE motor oil Periodic oil change 0 75L 0 79 us qt ...

Page 21: ...t 80 90 21 48P 120 70 17 58H Rear 110 80 18 58P 140 70 17 66H Manufacturer Michelin T63 Pirelli Sport Demon Cold tire pressure Front 0 90kg 150kPa 1 5kgf cm2 180kPa 1 8kgf cm2 Rear 0 90kg 175kPa 1 75kgf cm2 200kPa 2 0kgf cm2 Front 90 178kg 175kPa 1 75kgf cm2 180kPa 1 8kgf cm2 Rear 90 178kg 200kPa 2 0kgf cm2 200kPa 2 0kgf cm2 Off road riding Front 150kPa 1 5kgf cm2 Rear 175kPa 1 75kgf cm2 Brakes Fr...

Page 22: ...ion system CDI Charging system AC Magneto Battery type GT6B 3 Capacity 12V 6Ah Headlight bulb type Bulb wattage x quantity Headlight 12V60W 55W x 1 Tail Brake light 12V21W 5W x 1 Turn signal indicator light Front 12V10W x 1 Rear 12V10W x 1 Meter LED Control lights OIL 12V3W X 1 TURN 12V3W X 1 NEUTRAL 12V3W X 1 HIGH BEAM 12V3W X 1 LOW BEAM 12V3W X 1 Amperages Principal fuse 15A ...

Page 23: ... 10mm Piston Offset 0 5mm Piston ring Type Keystone Dimensions BxT Top ring 1 2x2 4mm 2nd ring 1 20x1 89mm End gap installed Top ring 0 30 0 45mm 2nd ring 0 30 0 45mm Side clearance Top ring 0 02 0 06mm 2nd ring 0 035 0 070mm Cooling system Radiator capacity including all routes 0 92L Reservoir tank capacity 0 3L Radiator cap opening pressure 75 105kPa 0 75 1 05kgf cm2 Radiator core width 110mm Ra...

Page 24: ...it 0 08mm Carburetor Type TM28 92 1 ID Mark 1DO Main jet 210 Air jet 0 7 Jet Needle position 5J40 2 Needle jet Q2M 939 Pilot outlet 0 6 Pilot jet 17 5 Bypass1 1 6 Air screw turns 1 4 Valve seat size 2 8 Starter jet 1 40 Power jet 60 Float height 15 5 16 5mm Fuel level 1 5 2 5mm Idling speed 1250 1450r p m Air filter Type Wet element Oil type grade Foam air filter oil or SAE10W30SE Reed valve Valve...

Page 25: ...inner 6mm 4 1mm 0 8mm 0 5mm Brake pad lining thickness outer 6 mm 6 mm 0 8mm 0 8mm Master cylinder inside diameter 11mm 11mm Caliper cylinder inside diameter 34 93mm 34 93mm Recommended fluid DOT 4 DOT 4 Rear disc brake Thickness 220 0x4 5mm Brake pad lining thickness inner 5 6mm 1 0mm Brake pad lining thickness outer 5 6mm 1 0mm Master cylinder inside diameter 12 7mm Caliper cylinder inside diame...

Page 26: ...ght Hard Soft Hard Soft 220 235mm 234 249mm Spring rate K1 68 6N mm 117 80N mm Spring stroke K1 0 93mm 0 87mm Optional spring available No No Enclosed gas air pressure STD 150kPa 150kPa 15kgf cm2 15kgf cm2 Tightening torque spring preload 20 25Nm 20 25Nm Drive chain Type Manufacturer 428V2 DAIDO 428V2 DAIDO Link quantity 134 134 Drive chain slack 45 55mm 25 40mm 1 77 2 16in 0 98 1 57in Front lever...

Page 27: ... 20 Secondary coil resistance ohm 7 9 20 Spark plug cap Material Resin Resistance k ohm 5 A C Magneto Model Manufacturer F4FU YAMAHA Standard output 14V170W5000r min Coil resistance ohm 0 6 20 W W Regulator Regulator type Semi conductor short circuit Model Manufacturer SH629B 11 SHINDENGEN No load regulated voltage 14 1 14 9V Rectifier Rectifier capacity 25A Withstand voltage 200V Battery Battery ...

Page 28: ...JIDECO Amperage 180A Coil resistance 4 2 4 6 ohm 20ºC Horn Horn type Plane Quantity 1 Model Manufacturer YF 12 NIKKO Max Amperage 3A Performance 105 113db 2m Turn signal relay Relay type Full transistor Model Manufacturer FE218BH DENSO Turn signal blinking frequency 75 95cyl min Wattage 10Wx2 3 4W Oil level gauge Model Manufacturer 3XP ASTI Starting citcuit cutt off relay Model Manufacturer 25G OM...

Page 29: ... 8799 qt IMP liq lt liter 0 2199 gal IMP liq kg mm 55 997 lb in Misc kg cm2 14 2234 psi lb in2 Centigrade 9 5 32 Fahrenheit F C EAS00029 GENERAL TIGHTENING TORQUE SPECIFICATIONS This chart specifies tightening torques for standard fasteners with a standard ISO thread pitch Tightening torque specifications for special components or assemblies are provi ded for each chapter of this manual To avoid w...

Page 30: ...mp Screw 2 M5x0 8 5 0 5 Carburetor joint Bolt 4 M6x1 0 8 0 8 Air filter Screw 2 M6x1 0 5 0 5 Exhaust pipe Nut 2 M8x1 25 18 1 8 Stud bolt 2 M8x1 25 10 1 LOCTITE screw glue Bolt 3 M6x1 0 8 0 8 Transmission Oil Drain Bolt 1 M8x1 25 15 1 5 Crankcase cover left Screw 6 M6x1 0 5 0 5 Crankcase cover right Screw 6 M6x1 0 8 0 8 Oil pump cover Screw 3 M6x1 0 5 0 5 Crankcase Screw 12 M6x1 0 8 0 8 Oil Seal Ho...

Page 31: ...inder to holder M6 7 5 12 0 75 1 2 Brake pipe bolt M10 23 37 2 3 3 7 Security pin rear brake lever to pump Completely bend Pivot shaft M15 80 100 8 0 10 0 Swingarm to connecting arm M13 45 70 4 5 7 0 Connecting arm relay arm M13 45 70 4 5 7 0 Relay arm to frame M13 45 70 4 5 7 0 Damper to frame M10 30 35 3 0 3 5 Damper to relay arm M10 30 35 3 0 3 5 Swingarm end bolts 2 4 0 2 0 4 Driven sprocket M...

Page 32: ...13 COOLANT FLOW CHART Water pump Crankcase cover Crankcase Cylinder Cylinder head Bypass hose Thermostatic valve Thermostatic valve Outlet hose Radiator Inlet hose Coolant cold Less than 65 C 149 F Coolant hot 165 149 F or more ...

Page 33: ...ver bearings Apply gear oil Crank pins Apply engine oil Piston rings piston pins and pistons Apply engine oil Power valve holder Apply lightweight lithium soap base grease Impeller shaft water pump Apply gear oil Warm shaft Autolube pump Apply engine oil Kick idle gear Apply gear oil Kick axle Apply gear oil Primary driven gear clutch housing Apply gear oil Push rod Apply gear oil Push lever axle ...

Page 34: ...ts free play Apply lightweight lithium soap base grease Rear footrests free play ball and axle Apply lightweight lithium soap base grease Swingarm axle to frame Apply lightweight lithium soap base grease Relay arm to swingarm Apply lightweight lithium soap base grease Connecting rods Apply lightweight lithium soap base grease Engine holder to cylinder head Apply lightweight lithium soap base greas...

Page 35: ...ead Left turn signal lead Throttle cable Indicator light wire lead Meter wire lead Headlight bulb wire Handle wire lead right A Cover with cap after connecting wires B Route the installation between lower brac ket and headlight bottom holder C Clamp connection wire A B C ...

Page 36: ...side after route the throttle wire C Clamp handle wire lead L D Clamp handle wire lead R E Clamp pipe overflow to the frame clamp F Hold hoses on chassis clamp G Cover with cap after connecting wires H Route brake tail light wire through rear mudguard hole I Clamp rear turning light wire R and tail brake lights wire to frame clamp J Route the following cables through the frame bracket rear turning...

Page 37: ... Oil pipe A Route speedometer cable to frame guide B Route pipe overflow behind engine holder C Screw ground wire and rectifier with the same bolt D Pipe overflow pass behind oil hose E Route carburetor breather hose between rear shock absorber and swingarm F Route pipe overflow between rear shock absorber and swingarm C A B D E F ...

Page 38: ...sert installation clip to frame hole E Route clutch wire through the guides F Connect ground on the front part of the coil Install screw and wire terminal G Cover thermo switch with cap H Insert connector to frame clamp X3 I Install clamp with open part to the upper side Route pipe overflow and pipe I through clamp J Route sidestand switch through brackets The lead must have no slack at distance X...

Page 39: ...CHK ADJ ...

Page 40: ...3 ...

Page 41: ...NSPECTION 3 18 CHECKING THE CRANKCASE BREATHER HOSE 3 18 EXHAUST SYSTEM INSPECTION 3 19 ENGINE OIL LINE INSPECTION 3 19 COOLANT LEVEL INSPECTION 3 19 COOLANT REPLACEMENT 3 20 COOLING SYSTEM INSPECTION 3 23 CHASSIS 3 24 FRONT BRAKE ADJUSTMENT 3 24 REAR BRAKE ADJUSTMENT 3 24 BRAKE FLUID INSPECTION 3 25 BRAKE PAD INSPECTION 3 27 BRAKE LIGHT SWITCH ADJUSTMENT 3 27 BRAKE HOSE INSPECTION 3 28 DRIVE CHAI...

Page 42: ...s or damage bearings 11 Swingarm Check operation and for excessive play Lubricate with lithium soap based grease Every 24 000 km 12 Drive chain Check chain slack Make sure that the rear wheel is properly aligned Every 500 km and after washing Clean and lubricate the motorcycle or riding in the rain 13 Steering Check bearing play and steering for roughness bearings Lubricate with lithium soap based...

Page 43: ...sen both locknuts and turn in both adjusters Insert a pin fl 0 16 in through the aligning indent in the pulley and into the hole to lock the pulley Turn both adjusters counterclockwise so that the cable free play becomes zero mm zero in with fingers Turn both adjusters 1 4 turn clockwise Tighten the locknuts Turn on the main switch and check taht the alignment mark is aligned If not rpeat the abov...

Page 44: ...cification Adjust 4 Adjust engine idling speed a Turn the pilot screw in or out until it is lightly seated b Turn the pilot screw out the specified num ber of turns c Turn the throttle stop screw in direction a or b until the specified engine idling speed is obtained 5 Adjust throttle cable free play Refer to ADJUSTING THE THROTTLE CABLE FREE PLAY Engine tachometer 90890 03113 Engine idling speed ...

Page 45: ...y Handlebar side a Loosen the locknut b Turn the adjusting nut in direction a or b until the specified throttle cable free play is obtained c Tighten the locknut s s WARNING After adjusting the throttle cable free play start the engine and turn the handlebar to the right or left to ensure that this does not cause the engine idling speed to change Throttle cable free play at the flange of the throt...

Page 46: ... be adjusted 1 Pull back the adjuster cover 2 Check carburetor cable free play a Out of specification adjust 3 Adjust Caburetor free play Adjustment steps Loosen the locknut Turn the adjuster in or out until the correct free play obtained Tighten the locknuts 4 Push in the adjuster cover Carburetor Cable Free Play 1 0 mm 0 04 in Turn in Free play is increased Turn out Free play is decreased 2 3 ...

Page 47: ...y ends Adjustment steps a Loosen the locknut b Turn the adjuster until the correct adjust ment is obtained c Tighten the locknut AUTOLUBE PUMP AIR BLEEDING NOTE The Autolube pump and delivery lines must be bleed on the following ocasions Setting up a new motorcycle out of the crate Whenever the oil tank has run dry Whenever any portion of the engine oil sys tem is disconnected 1 Remove autolube pu...

Page 48: ...l pan under the autolube pump to catch the oil EAS00060 CHECKING THE SPARK PLUG 1 Disconnect spark plug cap 2 Remove spark plug CAUTION Before removing the spark plug blow away any dirt accumulated in the spark plug well with compressed air to prevent it from falling into the cylinder 3 Check spark plug type Incorrect Change 4 Check electrode Damage wear Replace the spark plug insulator Abnormal c...

Page 49: ...ct spark plug cap EAS00064 CHECKING THE IGNITION TIMING NOTE Prior to checking the ignition timing check the wiring connections of the entire ignition sys tem Make sure all connections are tight and free of corrosion 1 Remove crankcase cover left 2 Connect timing light engine tachometer onto the spark plug lead of cylinder 1 Spark plug gap 0 7 0 8mm 0 0276 0 03315in Spark plug 20Nm 2 0m kg 14ft lb...

Page 50: ...k that the stationary pointer is within the firing range on the generator rotor Incorrect firing range Check the ignition system NOTE The ignition timing is not adjustable 4 Install Crankcase cover left ENGINE OIL LEVEL INSPECTION 1 Check oil level oil level low Adjust sufficient oil Engine idling speed 1250 1450 r min Recommended oil Yamaha Oil 2T or Air Cooled 2 stroke Engine Oil Oil Tank Capaci...

Page 51: ...ction and lead to poor performance OIL Indicator light OIL WARNING LIGHT CHECKING METHOD Main Switch ON Gears in NEUTRAL Oil warning indicator light does not come on Refeer to CHAPTER 8 SIGNAL SYSTEM Oil warning indicator light come on Shift into gear Oil warning indicator light does not come on Oil warning indicator light come on Supply engine oil Engine oil level and electrical circuit are OK 1 ...

Page 52: ...ween maxi mum and minimum marks If the oil level is lower add sufficient oil to raise it to the proper level Do not add any chemical additives Transmission oil also lubricates the clutch and additives could cause clutch slippage Be sure no foreign material enters the crankcase TRANSMISSION OIL REPLACEMENT 1 Warm up the engine for several minutes 2 Place a container under the engine 3 Remove oil fi...

Page 53: ...pect Oil leaks Oil level NOTE Wipe off any oil spilled on the crankcase EAS00078 ADJUSTING THE CLUTCH CABLE FREE PLAY 1 Check clutch cable free play Out of specification Adjust 2 Adjust clutch cable free play Handlebar side a Loosen the locknut b Turn the adjusting bolt in direction a or b until the specified clutch cable free play is obtained Clutch cable free play at the end of the clutch lever ...

Page 54: ... b until the specified clutch cable free play is obtained c Tighten the locknuts Mechanism adjustment 1 Remove Brush guard 2 Loosen Locknuts 3 Turn the adjusters 4 Drain Coolant Refeer to the COOLANT REPLACEMENT section 5 Disconnect Outlet hose radiator 6 Remove Screw Water outlet pipe Direction a Clutch cable free play is increased Direction b Clutch cable free play is decreased Direction a Clutc...

