Yamaha YZ125X 2021 Owner'S Service Manual Download Page 219

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CARBURETOR

7-4

Disassembling the carburetor

Order

Job/Parts to remove

Q’ty

Remarks

Mixing chamber top

Throttle valve

Needle holder

Jet needle

Float chamber

Needle jet cover

Float pin

Float

Valve seat

Main jet

Main jet holder

Pilot jet

Starter plunger

Throttle stop screw

Pilot air screw

4.0 N

・

m (0.40 k

・

.0 lb

・

ft)

Summary of Contents for YZ125X 2021

Page 1: ...Read this manual carefully before operating this vehicle 2021 OWNER S SERVICE MANUAL YZ125X YZ125XM LIT 11626 34 08 B1B 2819U 10 ...

Page 2: ... cause cancer and birth defects or other reproductive harm To minimize exposure avoid breathing exhaust do not idle the engine except as necessary service your vehicle in a well ventilated area and wear gloves or wash your hands frequently when servicing your vehicle For more information go to www P65Warnings ca gov passenger vehicle Read this manual carefully before operating this vehicle This ma...

Page 3: ...ANUAL 2021 by Yamaha Motor Corporation U S A First edition March 2020 All rights reserved Any reproduction or unauthorized use without the written permission of Yamaha Motor Corporation U S A is expressly prohibited P N LIT 11626 34 08 ...

Page 4: ...quested not to undertake inspection adjustment disassem bly or reassembly only by reference to this manual It may lead to servicing trouble and mechanical damage WARNING EWA20270 PLEASE READ THIS MANUAL CAREFULLY AND COMPLETELY BEFORE OPERATING THIS MACHINE DO NOT ATTEMPT TO OPERATE THIS MACHINE UNTIL YOU HAVE ATTAINED A SATISFACTORY KNOWLEDGE OF ITS CONTROLS AND OPERATING FEATURES AND UNTIL YOU H...

Page 5: ...EAM20162 YAMAHA MOTOR CORPORATION U S A YZ MOTORCYCLE LIMITED WARRANTY ...

Page 6: ...steps there are exploded diagrams 3 at the start of each removal and disassembly section Numbers 4 are given in the order of the jobs in the exploded diagram A number indicates a removal or a disassembly step Symbols 5 indicate parts to be lubricated or replaced Refer to SYMBOLS A job instruction chart 6 accompanies the exploded diagram providing the order of jobs the names of parts the notes in j...

Page 7: ...ITION Serviceable with engine mounted Gear oil Filling fluid Molybdenum disulfide oil Lubricant Brake fluid Special tool Wheel bearing grease Tightening torque Lithium soap based grease Wear limit clearance Molybdenum disulfide grease Engine speed Silicone grease Electrical data Apply locking agent LOCTITE Engine oil Replace the part with a new one G M BF B T R LS M S LT E New ...

Page 8: ......

Page 9: ...GENERAL INFORMATION 1 SPECIFICATIONS 2 PERIODIC CHECKS AND ADJUSTMENTS 3 CHASSIS 4 ENGINE 5 COOLING SYSTEM 6 FUEL SYSTEM 7 ELECTRICAL SYSTEM 8 TROUBLESHOOTING 9 TUNING 10 EAM10003 TABLE OF CONTENTS ...

Page 10: ......

Page 11: ...D DISASSEMBLY 1 8 REPLACEMENT PARTS 1 8 GASKETS OIL SEALS AND O RINGS 1 8 LOCK WASHERS PLATES AND COTTER PINS 1 9 BEARINGS AND OIL SEALS 1 9 CIRCLIPS 1 9 BASIC SERVICE INFORMATION 1 10 ELECTRICAL SYSTEM 1 10 SPECIAL TOOLS 1 12 INSTRUMENT AND CONTROL FUNCTIONS 1 16 ENGINE STOP SWITCH 1 16 SHIFT PEDAL 1 16 KICKSTARTER LEVER 1 16 FRONT BRAKE LEVER 1 16 REAR BRAKE PEDAL 1 16 FUEL COCK 1 16 STARTER KNO...

Page 12: ...MAINTENANCE AFTER BREAK IN 1 20 MAJOR MAINTENANCE 1 20 AIR FILTER MAINTENANCE 1 20 TORQUE CHECK POINTS 1 21 MOTORCYCLE CARE AND STORAGE 1 23 CARE 1 23 STORAGE 1 24 ...

Page 13: ...re riding 2 This motorcycle is designed to carry the oper ator only No passengers 3 The failure of motorists to detect and recog nize motorcycles in traffic is the predominat ing cause of automobile motorcycle accidents Many accidents have been caused by an automobile driver who did not see the motorcycle Making yourself conspic uous appears to be very effective in reducing the chance of this type...

Page 14: ... Many companies with no connection to Yamaha manufacture parts and accessories or offer oth er modifications for Yamaha vehicles Yamaha is not in a position to test the products that these aftermarket companies produce Therefore Yamaha can neither endorse nor recommend the use of accessories not sold by Yamaha or modifications not specifically recommended by Yamaha even if sold and installed by a ...

Page 15: ...he fuel cock if equipped is in the OFF position and that there are no fuel leaks 3 Point the front wheel straight ahead on the trailer or in the truck bed and choke it in a rail to prevent movement 4 Shift the transmission in gear for models with a manual transmission 5 Secure the motorcycle with tie downs or suit able straps that are attached to solid parts of the motorcycle such as the frame or ...

Page 16: ...LOCATION OF IMPORTANT LABELS 1 4 EAM20085 LOCATION OF IMPORTANT LABELS Please read the following important labels carefully before operating this vehicle 3 4 2 5 1 ...