Page 55: ...Adjustments steps Loosen the locknut Move the push lever toward the front with you finger until it stops With the push lever in this position turn the adjuster to align the mark on the end of the push lever with the mark protube rance on the crankcase Tighten the locknut 11 Install crankcase cover right brake pedal return spring Locknut 8 Nm 0 8 m kg 5 8 ft lb Screw crankcase cover 8 Nm 0 8 m kg 5...

Page 56: ... 12 Install Gasket Autolube pump cover 13 Connect Autolube pump hoses Autolube pump cable 14 Install Screw Water outlet pipe 15 Connect Outlet hose Radiator 16 Adjust Clutch cable free play Refer to the Cable free play adjustment section 17 Install Brush guard 18 Fill Crankcase Refer to the TRANSMISSION OIL REPLA CEMENT section 19 Fill Radiator Reservoir tank radiator Refer to the COOLANT REPLACEM...

Page 57: ...llects in this hose clean the air filter element and air filter case 1 Remove Side cover left 2 Remove air filter case cover screws air filter assembly Slide out guide together with element 3 Clean air filter element with solvent s s WARNING Never use low flash point solvents such as gasoline to clean the air filter element Such solvents may cause a fire or an explo sion NOTE After cleaning gently...

Page 58: ...ss oil The air filter element should be wet but not dripping 6 Install air filter element air filter element to element guide NOTE Install the washer with its bent fringe upwards as shown Air filter assembly Slide in guide to air case CAUTION Be sure to insert the element guide into the filter case with its handle located close to you and also pay attention to the seal sponge for damage 7 Install ...

Page 59: ...replacement 2 Check the tightening torque of the carbure tor joint securing bolts FUEL LINE INSPECTION 1 Inspect Fuel hose Cracks damage replace Loose connection Connect properly EAS00098 CHECKING THE CRANKCASE BREATHER HOSE 1 Check crankcase breather hose Cracks damage Replace Loose connection Connect properly CAUTION Make sure the crankcase breather hose is routed correctly Bolt Carburetor joint...

Page 60: ...Remove Autolube pump cover 2 Inspect Oil hose Oil delivery hose Cracks damage replace Loose connection Connect properly 3 Install Autolube pump cover COOLANT LEVEL INSPECTION 1 Place the machine in a level surface 2 Remove Side cover left 3 Inspect Coolant level Coolant level is under Low level line Add soft water tap water Coolant reservoir tank Nut Exhaust pipe 18 Nm 1 9 m kg 13 ft lb Screw Muff...

Page 61: ...EAS00105 CHANGING THE COOLANT 1 Remove side covers left and right exhaust pipe 2 Disconnect coolant reservoir hose 3 Drain coolant from the coolant reservoir 4 Remove radiator cap s s WARNING A hot radiator is under pressure Therefore do not remove the radiator cap when the engine is hot Scalding hot fluid and steam may be blown out which could cause serious injury When the engine has cooled open ...

Page 62: ...ant reservoir hose 10 Fill cooling system with the specified amount of the recom mended coolant Handling notes for coolant Coolant is potentially harmful and should be handled with special care s s WARNING If coolant splashes in your eyes tho roughly wash them with water and con sult a doctor If coolant splashes on your clothes quickly wash it away with water and then Coolant drain bolt engine 10N...

Page 63: ...tact with pain ted surfaces immediately wash them with water Do not mix different types of antifreeze 11 Install radiator cap 12 Fill coolant reservoir with the recommended coolant to the maximum level mark a 13 Install coolant reservoir cap 14 Start the engine warm it up for several minutes and then stop it 15 Check coolant level Refer to CHECKING THE COOLANT LEVEL NOTE Before checking the coolan...

Page 64: ...CHK ADJ COOLING SYSTEM INSPECTION 3 23 COOLING SYSTEM INSPECTION 1 Inspect radiator inlet hose outlet hose water outlet pipe cracks damage Replace Refer to the COOLING SYSTEM section ins CHAPTER 6 1 4 ...

Page 65: ...leeding the brake system Air in the brake system will consi derably reduce braking performance and could result in loss of control and possibly an accident Therefore check and if neces sary bleed the brake system CAUTION After adjusting the brake lever free play make sure there is no brake drag EAS00111 ADJUSTING THE REAR BRAKE 1 Check brake pedal position distance a from the top of the rider foo ...

Page 66: ...ke system Before the vehicle is operated the air must be removed by bleeding the brake system Air in the brake system will consi derably reduce braking performance and could result in loss of control and possibly an accident Therefore check and if neces sary bleed the brake system CAUTION After adjusting the brake pedal position make sure there is no brake drag 3 Adjust rear brake light switch Ref...

Page 67: ... may result in a harmful che mical reaction leading to poor brake performance When refilling be careful that water does not enter the brake fluid reservoir Water will significantly lower the boiling point of the brake fluid and could cause vapor lock CAUTION Brake fluid may damage painted surfaces and plastic parts Therefore always clean up any spilt brake fluid immediately NOTE In order to ensure...

Page 68: ...ear brake 4 Install Rubber plug EAS00128 ADJUSTING THE REAR BRAKE LIGHT SWITCH NOTE The rear brake light switch is operated by movement of the brake pedal The rear brake light switch is properly adjusted when the brake light comes on just before the braking effect starts 1 Check rear brake light operation timing Incorrect Adjust 2 Adjust rear brake light operation timing a Hold the main body of th...

Page 69: ...EAR BRAKES in chapter 4 EAS00139 ADJUSTING THE DRIVE CHAIN SLACK NOTE The drive chain slack must be checked at the tightest point on the chain CAUTION A drive chain that is too tight will overload the engine and other vital parts and one that is too loose can skip and damage the swingarm or cause an accident Therefore keep the drive chain slack within the speci fied limits 1 Stand the motorcycle o...

Page 70: ...the swin garm end plates and the ends of the swin garm c Tighten the wheel axle nut to specification d Tighten the locknuts to specification 7 Install cotter pin s s WARNING Always use a new cotter pin CAUTION Do not loosen the wheel axle nut after tigh tening it to the specified torque If the groo ve in the wheel axle nut is not aligned with the cotter pin hole in the wheel axle tighten the nut f...

Page 71: ... Wipe the drive chain dry and thoroughly lubricate it with engine oil or chain lubricant that is suita ble for O ring chains Do not use any other lubricants on the drive chain since they may contain solvents that could damage the O rings EAS00146 CHECKING AND ADJUSTING THE STEERING HEAD 1 Stand the motorcycle on a level surface s s WARNING Securely support the motorcycle so that there is no danger...

Page 72: ... and lower bearings Refer to STEERING HEAD in chapter 4 e Install the rubber washer f Install the upper ring nut g Finger tighten the upper ring nut then align the slots of both ring nuts If neces sary hold the lower ring nut and tighten the upper ring nut until their slots are aligned h Install the lock washer NOTE Make sure the lock washer tabs sit correctly in the ring nut slots 5 Install Insta...

Page 73: ...above procedure on the opposi te handlebar f If the steering head tension is out of speci fication both handlebars should be within specification remove the upper bracket and loosen or tighten the upper ring nut g Reinstall the upper bracket and measure the steering head tension again as descri bed above h Repeat the above procedure until the stee ring head tension is within specification i Grasp ...

Page 74: ...6 ADJUSTING THE REAR SHOCK ABSORBER ASSEMBLY s s WARNING Securely support the motorcycle so that there is no danger of it falling over Spring preload CAUTION Never go beyond the maximum or minimum adjustment positions 1 Adjust loosen the locknut adjust the spring preload a Adjust the spring preload with a ring nut wrench b Turn the adjusting ring in direction a or b Ring nut wrench 90890 01268 Dir...

Page 75: ...cessories and the anticipated riding speed Operation of an overloaded motorcycle could cause tire damage an accident or an injury NEVER OVERLOAD THE MOTORCYCLE Tire air pressure measured on cold tires DT125R Up to 90 kg 198 lb Front 150 kPa 21 8 psi 1 5 kgf cm2 Rear 175 kPa 25 4 psi 1 75 kgf cm2 90 kg 198 lb to maximum load Front 175 kPa 25 4 psi 1 75 kgf cm2 Rear 200 kPa 28 9 psi 2 kgf cm2 Maximu...

Page 76: ...the tube make sure the wheel rim band and tube are cente red in the wheel groove Patching a punctured tube is not recom mended If it is absolutely necessary to do so use great care and replace the tube as soon as possible with a good quality replacement s s WARNING After extensive tests the tires listed below have been approved by Yamaha Motor España S A for this model The front and rear tires sho...

Page 77: ... specifica tion EAS00169 CHECKING AND TIGHTENING THE SPOKES The following procedure applies to all of the spokes 1 Check spoke Bends damage Replace Loose Tighten Tap the spokes with a screwdriver NOTE A tight spoke will emit a clear ringing tone a loose spoke will sound flat Tire air valve stem front wheel only Valve stem lock nut 1 5 Nm 0 15 m kg 1 1 ft lb Front tire Manufacturer Model Size DT125...

Page 78: ... inner and outer cables s s WARNING Damaged outer cable may cause the cable to corrode and interfere with its movement Replace damaged outer cable and inner cables as soon as possible 1 Check outer cable Damage Replace 2 Check cable operation Rough movement Lubricate NOTE Hold the cable end upright and pour a few drops of lubricant into the cable sheath or use a suitable lubricating device 2 3 5 N...

Page 79: ...g parts of the levers and pedals EAS00172 LUBRICATING THE SIDESTAND Lubricate the pivoting point and metal to metal moving parts of the sidestand EAS00174 LUBRICATING THE REAR SUSPENSION Lubricate the pivoting point and metal to metal moving parts of the rear suspension Recommended lubricant SAE 10W30 Motor Oil Recommended lubricant SAE 10W30 Motor Oil Recommended lubricant Molybdenum disulfide gr...

Page 80: ... it can cause severe burns or permanent eye injury FIRST AID IN CASE OF BODILY CONTACT EXTERNAL Skin Wash with water Eyes Flush with water for 15 minu tes and get immediate medical attention INTERNAL Drink large quantities of water or milk followed with milk of magnesia beaten egg or vegetable oil Get immediate medical attention CAUTION This is a sealed battery Never remove the sealing caps becaus...

Page 81: ...then the positive battery lead 3 Remove battery 4 Check battery charge a Connect a pocket tester to the battery ter minals NOTE The charge state of an MF battery can be checked by measuring its open circuit vol tage i e the voltage when the positive bat tery terminal is disconnected No charging is necessary when the open circuit voltage equals or exceeds 12 8 V b Check the charge of the battery as...

Page 82: ...y Before removing the battery charger lead clips from the battery terminals be sure to turn off the battery charger Make sure the battery charger lead clips are in full contact with the battery termi nal and that they are not shorted A corroded battery charger lead clip may generate heat in the contact area and a weak clip spring may cause sparks If the battery becomes hot to the touch at any time...

Page 83: ...over Rear side cover right EAS00181 CHECKING THE FUSES The following procedure applies to all of the fuses CAUTION To avoid a short circuit always set the main switch to OFF when checking or repla cing a fuse 1 Remove Rear side cover right 2 Check fuse a Connect the pocket tester to the fuse and check the continuity NOTE Set the pocket tester selector to OHM MLT 1 b If the pocket tester indicates ...

Page 84: ...se with the wrong amperage rating may cause extensive damage to the electrical system cause the lighting and ignition systems to malfunction and could possibly cause a fire 4 Install Rear side cover right EAS00182 REPLACING THE HEADLIGHT BULB 1 Remove front cowling 2 Disconnect Couplers 3 Remove headlight bulb cover 4 Remove the headlight bulb holder accor ding to the drawing then remove the defec...

Page 85: ...rwise the transparency of the glass the life of the bulb and the luminous flux will be adversely affected If the headlight bulb gets soiled thoroughly clean it with a cloth moistened with alcohol or lacquer thinner 6 Install headlight bulb holder 7 Install headlight bulb cover 8 Connect Front cowling EAS00184 ADJUSTING THE HEADLIGHT BEAM 1 Adjust headlight beam vertically a Loosen screws and b Adj...

Page 86: ...CHAS ...

Page 87: ...4 ...

Page 88: ...PECTION AND REPAIR 4 23 ASSEMBLY 4 27 AIR BLEEDING 4 35 FRONT FORK 4 37 REMOVAL 4 38 DISASSEMBLY 4 38 INSPECTION 4 40 ASSEMBLY 4 41 STEERING HEAD AND HANDLEBAR 4 45 REMOVAL 4 46 INSPECTION 4 49 INSTALLATION 4 50 REAR SHOCK ABSORBER AND SWINGARM 4 55 HANDLING NOTES 4 57 NOTES ON DISPOSAL 4 57 REMOVAL 4 57 INSPECTION 4 62 SIDE CLEARANCE ADJUSTMENT 4 62 INSTALLATION 4 64 DRIVE CHAIN AND SPROCKETS 4 6...

Page 89: ...Lateral 0 5 mm 0 02 in Basic weight DT125RE DT125X With oil and full fuel tank 126 kg 134 kg Maximum load 178 kg 392 lb 180 kg 396 lb Cold tire pressure Up to 90 Kg 198 bf load 150kPa 180Kpa 1 5kgf cm2 21 8psi 1 8kgf cm2 26 1psi 90kg 198lbf Maximum load 175kPa 180Kpa 1 75kgf cm2 25 4psi 1 8kgf cm2 26 1psi Off road riding 150kPa 1 5kgf cm2 21 8psi DT125X A Tire Size 120 70 17 58H B Rim Size 17x3 00...

Page 90: ... there is no danger of it falling over NOTE Place the motorcycle on a suitable stand so that the front wheel is elevated 2 Remove Cable holder speedometer 3 Disconnect Speedometer cable 4 Loosen Nuts Axle holder 5 Remove Front wheel axle Front wheel Gear unit speedometer Spacer collar NOTE Do not apply the brake lever when removing the brake caliper 2 1 3 2 1 3 ...

Page 91: ...ELS in chapter 3 3 Check spokes Bends damage Replace Loose Tighten Tap the spokes with a screwdriver NOTE A tight spoke will emit a clear ringing tone a loose spoke will sound flat 4 Tighten spokes NOTE After tightening the spokes measure the front wheel runout 5 Measure front wheel radial runout front wheel lateral runout Over the specified limits Replace Front wheel radial runout limit 1 mm 0 04...

Page 92: ...cle After a tire has been repaired or repla ced be sure to tighten the tire air valve stem locknut to specification 7 Check wheel bearings Front wheel turns roughly or is loose Replace the wheel bearings oil seals Damage wear Replace 8 Replace wheel bearings oil seals a Clean the outside of the front wheel hub b Remove the oil seals with a flat head screwdriver NOTE To prevent damaging the wheel p...

Page 93: ...42 INSTALLING THE FRONT WHEEL 1 Lubricate wheel axle wheel bearings oil seal lips speedometer drive gear speedometer driven gear 2 Install speedometer gear unit NOTE Make sure the speedometer gear unit and the wheel hub are installed with the two projec tions meshed into the two slots respectively 3 Install front wheel NOTE Make sure the slot in the speedometer gear unit fits over the stopper on t...

Page 94: ...er s s WARNING Make sure the brake cable is routed pro perly CAUTION Before tightening the wheel axle nut push down hard on the handlebar several times and check if the front fork rebounds smo othly 45 70 Nm 4 5 7 0 m kg 33 51 3 ft lb 7 5 12 Nm 0 75 1 2 m kg 5 5 8 8 ft lb ...

Page 95: ...C Rim Runout Vertical 1 0 mm 0 08 in Lateral 0 5 mm 0 02 in Basic weight DT125RE DT125X With oil and full fuel tank 126 kg 134 kg Maximum load 178 kg 392 lb 180 kg 396 lb Cold tire pressure Up to 90 Kg 198 bf load 175kPa 200Kpa 1 75kgf cm2 25 4psi 2 0kgf cm2 28 9psi 90kg 198lbf Maximum load 200kPa 200Kpa 2 0kgf cm2 28 9psi 2 0kgf cm2 28 9psi Off road riding 175kPa 1 75kgf cm2 25 4psi DT125X A Tire...

Page 96: ... of it falling over NOTE Place the motorcycle on a suitable stand so that the rear wheel is elevated 2 Remove rear brake caliper protection NOTE Do not depress the brake pedal when remo ving the brake caliper 3 Loosen bolts swingarm end 4 Remove wheel axle nut wheel axle rear wheel NOTE Push the rear wheel forward and remove the drive chain from the rear wheel sprocket 1 2 1 1 ...

Page 97: ... WHEEL INSPEC TION section 3 Measure Wheel runout Refer to the FRONT WHEEL INSPEC TION section 4 Check Wheel bearings Refer to the FRONT WHEEL INSPEC TION section 5 Check Wheel balance Refer to the FRONT WHEEL INSPEC TION section EAS00572 INSTALLING THE REAR WHEEL When installing the rear wheel reverse the removal procedure Note the following points 1 Lubricate wheel axle wheel bearings oil seal l...

Page 98: ... DRIVE CHAIN SLACK ADJUSTMENT section in CHAPTER 3 3 Tighten wheel axle nut bolts swingarm end Drive chain slack DT125RE 40 55mm 1 77 2 16in DT125X 25 40mm 0 98 1 58 in Recommended lubricant Lithium soap based grease 80 100Nm 8 0 10 0 m kg 58 7 73 3 ft lb 30 Nm 3 m kg 22 ft lb 1 ...

Page 99: ...liper Pad spring Piston Piston seal 10 Dust seal 11 Brake pad 12 Brake disc 26 Nm 2 6 m kg 19ft lb D USE NEW ONE 6 Nm 0 6 m kg 4 3ft lb 18 Nm 1 8 m kg 13ft lb D USE NEW ONE 20 Nm 2 0m kg 14ft lb 35 Nm 3 5 m kg 25ft lb D USE NEW ONE A Brake Fluid Type DOT 4 or DOT 3 B Brake pad Wear Limit 0 8 m 0 03 in C Brake Disc Wear Limit 3mm 0 12 in ...

Page 100: ...hose 10 Brake caliper 11 Piston 12 Piston seal 13 Dust seal 14 Shim 15 Pad spring 16 Brake pads 17 Brake disc A Brake Fluid Type DOT 4 or DOT 3 B Brake pad Wear Limit 0 8 m 0 03 in C Brake Disc Wear Limit 4mm 0 16 in 18 Nm 1 8 m kg 13ft lb D USE NEW ONE 6 Nm 0 6 m kg 4 3ft lb D USE NEW ONE 26 Nm 2 6 m kg 19ft lb 10 Nm 1 0 m kg 7 2ft lb 4 Nm 0 4 m kg 2 9ft lb D USE NEW ONE ...

Page 101: ...omponents Use only clean or new brake fluid for cle aning brake components Brake fluid may damage painted surfa ces and plastic parts Therefore always clean up any spilt brake fluid immedia tely Avoid brake fluid coming into contact with the eyes as it can cause serious injury FIRST AID FOR BRAKE FLUID ENTERING THE EYES Flush with water for 15 minutes and get immediate medical attention EAS00581 R...

Page 102: ...all new brake pads and a new brake pad spring as a set a Connect a clear plastic hose tightly to the bleed screw Put the other end of the hose into an open container b Loosen the bleed screw and push the brake caliper pistons into the brake caliper with your finger c Tighten the bleed screw d Install new brake pads and a new brake pad spring Brake pad wear limit 0 8 mm 0 03 in Bleed screw 6 Nm 0 6...

Page 103: ... recommended brake fluid to the proper level Refer to CHECKING THE BRAKE FLUID LEVEL in chapter 3 9 Check brake lever operation Soft or spongy feeling Bleed the brake system Refer to BLEEDING THE HYDRAULIC BRAKE SYSTEM in chapter 3 EAS00583 REPLACING THE REAR BRAKE PADS NOTE When replacing the brake pads it is not necessary to disconnect the brake hose or disassemble the brake caliper Recommended ...

Page 104: ...stall brake pad shims onto the brake pads brake pad springs brake pads NOTE Always install new brake pads brake pad shims and a brake pad spring as a set a Connect a clear plastic hose tightly to the bleed screw Put the other end of the hose into an open container b Loosen the bleed screw and push the brake caliper pistons into the brake caliper with your finger c Tighten the bleed screw Brake pad...

Page 105: ...7 Check brake fluid level Below the minimum level mark Add the recommended brake fluid to the proper level Refer to CHECKING THE BRAKE FLUID LEVEL in chapter 3 8 Check brake pedal operation Soft or spongy feeling Bleed the brake system Refer to BLEEDING THE HYDRAULIC BRAKE SYSTEM in chapter 3 18 Nm 1 8 m kg 13ft lb 1 1 ...

Page 106: ...the entire brake system 1 Remove union bolt copper washers brake hose NOTE Put the end of the brake hose into a container and pump out the brake fluid carefully 2 Remove Retaining bolt caliper body Brake pads Pad springs Refer to the BRAKE PAD REPLACE MENT section 3 Remove Caliper body Caliper bracket 4 Remove Caliper piston Clip Dust seal Piston seal 2 1 2 1 2 1 2 ...

Page 107: ...e clip using a thin screwdriver CAUTION When removing the clip take care not to damage the dust seal and caliper body c Remove the brake caliper piston seals EAS00626 DISASSEMBLING THE REAR BRAKE CALIPER NOTE Before disassembling the brake caliper drain the brake fluid from the entire brake system 1 Remove Protector Caliper body Union bolts Copper washers Retaining bolt Caliper body NOTE Put the e...

Page 108: ...tion Caliper bracket 5 Remove Caliper piston Dust seal Piston seal a Blow compressed air into the brake hose joint opening a to force out the piston from the brake caliper s s WARNING Cover the brake caliper piston with a rag Be careful not to get injured when the piston is expelled from the brake caliper Never try to pry out the brake caliper pis ton b Remove the brake caliper piston seals 3 1 2 ...

Page 109: ...inder drain the brake fluid from the entire brake system 1 Remove Brake switch Brake lever Return spring brake lever NOTE When removing the brake switch push the switch hook using a suitable rod then pull it out 2 Pull back the brake hose cover from the master cylinder 3 Remove Union bolt Cooper washers 4 Remove Bracket master cylinder Master cylinder 2 3 1 2 3 1 ...

Page 110: ... cylinder kit NOTE To collect any remaining brake fluid place a container under the master cylinder and the end of the brake hose DISASSEMBLING THE REAR BRAKE MASTER CYLINDER 1 Remove Brake hose guides 2 Loosen Union bolt 3 Remove Cotter pin Washer Cotter pin Screw Reservoir tank Bolts master cylinder Master cylinder with brake hose and reservoir tank 1 8 7 7 6 1 ...

Page 111: ...er cap reservoir tank Diaphragm NOTE To collect any remaining brake fluid place a container under the master cylinder and the end of the brake hose EAS00630 CHECKING THE FRONT AND REAR BRAKE CALIPER Recommended brake component replacement schedule Brake pads If necessary Piston seals Every two years Brake hose Every four years Brake fluid Every two years and whenever the brake is disassembled 1 3 ...

Page 112: ...ssembly brake fluid delivery passage brake caliper body Obstruction Blow out with compressed air s s WARNING Whenever a brake caliper is disassembled replace the piston seals 2 Check Caliper body Caliper bracket Cracks damage Replace Oil delivery passage caliper body Blow out with compressed air Slide collar caliper body Guide shaft caliper bracket Rust wear damage Replace Slider boot caliper body...

Page 113: ...age caliper body Blow out with compressed air A Front B Rear 4 Check Master cylinder kit Scratches Wear Damage Replace A Front B Rear 5 Check Reservoir tank Cracks damage Replace Diaphragm Front Wear damage Replace 6 Check Brake hoses Cracks wear damage Replace 7 Measure Brake pads thickness a Out of specification Replace Wear indicator Brake pad wear limit 0 8 mm 0 03 in 1 1 2 1 ...

Page 114: ... limit 8 Inspect Brake disc Galling damage Replace 9 Measure Brake disc deflection Out of specification Inspect wheel runout If wheel runout is in good condition repla ce Brake disc thickness Out of specification Replace Dial gauge A Front B Rear Maximum deflection 0 15mm 0 006in Minimum thickness Front 3 0mm 0 12in Rear 4 0mm 0 16in Bolt brake disc 20 Nm 2 0 m kg 14ft lb Use LOCTITE 1 ...

Page 115: ...ls to swell and distort Whenever a brake caliper is disassem bled replace the brake caliper piston seals Front brake 1 Install Master cylinder kit Circlip Dust boot 2 Install Master cylinder NOTE Install the master cylinder bracket with the UP mark facing upward Tighten first the upper bolt then the lower bolt 3 Install Return spring brake lever Brake lever Brake switch NOTE Apply lithium soap bas...

Page 116: ...rectly 5 Install Caliper bracket 6 Install Pad springs Brake pads Refer to the BRAKE PAD REPLACE MENT section 7 Install Caliper body NOTE Apply the lithium soap base grease onto the caliper guide shaft and retaining bolt CAUTION Take care no to allow the brake pads to be smeared by grease Wipe off any unnecessary grease that comes out of place Caliper bracket 35 Nm 3 5 m kg 25ft lb Retaining bolt ...

Page 117: ...ces and plastic parts Therefore always clean up any spilt brake fluid immediately s s WARNING Use only the designated brake fluid Other brake fluids may cause the rubber seals to deteriorate causing leakage and poor brake performance Refill with the same type of brake fluid that is already in the system Mixing brake fluids may result in a harmful che mical reaction leading to poor brake performanc...

Page 118: ...e minimum level mark a Add the recommended brake fluid to the proper level Refer to BRAKE FLUID INSPECTION in chapter 3 Lower level line 12 Install Diaphragm Cap Master cylinder 13 Adjust Front brake lever free play Refer to the FRONT BRAKE ADJUST MENT section in chapter 3 Screw Master cylinder 2 Nm 0 2m kg 1 4ft lb Free play 2 5mm 0 08 0 20in 1 2 a 2 1 3 ...

Page 119: ...orarily tighten the union bolt s s WARNING Always use a new cooper washer 2 Install Master cylinder Reservoir tank Pin Washer Cotter pin Brake hose guides NOTE Apply the lithium soap base grease to the pin s s WARNING Always use a new cotter pin 3 Install Piston seal Dust seal Caliper piston s s WARNING Always use new piston seal and dust seal Bolt Master cylinder 10 Nm 1 0 m kg 7 2 ft lb Screw Re...

Page 120: ...e boss on the swingarm correctly engages with the locating slot on the caliper bracket 5 Install Pad springs Brake pads Shim Refer to the BRAKE PAD REPLACE MENT section 6 Install Caliper body NOTE Apply the lithium soap base grease onto the caliper guide shaft and retaining bolt CAUTION Take care not to allow the brake pads to be smeared by grease Wipe off any unnecessary grease that comes out of ...

Page 121: ... Therefore always clean up any spilt brake fluid immediately s s WARNING Use only the designated brake fluid Other brake fluids may cause the rubber seals to deteriorate causing leakage and poor brake performance Refill with the same type of brake fluid that is already in the system Mixing brake fluids may result in a harmful che mical reaction leading to poor brake performance When refilling be c...

Page 122: ...Refer to BRAKE FLUID INSPECTION in chapter 3 Lower level line 11 Install Diaphragm Inner cap Reservoir tank Cap Master cylinder 12 Adjust Rear brake pedal height a Refer to the REAR BRAKE ADJUST MENT section 13 Adjust Drive chain slack a Refer to the DRIVE CHAIN SLACK ADJUSTMENT section in chapter 3 Pedal height 15mm 0 95in Below top of footrest Drive chain slack DT125RE 40 55mm 1 77 2 16in DT125X...

Page 123: ...d allow air to enter the hydraulic brake system considerably lengt hening the bleeding procedure If bleeding is difficult it may be necessary to let the brake fluid settle for a few hours Repeat the bleeding procedure when the tiny bubbles in the hose have disappeared 1 Bleed hydraulic brake system a Fill the brake fluid reservoir to the proper level with the recommended brake fluid b Install the ...

Page 124: ...lease the brake lever or brake pedal i Repeat steps e to h until all of the air bub bles have disappeared from the brake fluid in the plastic hose j Tighten the bleed screw to specification k Fill the brake fluid reservoir to the proper level with the recommended brake fluid Refer to CHECKING THE BRAKE FLUID LEVEL s s WARNING After bleeding the hydraulic brake system check the brake operation Blee...

Page 125: ...13 Slide bush 14 Outer fork tube 15 Axle holder 16 Fork boot C USE NEW ONE 23 Nm 2 3m kg 17ft lb 30 Nm 3 0 m kg 22ft lb A FOR OIL EACH CAPACITY 495 cm3 GRADE FOR OIL 10W OR EQUIVALENT OIL LEVEL 165 5mm Below the top of inner tube fully rebounded without fork spring 62 Nm 6 2 m kg 45ft lb 10 Nm 1 0 m kg 7 2ft lb LT B FOR SPRING MINIMUM FREE LENGTH 503mm C USE NEW ONE ...

Page 126: ...le stand under the engine 2 Remove Brake caliper assembly 3 Loosen upper bracket pinch bolt cap bolt lower bracket pinch bolt s s WARNING Before loosening the upper and lower brac ket pinch bolts support the front fork leg 4 Remove front fork leg DISASSEMBLY 1 Remove Clamps Upper and lower Fork boot 2 Remove Cap bolt Spacer Spring seat Fork spring 1 3 2 1 2 3 4 2 1 3 ...