Page 17: ...for the vehicle you have purchased 12 7 8 1 3 9 11 10 19 13 14 15 18 16 17 2 4 6 5 1 Clutch lever 2 Engine stop switch 3 Front brake lever 4 Throttle grip 5 Radiator cap 6 Fuel tank cap 7 Kickstarter lever 8 Fuel tank 9 Radiator 10 Coolant drain bolt 11 Check bolt Transmission oil level 12 Rear brake pedal 13 Valve joint 14 Fuel cock 15 Air filter 16 Drive chain 17 Shift pedal 18 Starter knob 19 F...

Page 18: ...or positive identi fication of the model you own 2 If your vehicle is stolen the authorities will need the number to search for and identify your vehicle EAM30002 VEHICLE IDENTIFICATION NUMBER The vehicle identification number 1 is stamped into the right side of the frame EAM30003 ENGINE SERIAL NUMBER The engine serial number 1 is stamped into the elevated part of the right side of the engine ...

Page 19: ...owing out and is installed to the fuel tank breather hose NOTICE ECA27110 In this installation make sure the arrow fac es the fuel tank and also downward EAM30615 COLLAR tool for YPVS This collar 1 is used to remove and install the push rod of the engine NOTICE ECA27100 Be sure to use the collar If the collar is not used the power valve constituent parts will result in damage ...

Page 20: ...red to the chassis paint and plating will be damaged Therefore rinse it out with water in good time WARNING EWA18970 Coolant is potentially harmful and should be handled with special care If it enters your eyes wash it away with wa ter enough and then get medical attention If it splashes on your skin or clothes quick ly wash it away with water and then with soapy water If it is swallowed immediate...

Page 21: ...oil seal make sure that its main lip faces the oil chamber the target to be sealed Before installation always apply a light coat of grease to the oil seal lip NOTICE ECA13300 Do not spin the bearing with compressed air because this will damage the bearing surfac es EAM30014 CIRCLIPS When assembling parts always use new cir clips During installation of a circlip make sure that the edge 2 of the cir...

Page 22: ...est har ness Checking the connections Check the leads couplers and connectors for stains rust moisture etc 1 Disconnect Lead Coupler Connector NOTICE ECA16780 When disconnecting a coupler release the coupler lock hold both sections of the cou pler securely and then disconnect the cou pler There are many types of coupler locks therefore be sure to check the type of cou pler lock before disconnectin...

Page 23: ...nector TIP When connecting a coupler or connector make sure that both terminals are connected securely Make sure all connections are tight 5 Check No continuity TIP If there is no continuity clean the terminals When checking the wire harness perform steps 1 to 4 As a quick remedy use a contact revitalizer available at most part stores 1 Digital circuit tester CD732 90890 03243 Model 88 Multimeter ...

Page 24: ...th YM YU or ACC For others use tool number starting with 90890 Tool name Tool No Illustration Reference pages Digital circuit tester CD732 90890 03243 Model 88 Multimeter with tachometer YU A1927 1 11 8 5 8 6 8 6 8 7 8 7 8 7 8 8 Steering nut wrench 90890 01403 Exhaust flange nut wrench YU A9472 3 18 4 51 Spoke nipple wrench 6 7 90890 01521 Spoke nipple wrench 6 7 YM 01521 3 24 Dial gauge stand set...

Page 25: ...1235 Universal magneto and rotor holder YU 01235 5 16 5 17 Flywheel puller 90890 01189 Flywheel puller YM 01189 5 16 Universal clutch holder 90890 04086 Universal clutch holder YM 91042 5 28 5 30 Thickness gauge 90890 03268 Feeler gauge set YU 26900 9 5 28 Tool name Tool No Illustration Reference pages YU 01304 ...

Page 26: ... 85505 Three bond No 1215 5 38 Crankshaft installer pot 90890 01274 Installing pot YU 90058 5 38 5 41 Crankshaft installer bolt 90890 01275 Bolt YU 90060 5 38 5 41 Adapter M8 90890 01499 Adapter M8 YM 01499 5 38 Adapter M12 90890 01278 Adapter 3 YU 90063 5 41 Tool name Tool No Illustration Reference pages YU 90058 YU 90059 ...

Page 27: ...r 90890 01352 Pressure tester adapter YU 33984 6 3 6 3 Fuel level gauge adapter 90890 01470 Fuel level gauge adapter YM 01470 7 10 Fuel level gauge 90890 01312 Fuel level gauge YM 01312 A 7 10 Ignition checker 90890 06754 Oppama pet 4000 spark checker YM 34487 8 6 Tool name Tool No Illustration Reference pages YU 24460 A YU 33984 ...

Page 28: ...has a primary kickstarter lever so the engine can be started in any gear if the clutch is disengaged In normal practices however shift to neutral be fore starting EAM30188 FRONT BRAKE LEVER The front brake lever 1 is located on the right handlebar Pull it toward the handlebar to acti vate the front brake EAM30189 REAR BRAKE PEDAL The rear brake pedal 1 is in the right of the chassis Press down on ...

Page 29: ...ible EAM30444 STARTER KNOB CHOKE When cold the engine requires a richer air fuel mixture for starting A separate starter circuit which is controlled by the starter knob 1 sup plies this mixture Pull the starter knob out to open the circuit for starting When the engine has warmed up push it in to close the circuit EAM30190 SIDESTAND This sidestand 1 is used to support only the machine when standing...

Page 30: ...push the engine stop switch TIP Continue pushing the engine stop switch till the