Page 127: ...er Washer CAUTION Take care not to scratch the inner tube 5 Remove Bolt Damper rod Cooper washer NOTE Hold the damper rod to loosen the bolt Damper rod by the T handle and the Holder 6 Remove Damper rod Rebound spring Out of inner fork tube Damper rod holder 90890 01388 T handle 90890 01326 1 2 2 1 3 1 2 ...

Page 128: ... damaged oil seal or bus hing must be replaced Avoid bottoming the inner tube into the outer tube during the above procedure as the oil flow stopper will be damaged EAS00656 CHECKING THE FRONT FORK LEGS The following procedure applies to both of the front fork legs 1 Check inner tube outer tube Bends damage scratches Replace s s WARNING Do not attempt to straighten a bent inner tube as this may da...

Page 129: ... s s WARNING Make sure the oil levels in both front fork legs are equal Uneven oil levels can result in poor hand ling and a loss of stability NOTE When assembling the front fork leg be sure to replace the following parts inner tube bushing outer tube bushing oil seal dust seal Before assembling the front fork leg make sure all of the components are clean 1 Install damper rod assembly CAUTION Allo...

Page 130: ...l outer tube bushing with the fork seal driver weight and fork seal driver attachment 5 Install washer oil seal with the fork seal driver weight and fork seal driver attachment CAUTION Make sure the numbered side of the oil seal faces up Recommended lubricant Fork oil 10W or equivalent 62 Nm 6 2 m kg 45 ft lb LOCTITE Damper rod holder 90890 01388 T handle 90890 01326 Fork seal driver weight 90890 ...

Page 131: ...seal clip NOTE Adjust the oil seal clip so that it fits into the outer tube s groove 7 Install dust seal with the fork seal driver weight 8 Fill front fork leg with the specified amount of the recom mended fork oil Fork seal driver weight 90890 01367 Quantity each front fork leg DT125RE 0 495 L DT125X 0 6 L Recommended oil Yamaha fork and shock oil 10W or equivalent Front fork leg oil level from t...

Page 132: ...ht After filling slowly pump the front fork leg up and down to distribute the fork oil 9 Install spring spring seat spacer cap bolt NOTE Install the spring with the smaller pitch facing up Before installing the cap bolt lubricate its O ring with grease Temporarily tighten the cap bolt 4 3 2 1 ...

Page 133: ...own Ring nut 10 Cover 11 Bearing race 12 Headlight stay A TIGHTENING STEPS Tightening ring nut 35Nm to 40Nm 3 5 to 4 0 m kg 25 6 to 29 3 ft lb Loosen it fully Retighten it 3Nm to 5Nm 0 3 to 0 5 m kg 2 2 to 3 6 ft lb 120 to 155 Nm 12 to 15 5 m kg 88 to 110 ft lb 12 to 28 Nm 1 2 to 2 8 m kg 8 8 to 20 5 ft lb 120 to 155 Nm 12 to 15 5 m kg 88 to 110 ft lb ...

Page 134: ...le so there is no danger of falling over 2 Remove Front wheel Refer to the FRONT WHEEL REMOVAL section Front fork Refer to the FRONT FORK REMOVAL section 3 Remove Bolts front fender Front fender Washers 4 Remove Headlight cover Headlightn lens unit 5 Disconnect Headlight lead Auxiliary light lead 6 Disconnect Flasher light leads 2 3 2 1 1 ...

Page 135: ...e hose guide From left side only 8 Disconnect Speedometer cable 9 Remove Bands 10 Disconnect Meter leads Handlebar switch leads Main switch leads Flasher relay leads 11 Remove Bands Master cylinder assembly 12 Remove Brush guard 13 Disconnect Clutch cable from clutch cable pivot 14 Remove Meter assembly 1 2 3 1 1 4 ...

Page 136: ...removal of the handlebar be sure to clear the throttle cable housing 17 Remove Flange nut Handlebar crown 18 Remove Lock washer Ring nut 1 Ring nut 2 Cover NOTE Remove the ring nut using the Ring Nut wrench s s WARNING Support the lower bracket so that it may not fall down Ring Nut Wrench 90890 01403 1 1 2 1 2 1 2 3 4 ...

Page 137: ...n the head pipe using a long rod and the hammer as shown Remove the bearing race on the steering stern using the floor chinsel and the hammer as shown Install the new dust seal and races NOTE Always replace bearings and races as a set Replace the dust seat whenever the stee ring head is disassembled CAUTION If the bearing race is fitted not squarly the head pipe could be damaged 3 Inspect Handleba...

Page 138: ...ft to a new handlebar Apply a light coat of an adhesive for rub ber on the left handlebar end Install the handlebar grip NOTE Wipe off any excess adhesive with a clear rag s s WARNING Leave the handlebar intact until the adhesi ve becomes dry enough to make the grip and handlebar stuck securely INSTALLATION Reverse the REMOVAL procedures Note the following points 1 Lubricate Bearing races Bearings...

Page 139: ...ue wrench to the right nut wrench so that they form a right angle Loosen the ring nut fully Retighten the ring nut using the Ring Nut Wrench s s WARNING Avoid over tightening 5 Install Handlebar crown Flange nut Steering stem NOTE Temporarily tighten the flange bol Ring Nut Wrench 90890 01403 Ring Nut Initial tightening 35Nm to 40Nm 3 5 to 4 0 m kg 25 6 to 29 3 ft lb Ring Nut Final tightening 3Nm ...

Page 140: ...the brake hose guide to the left side only On the left side install the flasher light having a chocolate color lead Next install the other flasher light with a dark green color lead Bolt Meter assembly 5Nm to 8Nm 0 5 to 0 8 m kg 3 6 to 5 8 ft lb Pinch Bolt Under Bracket 20 to 25Nm 2 0 to 2 5 m kg 14 6 to 18 3 ft lb Flange nut Steering stem 120 to 155 Nm 12 a 15 5 m kg 88 to 110ft lb Pinch bolt Han...

Page 141: ...r crown apply a light coat of lithium soap base grease onto the handlebar end and install the throttle housing to the handlebar 10 Install Brake master cylinder NOTE Install the master cylinder bracket with the UP mark facing upward Tighten first the upper bolt then the lower bolt 11 Install Clutch cable NOTE Apply a light coat of lithium soap base grease onto the clutch cable end Bolt Handlebar h...

Page 142: ...the FRONT WHEEL INSTALLA TION section 14 Adjust Clutch cable free play Refer to the CLUTCH ADJUSTMENT section in chapter 3 Front wheel axle 80 to 100 Nm 8 0 a 10 0 m kg 58 6 to 73 3ft lb Axle security bolts 7 5 to 12 Nm 0 75 to 1 2 m kg 5 5 to 8 8 5ft lb Free play 2 3mm 0 08 0 12in 3 1 2 ...

Page 143: ...k absorber assembly Spring Bush A SPRING PRELOAD INSTALLED FOR DT125RE STANDARD LENGTH 230 mm MINIMUM LENGTH 220 mm MAXIMUM LENGTH 235 mm 30 to 35 Nm 3 0 to 3 5 m kg 22 to 25 6 ft lb A SPRING PRELOAD INSTALLED FOR DT125X STANDARD LENGTH 244 mm MINIMUM LENGTH 234 mm MAXIMUM LENGTH 249 mm ...

Page 144: ...aring Oil seal 10 Bush 11 Plain washer 12 Shim 13 Thrust cover 45 to 70 Nm 4 5 to 7 m kg 33 to 51 3 ft lb 45 to 70 Nm 4 5 to 7 m kg 33 to 51 3 ft lb 80 to 100 Nm 8 to 10 m kg 58 6 to 73 3 ft lb 3 to 5 Nm 0 3 to 0 5 m kg 2 2 to 3 6 ft lb 2 to 4 Nm 0 2 to 0 4 m kg 1 46 to 2 9 ft lb 3 to 5 Nm 0 3 to 0 5 m kg 2 2 to 3 6 ft lb ...

Page 145: ...ber to an open flame or any other source of high heat High heat can cause an explo sion due to excessive gas pressure Do not deform or damage the rear shock absorber in any way Rear shock absor ber damage will result in poor damping performance EAS00688 DISPOSING OF A REAR SHOCK ABSORBER Gas pressure must be released before dispo sing of a rear shock absorber To release the gas pressure drill a 2 ...

Page 146: ...wingarm from swingarm side 3 Remove Bolt Shock absorber Lower s s WARNING When removing the lower bolt hold the swingarm so that it does not drop down wards when the lower bolt is removed 4 Remove Bolt Shock absorber Upper 5 Remove Rear shock absorber NOTE Pull up the swingarm then remove the rear shock absorber through between the swin garm and relay arm 1 2 1 1 ...

Page 147: ...over 1 Elevate the rear wheel by placing a suitable stand under the engine 2 Remove Rear shock absorber Refer to the REAR SHOCK ABSORBER section 3 Remove Rear wheel Refer to the REAR WHEEL REMOVAL section 4 Remove Brake hose guides Mud guard 5 Remove Protector Brake caliper Brake caliper assembly 6 Remove Chain case Chain guide Chain guard 3 1 2 2 1 1 ...

Page 148: ...e check the inner collar bearing bushing and thrust over or adjust the shim Check the swingarm vertical movement by moving it up and down If vertical movement is tight binding or rough check the inner collar bearing bus hing and thrust cover or adjust the shim 8 Remove Pivot shaft Swingarm 9 Remove Connecting arm Nut Swingarm Pivot shaft 80 to 100Nm 8 to 10 m kg 58 6 to 73 3lb ft Side play At the ...

Page 149: ...CHAS REMOVING THE SWINGARM ASSEMBLY 4 61 10 Remove Relay arm 11 Remove Chain protector 12 Remove Thrust covers Inner collars Swingarm Inner collars Connecting arm Inner collar Relay arm 1 2 1 4 2 2 1 3 ...

Page 150: ...assembly spring Damage wear Replace the rear shock absorber assembly bushings Damage wear Replace dust seals Damage wear Replace bolts Bends damage wear Replace EAS00707 CHECKING THE SWINGARM 1 Check swingarm Bends cracks damage Replace 2 Check pivot shaft Roll the pivot shaft on a flat surface Bends Replace s s WARNING Do not attempt to straighten a bent pivot shaft 3 Wash pivot shaft dust covers...

Page 151: ...4 Check dust covers spacer washers oil seals Damage wear Replace bearings Damage pitting Replace 5 Check connecting arms relay arm Damage wear Replace 6 Check bearings oil seals Damage pitting Replace 1 3 4 2 2 4 3 1 1 1 2 9 8 2 1 1 2 ...

Page 152: ...ivot shaft 2 Install relay arm connecting arms NOTE Install the connecting arm front bolt from the right 3 Install rear shock absorber assembly rear wheel Refer to INSTALLING THE REAR SHOCK ABSORBER ASSEMBLY and INSTA LLING THE REAR WHEEL 45 to 70 Nm 4 5 to 7 0m kg 33 to 95 5ft lb Recommended lubricant Molybdenum disulfide grease 45 to 70 Nm 4 5 to 7 0m kg 33 to 95 5ft lb ...

Page 153: ...CHAS INSTALLING THE SWINGARM 4 65 4 Adjust drive chain slack Refer to ADJUSTING THE DRIVE CHAIN SLACK in chapter 3 Drive chain slack DT125RE 40 55mm 1 77 2 16in DT125X 25 40mm 0 98 1 58 in ...

Page 154: ...AIN AND SPROCKETS Drive sprocket Chain joint Drive chain 32 to 37 Nm 3 2 to 3 7 m kg 23 5 to 27 1 ft lb A DRIVE CHAIN B TYPE 428V2 C No OF LINKS 134 D DRIVE CHAIN SLACK DT125RE 45 55mm 1 77 2 16in E DRIVE CHAIN SLACK DT125X 25 40mm 0 984 1 575in ...

Page 155: ...e stand so that the rear wheel is elevated 2 Remove Crankcase cover left 3 Straighten Lock washer tab 4 Loosen Nut drive sprocket NOTE When loosening the drive sprocket nut apply the rear brake pedal and transmission gear to the 6th position 5 Remove Clip master link Plate master link master link O rings Drive chain 6 Remove Chain guide Drive sprocket 7 Remove Rear wheel Refer to the REAR WHEEL RE...

Page 156: ... the drive chain Out of specification Replace the drive chain 2 Check drive chain Stiffness Clean and lubricate or repla ce 3 Clean drive chain a Wipe the drive chain with a clean cloth b Put the drive chain in kerosene and remove any remaining dirt c Remove the drive chain from the kerosene and completely dry it Ten link drive chain section limit maximum 120 mm 4 72 in ...

Page 157: ...drive chain in kerosine more them ten minutes O ring is damage by kerosine 4 Check O rings Damage Replace the drive chain drive chain rollers Damage wear Replace the drive chain drive chain side plates Damage wear Replace the drive chain Cracks Replace the drive chain and make sure the battery breather hose is properly routed away from the drive chain and below the swingarm 5 Lubricate drive chain...

Page 158: ...ring master link plate with a drive chain cutter CAUTION Never install a new drive chain onto worn drive chain sprockets this will dramatically shorten the drive chain s life 4 Adjust drive chain slack Refer to ADJUSTING THE DRIVE CHAIN SLACK in chapter 3 Recommended lubricant Engine oil or chain lubricant sui table for O ring chains 60 Nm 6 0 m kg 43 ft lb Drive chain slack DT125RE 45 55 mm 1 77 ...

Page 159: ...71 CAUTION A drive chain that is too tight will overload the engine and other vital parts and one that is too loose can skip and damage the swingarm or cause an accident Therefore keep the drive chain slack within the speci fied limits ...

Page 160: ...ENG ...

Page 161: ...5 ...

Page 162: ...CRANKSHFT 5 15 POWER VALVE 5 15 AUTOLUBE PUMP ASSEMBLY 5 16 INSPECTION AND REPAIR 5 17 CYLINDER HEAD 5 17 CYLINDER AND PISTON 5 18 PISTON RINGS 5 19 PISTON PIN AND BEARING 5 21 CLUTCH 5 21 PRIMARY DRIVE 5 24 TRANSMISSION AND SHIFTER 5 25 SHIFT SHAFT AND STOPPER LEVER 5 27 CRANKSHAFT 5 27 AUTOLUBE PUMP 5 28 POWER VALVE 5 29 CRANKCASE 5 30 ENGINE ASSEMBLY AND ADJUSTMENTS 5 31 AUTOLUBE PUMP 5 31 POWE...

Page 163: ...der Piston and piston ring Power valve Clutch Primary drive gear Kick axle Shift shaft Magneto rotor Stator Autolube pump SIDE COVERS 1 Remove Side cover right Side cover left Seat COOLANT 1 Drain Coolant Refer to the COOLANT REPLACEMENT section in chapter 3 TRANSMISSION OIL 1 Drain Transmission oil Refer to the TRANSMISSION OIL REPLA CEMENT section in chapter 3 ...

Page 164: ...RETOR REMOVAL section in chapter 6 AUTOLUBE PUMP CABLE AND HOSE 1 Remove Autolube pump cover 2 Disconnect hose from autolube pump and hose guide Gasket autolube pump cover NOTE Plug the oil hose so that oil will not run out of the oil tank 3 Remove Pump cable NOTE Turn the pump pulley clockwise by finger to make the pump cable loose enough for its end to be removed from the pulley 1 1 2 1 1 2 1 3 ...

Page 165: ... Y P V S CABLES 1 Remove Pulley cover Power valve 2 Remove Pulley Power valve Removal steps Loosen both locknuts and turn in both adjusters Insert a pin Ø4mm Ø0 16in through the aligning indent in the pulley and into the hole to lock the pulley Remove the pulley from the power valve and then disconnect the Y P V S cables from the pulley Remove the pin 1 2 5 5 1 4 2 3 4 2 1 3 ...

Page 166: ... leads 4 Remove Servomotor unit Adjuster Y P V S cable Pulley housing RADIATOR HOSES 1 Disconnect Radiator hose Inlet 2 Disconnect Radiator hose Outlet LEADS 1 Disconnect Battery lead Negative 2 Disconnect Spark plug lead Thermo unit lead 1 3 2 1 1 2 1 ...

Page 167: ... 2 Straighten Lock washer tab 3 Loosen Nut Drive sprocket NOTE When loosening the nut Drive sprocket apply the rear brake pedal and transmission gear to the 6th position 4 Remove Drive chain Nut Drive sprocket Lock washer Drive sprocket Spacer collar ENGINE REMOVAL 1 Remove Bolts Engine stay Upper Bolts Engine mount Front 2 1 1 2 1 1 5 4 2 3 1 2 ...

Page 168: ...but for enough to set the engine free 3 Remove Engine assembly from right side ENGINE DISASSEMBLY CYLINDER HEAD CYLINDER AND PISTON NOTE With the engine mounted the cylinder head cylinder and piston can be maintained by removing the following parts Side covers Right and left Seat Radiator cover Oil tank cover Fuel tank Radiator hose inlet Servomotor unit Y P V S Engine stay Upper Exhaust pipe 1 Re...

Page 169: ...d 3 Remove Cover thermostatic valve 4 Remove Gasket Thermostatic valve O ring 5 Remove Cylinder head Gasket Cylinder head NOTE Loosen the nuts starting with the highest numbered one Loosen each nut 1 4 turn and remove them after all nuts are loosened 6 Remove Clutch cable guide Cylinder Gasket Cylinder Dowel pins NOTE Loosen each nut 1 4 turn and remove them after all nuts are loosened 2 1 3 2 1 5...

Page 170: ...ston s pin bore area If both areas are deburred and the piston pin is still difficult to remo ve remove it with the piston pin puller set 2 Remove top ring 2nd ring oil ring NOTE When removing a piston ring open the end gap with your fingers and lift the other side of the ring over the piston crown CLUTCH PRIMARY DRIVE GEAR AND BALANCER GEAR NOTE With the engine mounted the clutch primary drive ge...

Page 171: ...ver Right Dowel pins Gasket Crankcase cover 3 Remove Bolts Clutch springs Pressure plate Push rod 1 Friction plates Clutch plates Clutch dumper Nut Clutch boss Lock washer Clutch boss 10 Thrust washer 11 Clutch housing 12 Thrust plate 13 Conical spring washer 14 Boll 15 Push rod 2 16 1 2 3 8 9 7 6 5 10 11 12 13 14 4 15 16 2 1 ...

Page 172: ... Nut Balancer gear NOTE Hold the magneto rotor to loosen the nut pri mary drive gear and nut Balancer driven gear by the universal rotor holder 6 Remove Nut Balancer driven gear Lock washer Driven gear Balancer weight Straight key Nut Primary drive gear Plain washer Primary drive gear Baffle plate 7 Remove Drive gear Balancer weight Straight key Universal Clutch Holder 90890 04086 Universal Rotor ...

Page 173: ...d the shift shaft can be maintained by removing the following parts Brake pedal Radiator hose Outlet Autolube pump cable and hoses Crankcase cover Right Clutch 1 Remove Shift shaft CAUTION When removing the shift shaft hold the guide bar shift fork 2 in place Otherwise the guide bar will come loose with the shift shaft leaving the shift fork out of order in the crankcase 2 Remove Stopper lever Ret...

Page 174: ...the rotor to loosen the nut Rotor by the Universal Rotor Holder 2 Remove Rotor Woodruff key 3 Disconnect Neutral switch lead 4 Remove Stator REED VALVE NOTE With the engine mounted the reed valve can be maintained by removing the following parts Side covers Right and Left Seat Radiator cover Oil tank cover Fuel tank Carburetor Universal Rotor Holder 90890 01235 Rotor Puller 90890 01189 ...

Page 175: ...ating Tool NOTE Fully tighten the tool holding bolts but make sure the tool body is parallel with the case If necessary one screw may be backed out slightly to evel tool body As pressure is applied alternately tap on the front engine mounting boss transmis sion shafts and shift cam Then remove the crankcase Right NOTE Turn the shift cam to the position shown in the figure so that it doesn t contac...

Page 176: ...screw realign and start over If the cases don t separate check for a remaining case screw or fit ting Don t force 2 Remove Dowel pins Damper collar 3 Remove Bearing retainer SHIFTER TRANSMISSION AND BALANCER WEIGHT 1 Remove Guide bars Shift cam Shift forks NOTE Note the position of each part Pay particular attention to the location and direction of shift forks 2 Remove Transmission assembly Tap li...

Page 177: ... holding bolts but make sure the tool body is parallel with the case If necessary one screw may be bac ked out slightly to level tool body POWER VALVE NOTE With the engine mounted the power valve can be maintained by removing the following parts Side covers Seat Radiator cover Cover engine oil tank Fuel tank Servomotor unit Crankcase Separating Tool 90890 01135 1 1 2 ...

Page 178: ... inserting a wooden pice into the exhaust port 3 Remove Power valve Right Power valve Left Dowel pins Holder Power valve Gasket seal AUTOLUBE PUMP ASSEMBLY NOTE With the engine mounted the autolube pump assembly can be maintained by removing the following parts Brake pedal Radiator hose Outlet Autolube pump cable and hoses Kick crank Crankcase cover Right 2 1 2 1 3 2 ...

Page 179: ...CKING THE CYLINDER HEAD 1 Eliminate combustion chamber carbon deposits with a rounded scraper NOTE Do not use a sharp instrument to avoid dama ging or scratching spark plug bore threads valve seats 2 Check cylinder head Damage scratches Replace 3 Measure cylinder head warpage Out of specification Resurface the cylin der head Maximum cylinder head warpage 0 03 mm 0 0012 in 8 5 7 6 4 3 1 2 1 ...

Page 180: ... ensure an even surface rotate the cylinder head several times EAS00255 CHECKING THE CYLINDER AND PISTON 1 Check piston wall cylinder wall Vertical scratches Rebore or replace the cylinder and replace the piston and piston rings as a set 2 Measure piston to cylinder clearance a Measure cylinder bore C with the cylinder bore gauge NOTE Measure cylinder bore C by taking side to side and front to bac...

Page 181: ... 56 34 56 40 mm 2 218 2 220 in Oversize 56 65 mm 2 23 in Oversize 56 90 mm 2 24 in d If out of specification replace the piston and piston rings as a set e Calculate the piston to cylinder clearance with the following formula Piston to cylinder clearance Cylinder bore C Piston skirt diameter P f If out of specification rebore or replace the cylinder and replace the piston and piston rings as a set...

Page 182: ...ylinder with the piston crown 3 Measure piston ring end gap Out of specification Replace the piston ring NOTE The oil ring expander spacer s end gap cannot be measured If the oil ring rail s gap is exces sive replace all three piston rings Piston ring side clearance Top ring 0 02 0 060 mm 0 0008 0 0024 in 2nd ring 0 035 0 070 mm 0 0014 0 0028 in Piston ring end gap Top ring 0 3 0 45 mm 0 012 0 018...

Page 183: ...e play exists Inspect the connecting rod for wear Replace the pin and or connec ting rod as required 4 Install Piston pin into piston pin hole 5 Check Free play when the piston pin is in place in the piston There should be no noticeable play Free play exists Inspect the connecting rod for wear Replace the pin and or connec ting rod as required 6 Inspect Piston pin and bearing Signs of heat discolo...

Page 184: ...ates 1 Check clutch plate Damage Replace the clutch plates as a set 2 Measure clutch plate warpage with a surface plate and thickness gauge Out of specification Replace the clutch plates as a set EAS00282 CHECKING THE CLUTCH SPRINGS The following procedure applies to all of the clutch springs 1 Check clutch spring Damage Replace the clutch springs as a set Friction plate thickness 2 9 3 1 mm 0 11 ...

Page 185: ...E Pitting on the clutch housing dogs will cause erratic clutch operation 2 Check bearing Damage wear Replace the bearing and clutch housing EAS00285 CHECKING THE CLUTCH BOSS 1 Check clutch boss splines Damage pitting wear Replace the clutch boss NOTE Pitting on the clutch boss splines will cause erratic clutch operation EAS00286 CHECKING THE PRESSURE PLATE 1 Check pressure plate Cracks damage Repl...

Page 186: ...g clutch push rod EAS00292 CHECKING THE PRIMARY DRIVE 1 Check primary drive gear primary driven gear Damage wear Replace the primary drive and primary driven gears as a set Excessive noise during operation Replace the primary drive and primary dri ven gears as a set 2 Check primary drive gear to primary driven gear free play Free play exists Replace the primary drive and primary driven gears as a ...

Page 187: ... flat surface Bends Replace s s WARNING Do not attempt to straighten a bent shift fork guide bar 3 Check shift fork movement along the shift fork guide bar Rough movement Replace the shift forks and shift fork guide bar as a set EAS00422 CHECKING THE SHIFT DRUM ASSEMBLY 1 Check shift drum grooves Damage scratches wear Replace the shift drum assembly shift drum segment Damage wear Replace the shift...

Page 188: ...ission gears Blue discoloration pitting wear Replace the defective gear s transmission gear dogs Cracks damage rounded edges Replace the defective gear s 4 Check transmission gear engagement each pinion gear to its respective wheel gear Incorrect Reassemble the transmis sion axle assemblies 5 Check transmission gear movement Rough movement Replace the defec tive part s 6 Check circlips Bends damag...

Page 189: ...t pawls Return spring Stopper lever Wear damage Replace EAS00394 CHECKING THE CRANKSHAFT AND CONNECTING ROD 1 Measure crankshaft runout Out of specification Replace the crankshaft bearing or both NOTE Turn the crankshaft slowly 2 Measure big end side clearance Out of specification Replace the big end bearing crankshaft pin or connecting rod Maximum crankshaft runout 0 03 mm 0 0012 in 5 2 1 4 3 6 B...

Page 190: ...ction may cause pump output to vary from the factory settings This situation is however extremely dange rous If improper output is suspected inspect the following 1 Inspect Delivery line Obstructions Blow out Pump body seal crankcase cover seal Wear damage Replace 2 Inspect Allowing air Air exists Air bleed Refer to the AUTOLUBE PUMP AIR BLE EDING section in chapter 3 Crankshaft width 57 9 57 95 m...

Page 191: ...age Replace POWER VALVE 1 Eliminate Score marks and lacquer deposits Carbon deposits from power valve specially in cleaning groove surface and its contact surface of cylinder block 2 Check O rings Bushes Gsket seals Wear damage Replace Minimum output 200 stroke 0 38 0 50cm3 0 02 0 03cu in Maximum output 200stroke 4 65 5 15cm3 0 28 0 31cu in 8 5 7 6 4 3 1 2 1 1 1 2 3 1 2 ...

Page 192: ...G THE CRANKCASE 1 Thoroughly wash the crankcase halves in a mild solvent 2 Thoroughly clean all the gasket surfaces and crankcase mating surfaces 3 Check crankcase Cracks damage Replace oil delivery passages Obstruction Blow out with compressed air ...

Page 193: ...NE ASSEMBLY AND ADJUSTMENTS 5 31 AUTOLUBE PUMP 5 Nm 0 5 m kg 3 6ft lb Autolube pump End cap Hose Clip Adjusting bolt Washer Drive shaft Collar O Ring 10 Screw 11 Oil seal 12 Autolube pump gear 13 Pin 14 Circlip ...

Page 194: ...l seal lips 2 Install Drive shaft autolube pump Circlip Pin Drive gear autolube pump Circlip O ring Autolube pump s s WARNING Always use a new circlip Always use a new O ring Lightweight Lithium soap base grease Screw Autolube pump 5 Nm 0 5m kg 3 6ft lb 8 5 7 6 4 3 1 2 1 ...

Page 195: ...VE Power valve Power valve holder right O ring Power valve holder left Gasket seal Pulley housing Pulley Pulley cover Y P V S Cable 7 Nm 0 7 m kg 5 1ft lb 7 Nm 0 7 m kg 5 1ft lb 7 Nm 0 7 m kg 5 1ft lb A USE NEW ONE A USE NEW ONE 10 Nm 1 0 m kg 7 2ft lb ...

Page 196: ...Left and right to cylinder block Bolt Power valve 3 Tighten Bolt Power valve NOTE When tightening the power valve connecting bolt lock the valve by insterting a wooden pice into the exhaust port 4 Install Power valve holder 5 Check Power valve operation Unsmooth operation Repair Molybdenum Disulfide Grease Lightweight Lithium soap base grease Bolt Power Valve 7 Nm 0 7 m kg 5 1 ft lb Bolt Power Val...

Page 197: ...Right 17 Thrust bearing 18 Connecting rod 19 Crank pin 20 Big end bearing 21 Crank Left 22 Wodruff key 23 Bearing 24 Oil seal A PISTON TO CYLINDER CLEARANCE 0 045 0 050 mm 0 0018 0 0020in B EN GAP INSTALLED Top ring 0 30 0 45mm 0 012 0 018in 2rd ring 0 30 0 45mm 0 012 0 018in C CRANKSHAFT Width 57 90 57 95mm 2 279 2 271in Max Runout 0 03mm 0 012in Big end side clearance 0 2 0 7mm 0 0079 0 0276in B...

Page 198: ... washer Circlip Bearing Cylindrical bearing 10 Drive axle 11 1st wheel gear 12 2nd wheel gear 13 3rd wheel gear 14 4th wheel gear 15 5th wheel gear 16 6th wheel gear 19 Special washer 20 Oil seal 21 Drive sprocket 22 Lock washer A RUNOUT LIMIT 008mm 0 003in B USE NEW ONE B USE NEW ONE B USE NEW ONE B USE NEW ONE A RUNOUT LIMIT 0 08mm 0 003in ...

Page 199: ...ENG ENGINE ASSEMBLY AND ADJUSTMENTS 5 37 SHIFTER Shift cam Stopper lever Return spring Securing bolt Shift fork 1 Shift fork 2 Shift fork 3 Shift fork 1 Shift fork 2 14 Nm 1 4 m kg 10ft lb ...

Page 200: ...seal lips with lithium soap based grease and each bearing with engine oil NOTE Hold the connecting rod at top dead center TDC with one hand while turning the nut of the crankshaft installer bolt with the other Turn the crankshaft installer bolt until the crankshaft assembly bottoms against the bearing EAS00427 INSTALLING THE SHIFT FORKS AND SHIFT DRUM ASSEMBLY 1 Install shift fork guide bars shift...

Page 201: ...ng surface of both crankcase hal ves 3 Install Damper collar Dowel pins 4 Install Crankcase Right Installation steps Apply the lithium soap base grease to the oil seal lips Fit the right crankcase onto the left case Tap lightly on the case with a soft hammer NOTE Turn the shift cam to the position shown in the figure so that it doesn t contact the crankcase when installing the crankcase Install th...

Page 202: ...crisscross pattern 5 Apply 2 stroke oil to crank pin bearing and oil delivery hole 6 Check Crankshaft and transmission operation Unsmooth operation Repair REED VALVE 1 Install Breather hose Crankcase Gasket Reed valve assembly Carburetor joint s s WARNING Always use a new gasket A damaged gasket may cause the engine revs to accelerate 2 Tighten Bolts Carburetor joint Bolts Crankcase 8 Nm 0 8 m kg ...

Page 203: ...ENG ENGINE ASSEMBLY AND ADJUSTMENTS 5 41 MAGNETO ROTOR Stator assembly Rotor Washer 80 Nm 8 0 m kg 58ft lb ...

Page 204: ... Rotor NOTE Clean the tapered portions of the cranks haft and rotor When installing the rotor make sure the key is properly seated in the key way of the crankshaft Hold the rotor by the Rotor Holder to tigh ten the nut Screw Stator 8 Nm 0 8 m kg 5 8 ft lb Use Loctite Universal Rotor Holder 90890 01235 Nut Rotor 80 Nm 8 0 m kg 58 ft lb 1 1 1 2 3 4 ...

Page 205: ...ENG ENGINE ASSEMBLY AND ADJUSTMENTS 5 43 SHIFT SHAFT Shift tank Spring Circlip Oil seal Change pedal 15 Nm 1 5 m kg 11ft lb ...

Page 206: ...ith the shift cam 2 Install shift shaft NOTE Lubricate the oil seal lips with lithium soap based grease 3 Check shift pawl position Gaps a and b are not equal Replace the defective part s Shift cam CLUTCH PUSH LEVER 1 Lubricate Bearing Oil seal lip Washer Push lever axle 14Nm 1 4m kg 10 ft lb Lithium Soap Base Grease 4 3 2 1 1 2 1 1 1 a b ...

Page 207: ...ENG ENGINE ASSEMBLY AND ADJUSTMENTS 5 45 2 Install Washer Return spring Push lever 3 Set the return spring to the spring hook 3 1 2 4 ...

Page 208: ...h boss Thrust washer Clutch housing 10 Thrust plate 11 Conical spring washer 12 Push rod 1 13 Ball 14 Push rod 2 15 Push lever axle 16 Return spring 17 Bearing 18 primary drive gear A CLUTCH SPRING FREE LENGHT LIMIT 34 5 mm 1 26in B FRICTION PLATE WEAR LIMIT 2 7 mm 0 106in C CLUTCH PLATE WEAR LIMIT 0 05 mm 0 002in 70 Nm 7 0m kg 50ft lb 80 Nm 8 0 m kg 58ft lb ...

Page 209: ... weight Baffle plate 3 Install Driven gear Balancer weight Straight key CAUTION Align the balancer drive gear mark 3 with the balancer driven gear mark 4 4 Install Lock washer Nut Balancer driven gear Plain washer Nut Primary drive gear NOTE Install the lock washer tab into the key way of the balancer driven gear Oil Seal Retainer 16 Nm 1 6 m kg 11 ft lb Screw Baffle Plate 8 Nm 0 8 m kg 5 8 ft lb ...

Page 210: ...otor to tighten the nut Primary drive gear and nut Balancer driven gear by the Universal Rotor Holder 6 Bend the lock washer tab along the nuts flats 7 Lubricate Push rod 2 Ball Nut Primary drive gear 80 Nm 8 0 m kg 58 ft lb Nut Balancer driven gear 55 Nm 5 5 m kg 40 ft lb Universal Rotor Holder 90890 01235 Lithium Soap Base Grease 8 9 8 7 5 4 3 2 1 3 2 1 ...

Page 211: ...er NOTE Be careful to install the conical spring was her in proper position as shown Install the lock washer tab onto the indentation of the clutch boss 9 Tighten Nut Clutch boss NOTE Hold the clutch boss to tighten the nut clutch boss by the Universal Clutch Holder 10 Bend the lock washer tab along the nut flats Nut Clutch boss 70 Nm 7 0 m kg 50 ft lb Universal Clutch Holder 90890 04086 8 9 8 7 5...

Page 212: ...lates alternately on the clutch boss Be sure to install a clutch plate with pro jection offset aproximately 60º from pre vious plate projection Continue this procedure in a clockwise direction until all clutch plates are installed NOTE Before installing friction and clutch plates sink them into transmission oil almost 3 hours before mounting 12 Install Push rod 1 Pressure plate Clutch springs Bolt...

Page 213: ... Drain plug Transmission oil Drain plug Coolant NOTE Tighten the screws Crankcase cover in stage using a crisscross pattern s s WARNING Always use a new gasket 16 Apply the grease to the O ring 17 Install O ring to water outlet pipe Water outlet pipe s s WARNING Always use a new O ring Screw Crankcase cover 8 Nm 0 8 m kg 5 8 ft lb Drain plug Transmission Oil 15Nm 1 5 m kg 11 ft lb Drain plug Coola...

Page 214: ...linder gasket A SPARK PLUG B MANUFACTURER NGK C TYPE BR9ES D PLUG GAP 0 7 0 8mm 0 028 0 0012in E CYLINDER HEAD WARRAGE LIMIT 0 03mm 0 0012in 13 Nm 1 3m kg 9 4ft lb 20 Nm 2 0m kg 14ft lb 13 Nm 1 3m kg 9 4ft lb 22 Nm 2 2m kg 16ft lb F USE NEW ONE F USE NEW ONE G The UP mark on the gasket musb be facing up 28 Nm 2 8m kg 20ft lb ...

Page 215: ... Before installing the piston pin clip cover the crankcase opening with a clean rag to prevent the clip from falling into the crank case s s WARNING Always use a new piston pin clip CAUTION Do not allow the clip open ends to meet the piston pin slot 2 Check Piston ring position CAUTION Make sure ring ends are properly fitted around ring locating pins in piston groo ves Be sure to check te manufact...

Page 216: ...n rings with the other hand 5 Tighten Nuts cylinder NOTE Tighten the nuts ins stage using a crisscross pattern 6 Install Gasket Cylinder head Cylinder head s s WARNING Always use a new gasket NOTE The UP mark on the gasket must be facing up 7 Tighten Nuts Cylinder head NOTE Tighten the nuts in stage using a crisscross pattern Nut Cylinder 28 Nm 2 8 m kg 20 ft lb Nut Cylinder Head 22 Nm 2 2 m kg 16...

Page 217: ...g Always use a new gasket 9 Install Cover Thermostatic valve 10 Install Spark plug Thermo unit s s WARNING Handle the thermo unit with special care Never subject it too strong or allow it to be dropped In case of being hited replace it Screw Thermostatic Valve Cover 8 Nm 0 8 m kg 5 8 ft lb Spark plug 20 Nm 2 0 m kg 14 ft lb Thermo unit 15 Nm 1 5 m kg 11 ft lb 1 3 2 1 2 1 ...

Page 218: ... Temporary tighten the bolts before tighte ning them to specification 2 Install Spacer collar Drive sprocket Lock washer Nut Drive sprocket Drive chain NOTE Before installing the spacer collar apply grease to the oil seal lip Union bolt 8 Nm 0 8 m kg 5 8 ft lb Pivot shaft 90 Nm 9 0 m kg 65 ft lb Bolt Rear Lower 33 Nm 3 3 m kg 24 ft lb Bolt Front 58 Nm 6 8 m kg 42 ft lb Bolt Engine stay Upper 33 Nm...

Page 219: ...crisscross pattern 5 Adjust Drive chain slack Refer to the DRIVE CHAIN SLACK ADJUSTMENT section in chapter 3 6 Connect Radiator hose Outlet Radiator hose Inlet 7 Install Pulley housing Adjusters Y P V S cables Servomotor unit Screw Crankcase cover 8 Nm 0 8 m kg 5 8 ft lb Bolt Change pedal 15 Nm 1 5 m kg 11 ft lb Bolt Pulley housing 8 Nm 0 8 m kg 5 8 ft lb Screw Servomoto unit 7 Nm 0 7 m kg 5 1 ft ...

Page 220: ...efer to the Y P V S CABLE ADJUST MENT section in chapter 3 NOTE Before adjusting the Y P V S cables turn the main switch ON and operate the Y P V S motor 11 Install Pulley cover Power valve 12 Adjust Clutch cable free play Refer to the CLUTCH ADJUSTMENT section in chapter 3 Bolt Power valve pulley 10Nm 1 0 m kg 7 2 ft lb Bolt Pulley Cover 7 Nm 0 7 m kg 5 1 ft lb 1 1 1 ...

Page 221: ... pipe Exhaust pipe s s WARNING Always use a new gasket 16 Fill Radiator Reservoir tank Radiator Refer to the COOLANT REPLACEMENT section in chapter 3 Bolt Autolube pump cover 5 Nm 0 5 m kg 3 6 ft lb Nut Exhaust pipe 18 Nm 1 8 m kg 13 ft lb Bolt Stay 10 Nm 1 0 m kg 7 2 ft lb Bolt Frame mount 10 Nm 1 0 m kg 7 2 ft lb Screw Muffler joint 10 Nm 1 0 m kg 7 2 ft lb Total amount 0 92L 1 2 3 1 4 ...

Page 222: ...ENG ENGINE ASSEMBLY AND ADJUSTMENTS 5 60 17 Fill Crankcase Refer to the TRANSMISSION OIL REPLA CEMENT section in chapter 3 Total amount 0 92L ...

Page 223: ...COOL ...

Page 224: ...6 ...

Page 225: ...CHAPTER 6 COOLING SYSTEM WATER PUMP 6 1 REMOVAL 6 2 INSPECTION 6 4 INSTALLATION 6 4 THERMOSTATIC VALVE AND RADIATOR 6 7 REMOVAL 6 8 INSPECTION 6 10 INSTALLATION 6 11 COOL ...

Page 226: ... 6 1 COOLING SYSTEM WATER PUMP Impeller shaft Oil Seal Pin Impeller shaft gear Plain washer Circlip Water pump housing cover Gasket Dowel pin 10 Drain bolt 11 Gasket 8 Nm 0 8 m kg 5 8 ft lb A USE NEW ONE A USE NEW ONE ...

Page 227: ...pter 3 Coolant Refer to the COOLANT REPLACEMENT section in chapter 3 2 Disconnect Outlet hose Radiator 3 Remove Screw Water outlet pipe 4 Remove Autolube pump cover 5 Disconnect Oil delivery hose 6 Remove Gasket Autolube pump cover Stopper clip Pump cable Clip Pump cable outer Autolube pump cable NOTE Plug the oil hose so that oil will not run out of the oil tank Turn the pump pulley counterclockw...

Page 228: ...l Crankcase cover 8 Remove Water outlet pipe Housing cover Water pump Gasket Dowel pins 9 Remove Circlip Plain washer Impeller shaft gear 10 Remove Pin Plain washer 11 Remove Impeller shaft 12 Eliminate deposits from the impeller and water pump housing 4 2 3 2 1 1 2 3 1 2 1 1 ...

Page 229: ... the crankcase cover by tapping it towards the outside Install the new oil seal with the WATER SIDE mark on the outside NOTE Apply the lightweight lithium base grease to oil seal outside Press fit the oil seal until it contacts the bot tom INSTALL Reverse the REMOVAL procedure Note the following points 1 Apply Lightweight lithium base grease to oil seal lips and impeller shaft 2 Install Impeller s...

Page 230: ...lithium soap base grease to the brake pedal pivot shaft s s WARNING Always use new cotter pin and gasket 5 Install Screw Water outlet pipe Screw Crankcase cover 8 Nm 0 8 m kg 5 8 ft lb Screw Brake pedal 20 Nm 2 0 m kg 14 ft lb Drain plug Transmission Oil 15 Nm 1 5 m kg 11 ft lb Drain plug Coolant 10 Nm 1 0 m kg 7 2 ft lb Screw Water Outlet pipe 8 Nm 0 8 m kg 5 8 ft lb Screw Crankcase cover 8 Nm 0 ...

Page 231: ...7 Fill Radiator Refer to the COOLANT REPLACEMENT section 8 Air bleeding Autolube pump Refer to the AUTOLUBE PUMP AIR BLEE DING section 9 Install Autolube pump cover Total amount 0 92L Screw Autolube pump cover 5 Nm 0 5 m kg 3 6 ft lb Recommended Oil SAE 10W30 type SE Motor Oil Periodic Oil Change 0 75L ...

Page 232: ...warmer Inlet Thermostatic valve cover 10 Gasket 11 Thermostatic valve 12 O ring 8 Nm 0 8 m kg 5 8 ft lb D USE NEW ONE 8 Nm 0 8 m kg 5 8 ft lb 8 Nm 0 8 m kg 5 8 ft lb 8 Nm 0 8 m kg 5 8 ft lb D USE NEW ONE D USE NEW ONE D USE NEW ONE B COOLANT CAPACITY 0 92L Including all routes C THERMOSTATIC VALVE OPENING TEMPERATURE 63 67 C 146 153 C A RADIATOR CAP OPENING PRESSURE 75 105kPA 0 75 1 05kg cm2 10 14...

Page 233: ...hat coolant doesn t splash painted surfaces If splashes wash it away with water s s WARNING Do not remove the radiator cap drain bolts and hoses specially when the engine and the radiator are hot Scalding hot fluid and steam may be blown out under pressure wich could cause serious injury When the engine has cooled place a thick rag like a towel over the radiator cap slowly rotate the cap countercl...

Page 234: ...C VALVE AND RADIATOR 6 9 4 Remove Radiator cap 5 Disconnect Breather hose Radiator 6 Remove Inlet hose Radiator Outlet hose Radiator 7 Remove Water outlet pipe O ring 8 Remove Radiator fin 9 Remove Radiator 2 1 4 2 1 3 ...

Page 235: ...n Clean Apply compressed air to the rear of the radiator Damage Repair or replace NOTE Straighten any flattened fins with a thin flat head screwdriver 2 Check radiator hoses radiator pipes Cracks damage Replace 3 Measure radiator cap opening pressure Below the specified pressure Replace the radiator cap Radiator cap opening pressure 75 105 kPa 0 75 1 05 kg cm2 10 14 psi 3 ...

Page 236: ...in pressure 4 Inspect Thermostatic valve Valve doesn t open at 63 67ºC 146 153ºF Replace INSTALLATION Reverse the REMOVAL procedure Note the following points 1 Install O ring Thermostatic valve Gasket Thermostatic valve cover s s WARNING Always use new O ring and gasket Screw Thermostatic Valve Cover 8 Nm 0 8 m kg 5 8 ft lb 3 2 1 Radiator cap tester 90890 01325 Radiator cap tester adapter 90890 01...

Page 237: ...ing Water outlet pipe s s WARNING Always use a new O ring 5 Fill Radiator Reservoir tank Radiator Refer to the COOLANT REPLACEMENT section in chapter 3 6 Inspect Cooling system Decrease of pressure leaks Repair as required Screw Water Outlet Pipe 8 Nm 0 8 m kg 5 8 ft lb 2 1 Bolt Radiator 8 Nm 0 8 m kg 5 8 ft lb 1 ...

Page 238: ...STATIC VALVE AND RADIATOR 6 13 Inspection steps Attach the Cooling System Tester to the radiator Apply 100kPa 1 0 kg cm2 14psi pressure Measure the indicated pressure with the gauge Radiator cap tester 90890 01325 ...

Page 239: ...CARB ...

Page 240: ...7 ...

Page 241: ...CARBURETOR CARBURETOR 7 1 REMOVAL 7 2 DISASSEMBLY 7 3 INSPECTION 7 4 ASSEMBLY 7 6 INSTALLATION 7 8 ADJUSTMENT 7 9 REED VALVE 7 10 REMOVAL 7 11 DISASSEMBLY 7 11 INSPECTION 7 12 ASSEMBLY 7 12 INSTALLATION 7 13 CARB ...

Page 242: ...e Needle set Pilot jet Needle jet 10 Gasket 11 Main jet 12 Needle valve assembly 13 Float 14 Drain screw Main Jet M J 210 Main Air Jet M A J ø 0 8 Jet Needle J N 5J40 2 Needle Jet N J Q2 M 939 Pilot Jet P J 17 5 Power Jet PW J 60 Pilot Air Screw P A S Float Height F H 15 5 16 5mm 0 61 0 65in Engine Idling Speed 1250 1450 rev min speed ...

Page 243: ...r Throttle stop screw 1 Remove Side cover Left and Right Seat Radiator cover 2 Turn the fuel cock to OFF position 3 Disconnect Fuel hose from carburetor side 4 Remove Fuel tank s s WARNING Gasoline is highly flammable Avoid spilling fuel over the engine when it s hot 5 Disconnect Reservoir tank Rear brake Y E I S system 1 2 REAR 1 1 ...

Page 244: ...ng hoses 7 Loosen Screw carburetor joint Screw air box 8 Remove Carburetor top Carburetor 9 Remove Cable holder Throttle valve Return spring DISASSEMBLY 1 Remove Hoses 2 Remove Starter plunger assembly 3 Remove Float chamber Gasket float chamber 1 1 1 1 1 2 1 2 1 ...

Page 245: ...tle stop screw Pilot air screw INSPECTION 1 Inspect Carburetor mixing chamber body Contamination Clean NOTE Use petroleum based solvent for cleaning Blow out all passages and jets with compres sed air 2 Inspect Carburetor float chamber body Contamination Clean NOTE Starter jet and all air jets are fixed type 2 1 3 2 1 1 ...

Page 246: ...k Free movement Stick Replace Insert the throttle valve into the carburetor body and check for free movement 6 Inspect Throttle stop screw Pilot air screw O ring Wear Damage Replace 7 Inspect Jet needle Bends Wear Replace 8 Inspect Throttle valve Wear Damage Replace 9 Check Free movement Stick Replace Insert the throttle valve into the carburetor body and check for free movement 1 ...

Page 247: ... Reverse the DISASSEMBLY procedures Note the following points CAUTION Before reassembling wash all parts with clean gasoline 1 Tighten Jet needle holder 2 Install Valve seat Main jet Pilot jet Needle jet NOTE Align the knock pin with the pin slot in the needle jet 3 Measure Float height a Out of specification Adjust Float height F H 15 5 16 5mm 0 61 0 65in 2 4 1 1 ...

Page 248: ...ve but not compressing the needle valve If the float height is not within specification inspect the valve seat and needle valve If either is worn replace them both If both are fine adjust the float height by bending the float tang on the float Recheck the float height 4 Install Float chamber Hose Gasket float chamber s s WARNING Always use a new gasket 5 Tighten Screws Float chamber 6 Install Star...

Page 249: ...rburetor joint with the projection of the carburetor body 2 Adjust Idle speed Refer to the IDLE SPEED ADJUSTMENT section in chapter 3 3 Adjust Carburetor cable free play Refer to the THROTTLE CABLE FREE PLAY ADJUSTMENT section in chapter 3 4 Adjust Carburetor cable free play Refer to the CARBURETOR CABLE FREE PLAY ADJUSTMENT section in chapter 3 Engine idle speed 1250 1450 rev min Throttle cable f...

Page 250: ...e drain pipe Loosen the drain screw and warm up the engine for several minutes Measure the fuel level with tha gauge If the level is incorrect adjust the fuel level Remove the carburetor Inspect the valve seat and needle valve If either is worn replace them both If both are fine adjust the float level by ben ding the float tang slightly Install the carburetor Recheck the fuel level Fuel level 1 5 ...

Page 251: ...CARB REED VALVE 7 10 REED VALVE Reed valve assembly Reed valve Stopper plate Gasket Carburetor joint Y E I S Chamber 10 Nm 1 0 m kg 7 2 ft lb B USE NEW ONE 1 Nm 0 1 m kg 0 7 ft lb ...

Page 252: ...11 REMOVAL 1 Remove Carburetor Refer to the CARBURETOR REMOVAL section 2 Remove Carburetor joint 3 Remove Reed valve assembly Gasket DISASSEMBLY 1 Remove Y E I S chamber 2 Remove Reed valve stopper Reed valve 1 2 1 2 1 1 ...

Page 253: ... stopper height Out of specification Replace Surface plate 4 Inspect Carburetor joint Y E I S chamber Cracks Damage Replace ASSEMBLY Reverse the DISASSEMBLY precedure Note the following points 1 Install Reed valves Reed valve stoppers NOTE Place the reed valve with its concave side facing the reed valve seat Reed valve Bending Limit 0 5mm 0 02in Reed valve Stopper Height 6 8mm 0 27in 2 1 2 1 ...

Page 254: ...ber NOTE The arrow on the Y E I S chamber must point forward INSTALLATION Reverse the REMOVAL procedure Note the following points 1 Install Gasket New Reed valve assembly s s WARNING A damaged gasket may cause the engine revs to accelerate Always use a new gas ket 2 Install Carburetor joint Screws Reed valve 1 Nm 0 1 m kg 0 7 ft lb Use LOCTITE Bolt Carburetor joint 10 Nm 1 0 m kg 7 2 ft lb 1 2 1 1...

Page 255: ...ELEC ...

Page 256: ...8 ...

Page 257: ...UIT OPERATION 8 6 TROUBLESHOOTING 8 8 CHARGING SYSTEM 8 14 CIRCUIT DIAGRAM 8 14 TROUBLESHOOTING 8 15 LIGHTING SYSTEM 8 16 CIRCUIT DIAGRAM 8 16 TROUBLESHOOTING 8 17 SIGNALING SYSTEM 8 26 CIRCUIT DIAGRAM 8 26 TROUBLESHOOTING 8 27 COOLING SYSTEM 8 38 CIRCUIT DIAGRAM 8 38 TROUBLESHOOTING 8 39 YAMAHA POER VALVE SYSTEM 8 42 CIRCUIT DIAGRAM 8 42 TROUBLESHOOTING 8 43 METER ASSEMBLY 8 46 REMOVAL 8 47 INSTA...

Page 258: ...d O Orange L Blue P Pink Y Yellow G Green W White Ch Chocolate Dg Dark green Sb Sky blue Br Brown L Y Blue Yellow B Y Black Yellow B W Black White B R black Red W R White Red W L White Blue Y R Yellow Red G R Green Red G Y Green Yellow G W Green White Br W Brown White L7R Blue Red ...

Page 259: ... 8 2 ELECTRICAL COMPONENTS 1 CDI Unit Servomotor Battery Fuse Neutral switch Thermo unit Rectifier Regulator Ignition coil Main switch Ignition coil Primary coil resistance 0 23 Ω at 20 C Secondary coil resistance 7 9 kΩ at 20 C ...

Page 260: ...ELEC ELECTRICAL COMPONENTS 8 3 ELECTRICAL COMPONENTS 2 Flasher relay Conductor wire Rectifier 2 Oil gauge Sidestand switch Brake switch Relay Horn Battery Capacity 12V 6Ah No maintenance ...

Page 261: ...o the Ωx1 range When checking for continuity switch back and forth between the switch positions a few times The terminal connections for switches e g main switch engine stop switch are shown in an illustration similar to the one on the left The switch positions a are shown in the far left column and the switch lead colors b are shown in the top row in the switch illustration NOTE indicates a conti...

Page 262: ... between the terminals Refer to CHECKING SWITCH CON TINUITY Damage wear Repair or replace Improperly connected Properly connect Incorrect continuity reading Replace the switch 7 20 20 22 23 12 9 10 35 15 28 Main swich 35 Oil Level gauge 24 Left handle swicht 15 Neutral swicht 12 Side stand swicht 28 Rear stop swicht Right handle swicht Fuse ...

Page 263: ...ELEC IGNITION SYSTEM 8 6 IGNITION SYSTEM The circuit diagram showns the ignition system ...

Page 264: ...ELEC IGNITION SYSTEM 8 7 NOTE For the color codes see the electric diagram Magneto CDI Battery Fuse Starter relay Starting engine Main switch C D I Ignition coil 7 5 8 9 4 2 6 1 ...

Page 265: ...k the condition of the spark plug Check the spark plug type Measure the spark plug gap Refer to CHECKING THE SPARK PLUG in chapter 3 Standard spark plug BR8HS NGK Spark plug gap 0 6 0 7 mm Is the spark plug in good condition is it of the correct type and is its gap within spe cification EAS00742 2 Ignition spark gap Disconnect the spark plug cap from the spark plug Connect the ignition checker as ...

Page 266: ...t tester Ω x 1k range to the spark plug cap as shown Measure the spark plug cap resistance Spark plug cap resistance 5KΩ at 20 C 68 C Is the spark plug cap OK EAS00746 4 Ignition coil resistance Orange from the wireharness Disconnect the ignition coil connectors from the ignition coil terminals Connect the pocket tester Ω x 1 to the ignition coil as shown Positive tester probe Orange terminal Nega...

Page 267: ...ondition OFF X X ON X X PARK X X Continuity X No continuity EAS00750 6 ENGINE STOP switch Disconnect the ENGINE STOP switch leads from the wireharness Connect the pocket tester Ω 100 to the ENGINE STOP switch Positive tester probe black white Lead Negative tester probe Black Lead Turn the ENGINE STOP switch to OFF and RUN Check the ENGINE STOP switch for con tinuity Switch Good Bad position condit...

Page 268: ...l resistance Disconnect the CDI magneto coupler from the wire harness Connect the pocket tester Ω 100 to the pickup coil Positive tester probe white blue Negative tester probe white red Measure the pickup coil resistance Pickup coil resistance 280 420 Ω at 20 C 68 F between white red and white blue Is the pickup coil OK EAS00754 9 Wiring Check the entire ignition system s wiring Refer to CIRCUIT D...

Page 269: ...ES NO EAS00751 2 Neutral switch Disconnect the CDI magneto coupler from the wireharness Connect the pocket tester Ω 100 to the neutral switch lead Positive tester probe sky blue lead Negative tester probe Frame ground Shift the transmission in neutral and gear Check the neutral switch for continuity Switch Good Bad position condition condition NEUTRAL X X GEAR X X Continuity X No continuity Is the...

Page 270: ......

Page 271: ...ELEC CHARGING SYSTEM 8 14 EAS00773 CHARGING SYSTEM CIRCUIT DIAGRAM Generator Rectifier regulator Battery Main fuse ...

Page 272: ... Connect the engine tachometer to the spark plug lead Connect the pocket tester DC 20 V to the battery Positive tester probe positive battery terminal Negative tester probe negative battery terminal Start the engine and let it run at approxi mately 3000 r min Measure the charging voltage Charging voltage 14 V at 5000 r min NOTE Make sure the battery is fully charged Is the charging voltage within ...

Page 273: ...ELEC LIGHTING SYSTEM 8 16 EAS00780 LIGHTING SYSTEM CIRCUIT DIAGRAM Magento CDI Rectifier regulator Main switch 21 LIGHTS switch 29 Headlight 34 Tail light 36 Meter lights ...

Page 274: ...t Troubleshoot with the following special tool s Any of the following fail to light head light high beam indicator light taillight auxiliary light or meter light 1 Bulb Remove the bulb Refer to the HEADLIGHT BULB REPLA CEMENT section in the chapter 3 Connect the pocket tester Ω 100 to the bulbs terminals Positive tester probe terminal Negative tester probe terminal Positive tester probe terminal N...

Page 275: ...ocket for continuity Is the bulb socket OK 3 LIGHTS Dimmer switch Connect the pocket tester Ω 100 to the bulbs terminals When turning LIGHTS Dimmer switch to HI Positive tester probe Yellow lead Negative tester probe Black lead When turning LIGHTS Dimmer switch to LO Positive tester probe Green lead Negative tester probe Black lead Turn the LIGHTS Dimmer switch to the HI and LO Check the LIGHTS Di...

Page 276: ...lug lead Start the engine and check the lightning voltage Is the LIGHTS switch OK EAS00787 5 Wiring Check the entire lighting system s wiring Refer to CIRCUIT DIAGRAM Is the lighting system s wiring properly con nected and without defects Replace handlebar switch left YES NO Properly connect or repair the lighting system s wiring Check the condition of each of the ligh ting system s cir cuits Refe...

Page 277: ... Seat 3 Fuel tank 4 Headlight cover 5 Headlight unit Troubleshoot with the following special tool s Meter light does not come on 1 Bulb Remove the bulb Refer to the METER ASSEMBLY section Connect the pocket tester Ω 1 to the bulbs terminals Positive tester probe terminal Negative tester probe terminal Check the bulb for continuity Is the bulb OK Pocket tester 90890 03112 Inductive Tachometer 90890...

Page 278: ...egative tester probe Black Terminal Check the bulb socket for continuity Is the bulb socket OK EAS00787 3 Wiring Check the entire lighting system s wiring Refer to CIRCUIT DIAGRAM Is the lighting system s wiring properly con nected and without defects Replace the bulb socket YES NO Properly connect or repair the lighting system s wiring Check the condition of each of the ligh ting system s cir cui...

Page 279: ... tank 4 Headlight cover 5 Headlight unit Troubleshoot with the following special tool s Tail light Auxiliary light do not come on 1 Bulb Remove the bulb Connect the pocket tester Ω 1 to the bulb terminals Positive tester probe terminal Negative tester probe terminal Positive tester probe terminal Negative tester probe terminal A Tail Brake bulb B Auxiliary light bulb Check the bulb for continuity ...

Page 280: ...ain switch Disconnect the main switch coupler from the wire harness Connect the pocket tester Ω 1 to the main switch Check the main switch for continuity A Positive tester probe Red Lead Negative tester probe Brown blue Lead Switch Good Bad position condition condition ON X X OFF X X B Positive tester probe Yellow blue Lead Negative tester probe Blue Black Lead Switch Good Bad position condition c...

Page 281: ...em s wiring Refer to CIRCUIT DIAGRAM Is the lighting system s wiring properly con nected and without defects Properly connect or repair the lighting system s wiring Check the condition of each of the ligh ting system s cir cuits Refer to CHEC KING THE LIGH TING SYSTEM YES NO ...

Page 282: ......

Page 283: ...G SYSTEM CIRCUIT DIAGRAM Main switch Main fuse Battery 15 Neutral switch 35 Engine oil level switch 37 Diode 20 Horn switch 25 Horn 22 Turn switch 26 Turn signal relay 34 Tail brake light 28 Rear brake light switch 27 Front brake light switch ...

Page 284: ...ke light or an indicator light do not come on and the horn fails to sound 3 Main switch Disconnect the main switch coupler from the wire harness Connect the pocket tester Ω 1 to the main switch Tester Lead Red Lead Teter Lead Brown Blue Lead Turn the main switch to ON OFF and PARK Check the main switch for continuity Switch Good Bad position condition condition ON X X OFF X X PARK X X Continuity X...

Page 285: ...sockets Disconnect the flahser light leads from the wire harness Connect the pocket tester Ω 1 to the flas her light leads When checking right flasher light Positive tester probe Dark Green Lead Negative tester probe Black Lead When checking left flasher light Positive tester probe Chocolate Lead Negative tester probe Black Lead Check the bulb socket for continuity Is the bulb socket OK Replace th...

Page 286: ...the TURN switch OK 4 Voltage Disconnect the flasher relay coupler from the wire harness Turn the main switch to ON Turn the TURN switch to the R or L Connect the pocket tester DC20V to the flasher relay coupler Positive tester probe Brown Terminal Negative tester probe Frame ground Check the flasher votage Flasher voltage 12 0 V Is the flasher relay OK EAS00795 5 Wiring Check the entire signal sys...

Page 287: ...lb for continuity Is the bulb OK BRAKE LIGH DOES NOT COME ON 2 Bulb socket Disconnect the bulb socket coupler from the wire harness Connect the pocket tester Ω 1 to the bulb socket leads Positive tester probe Yellow Terminal Negative tester probe Black Terminal Check the bulb socket for continuity Is the bulb socket OK Replace the bulb YES NO Replace the bulb socket YES NO ...

Page 288: ... Connect the pocket tester Ω 1 to the brake switch coupler Positive tester probe Brown Terminal Negative tester probe Green Yellow Terminal Check the brake switch for continuity Switch Good Bad position condition condition Rear brake X X applied Rear brake X X not applied Continuity X No continuity Is the rear brake switch OK EAS00795 5 Wiring Check the entire signal system s wiring Refer to CIRCU...

Page 289: ...eck the bulb for continuity Is the bulb OK NEUTRAL INDICATOR LIGHT DOES NOT COME ON 2 Bulb socket Disconnect the bulb socket coupler from the wire harness Connect the pocket tester Ω 1 to the bulb socket leads Positive tester probe Brown Terminal Negative tester probe Sky Blue Terminal Check the bulb socket for continuity Is the bulb socket OK Replace the bulb YES NO Replace the bulb socket YES NO...

Page 290: ... switch for continuity Switch Good Bad position condition condition Neutral X X Gear X X Continuity X No continuity Is the neutral switch OK EAS00795 4 Wiring Check the entire signal system s wiring Refer to CIRCUIT DIAGRAM Is the signaling system s wiring properly connected and without defects Replace the neutral switch YES NO Properly connect or repair the signaling system s wiring Check the con...

Page 291: ...nal Check the bulb for continuity Is the bulb OK OIL INDICATOR LIGHT DOES NOT COME ON 2 Bulb socket Disconnect the bulb socket coupler from the wire harness Connect the pocket tester Ω 1 to the cou pler Positive tester probe Brown Terminal Negative tester probe Black Red Terminal Check the bulb socket for continuity Is the bulb socket OK Replace the bulb YES NO Replace the bulb socket YES NO ...

Page 292: ...r probe Black Terminal Hold the oil level switch in an upright and upside down position Check the oil level switch for continuity Switch Good Bad position condition condition Upright X X Upside X X Continuity X No continuity Is the oil level switch OK EAS00795 5 Wiring Check the entire signal system s wiring Refer to CIRCUIT DIAGRAM Is the signaling system s wiring properly connected and without d...

Page 293: ... level switch OK HORN DOES NOT SOUND WHEN PUS HING HORN SWITCH 2 Voltage Connect the pocket tester DC20V to the horn terminal Positive tester probe Brown Terminal Negative tester probe Frame ground Turn the main switch to ON Check the horn voltage Horn voltage 12 0 V EAS00795 3 Wiring Check the entire signal system s wiring Refer to CIRCUIT DIAGRAM Is the signaling system s wiring properly connect...

Page 294: ...o the horn ter minal and ground the jumper lead Does the horn sounds OK 5 Voltage Connect the pocket tester DC20V to the horn at the pink terminal Positive tester probe Pink Terminal Negative tester probe Frame ground Check the pink terminal voltage Pink terminal voltage 12 0 V Replace the horn YES NO ...

Page 295: ...ELEC COOLING SYSTEM 8 38 EAS00807 COOLING SYSTEM CIRCUIT DIAGRAM Battery Main switch Main fuse 13 Thermo switch ...

Page 296: ...uel tank 4 headlight cover 5 headlight unit Troubleshoot with the following special tool s The radiator fan motor fails to turn The water temperature gauge needle fails to move when the engine is warm 1 Fuse Remove the fuse Connect the pocket tester Ω 1 to the fuse Check the fuse for continuity Is the fuse OK 2 Battery Check the battery condition Refer to the BATTERY INSPECTION sec tion in chapter...

Page 297: ...tion ON X X OFF X X PARK X X Continuity X No continuity 4 Thermo unit Remove the thermo unit from the cylinder head Connect the pocket tester Ω 1 to the ther mo unit Inmerse the thermo unit in the water Measure the resistances Note temperatures while heating the water with the temperature gauge Positive tester probe Terminal Negative tester probe Body ground Water 50ºC 80ºC 100ºC temperature 122ºF...

Page 298: ...s wiring Refer to CIRCUIT DIAGRAM Is the signaling system s wiring properly connected and without defects Properly connect or repair the signaling system s wiring Check the condition of each of the sig naling system s cir cuits Refer to CHEC KING THE SIGNA LING SYSTEM YES NO ...

Page 299: ...ELEC YAMAHA POWER VALVE SYSTEM 8 42 YAMAHA POWER VALVE SYSTEM CIRCUIT DIAGRAM 16 CDI Unit Main switch Main fuse Battery 18 Servomotor ...

Page 300: ...lo wing part s 1 side covers left and right 2 seat 3 fuel tank 4 headlight cover 5 headlight unit Troubleshoot with the following special tool s Servomotor does not move 1 Fuse Remove the fuse Connect the pocket tester Ω 1 to the fuse Check the fuse for continuity Is the fuse OK 2 Battery Check the battery condition Refer to the BATTERY INSPECTION sec tion in chapter 3 Pocket tester 90890 03112 Re...

Page 301: ...connect servomotor coupler from the wire harness Connect the battery leads to the servomo tor Positive tester probe Brown Terminal Negative tester probe Black Terminal Check the servomotor for operation Is the servomotor OK EAS00795 5 Wiring Check the entire signal system s wiring Refer to CIRCUIT DIAGRAM Is the signaling system s wiring properly connected and without defects Replace the main swit...

Page 302: ...ervomotor and tachometer operation Start the engine and increase revolution to about 7000rev min Check servomotor and tachometer for operation Pocket tester 90890 03112 Is the servomotor OK Replace the servo motor YES NO ...

Page 303: ...ELEC METER ASSEMBLY 8 46 METER ASSEMBLY Speedometer Bulb Bulb socket Speedometer cable Meter cushion Meter bracket Stopper clip Washer Damper collar ...

Page 304: ...EC METER ASSEMBLY 8 47 REMOVAL 1 Remove Headlight cover 2 Disconnect Headlight leads Auxiliary light leads 3 Remove Band 4 Disconnect Speedometer cable 5 Disconnect Meter leads 6 Remove Meter assembly 1 1 ...

Page 305: ...ulling the leads INSTALLATION Reverse the REMOVAL procedure Note the following points 1 Install the meter lights indicator lights and leads as shown OIL indicator light NEUTRAL indicator light HIGH BEAM indicator light TURN indicator light 2 Install Meter assembly Bolt Meter Assembly 7 Nm 0 7 m kg 5 1 ft lb 3 2 4 1 3 1 2 ...

Page 306: ...nstall the headlight lens unit onto the head light stay by fitting the guide rubber pro perly in the guide hole of the headlight unit 3 Install Headlight cover 4 Adjust Headlight beam Refer to the HEADLIGHT BEAM ADJUST MENT section 1 ...

Page 307: ...TRBL SHTG ...

Page 308: ...9 ...

Page 309: ...LUTCH SLIPPING DRAGGING 9 5 CLUTCH SLIPPING 9 5 CLUTCH DRAGGING 9 6 FAULTY BRAKE 9 6 POOR BRAKING EFFECT 9 6 FRONT FORK OIL LEAKAGE AND FRONT FORK MALFUNCTION 9 6 OIL LEAKAGE 9 6 MALFUNCTION 9 6 INSTABLE HANDLING 9 7 INSTABLE HANDLING 9 7 FAULTY SIGNAL AND LIGHTING SYSTEM 9 8 HEADLIGHT DARK 9 8 BULB BURNT OUT 9 8 FLASHER DOES NOT LIGHT 9 8 FLASHER KEEPS ON 9 8 FLASHER WINKS SLOWER 9 8 FLASHER WINK...

Page 310: ...ogged fuel filter Clogged fuel tank cap Deteriorated fuel or fuel containing or foreign material Fuel cock Clogged fuel hose Carburetor Deteriorated fuel fuel containing water or foreign material Clogged pilot jet Clogged pilot air passage Sucked in air Deformed float Groove worm needle valve Improperly sealed valve seat Improperly adjustment fuel level Improperly set pilot jet Clogged starter jet...

Page 311: ...lty sidestand switch Faulty ignition control unit COMPRESSION SYSTEM PROBABLE CAUSE Cylinder and cylinder head Loose spark plug Loose cylinder head or cylinder Broken cylinder head gasket Broken cylinder gasket Worn damaged or seized cylinder Piston and piston rings Improperly installed piston ring Worn fatigued or broken piston ring Seized piston ring Seized or damaged piston Crankcase and cranks...

Page 312: ...erial Clogged fuel breather hose Fuel cock Clogged fuel hose Carburetor Deteriorated fuel or fuel containing water or foreign material Sucked in air Deformed float Groove worn needle valve Improperly sealed valve seat Improperly set clip position of jet needle Improperly adjusted fuel level Clogged or loose main jet Clogged or loose needle jet Air cleaner Clogged air filter ELECTRICAL SYSTEM PROBL...

Page 313: ...se Improperly sealed crankcase Damaged oil seal Seized crankshaft Reed valve Deformed reed valve stopper Improperly adjusted reed valve stopper height Improperly seated reed valve Loose intake manifold Broken gasket Broken reed valve Y P V S PROBABLE CAUSE Power valve Seized or damaged power valve Carbon buid up Control cable Improperly adjustable cable Seized or discontinuous cable Electrical par...

Page 314: ...ties Seized shift fork Bent shift forks guide bar Transmission Seized transmission gear Jammed impurities Incorrectly assembled transmission JUMP OUT GEAR PROBABLE CAUSE Shift shaft Improperly adjusted shift lever position Improperly returned stopper lever Shift fork Worn shift fork Shift cam Improper thrust play Worn shift cam groove Transmission Worn gear dog CLUTCH SLIPPING DRAGGING CLUTCH SLIP...

Page 315: ...y cylinder kit cup Faulty caliper kit seal Loose union bolt Broken brake hose Oily or grasy brake disc Oily or greasy brake pad Improper brake fluid level FRONT FORK OIL LEAKAGE AND FRONT FORK MALFUNCTION OIL LEAKAGE PROBABLE CAUSE Bent damaged or rusty inner tube Damaged or cracked outer tube Damaged oil seal lip Improperly installed oil seal Improper oil level too much Loose damper rod holding b...

Page 316: ...n Uneven damping adjuster position Broken spring Twisted front forks Tires Uneven tire pressure on both sides Incorrect tire pressure Unevenly worn tires Wheels Incorrect wheel balance Deformed cast wheel Loose bearing Bent or loose wheel axle Excessive wheel run out Frame Twisted Damaged head pipe Improperly installed bearing race Swingarm Worn bearing or bush Bent or damaged Rear shock absorber ...

Page 317: ...BABLE CAUSE Improperly grounded Discharged battery Faulty TURN switch Faulty flasher relay Broken wireharness Loosely connected coupler Bulb burnt out FLASHER KEEPS ON PROBABLE CAUSE Faulty flasher relay Insufficient battery capacity nearly discharged Bulb burnt out FLASHER WINKS SLOWER PROBABLE CAUSE Faulty flasher relay Insufficient battery capacity nearly discharged Improper bulb Faulty main an...

Page 318: ...at range Faulty CDI unit Fuel system Improper carburator main jet improper setting Improperly adjusted fuel heigh Clogged air cleaner element Lean mixture Faulty Autolube pump settings Compression system Heavy carbon build up Transmission oil Incorrect oil level Improper oil viscosity Inferior oil quality Brake Dragging bike Cooling system Faulty water temperature gauge Faulty thermo unit Incorrec...

Page 319: ...DT125 WIRING DIAGRAM ...

Page 320: ... Fr Stop Sw 28 Rr Stop Sw 29 Head Light 30 Fr Lh Flasher 31 Rr Lh Flasher 32 Fr Rh Flasher 33 Rr Rh Flasher 34 Tail Stop Light 35 Oil Level Gauge 36 Meter 37 Diode 1 38 License Light 39 Position Lamp 40 Anti Theft Unit COLOR CODE B Balck R Red L Blue G Green Or Orange Y Yellow P Pink Br Brown Ch Chocolate Sb Skip blue Dg Dark green W White Gy Gray BG Black Green BY Black Yellow BW Black White GR G...

Reviews: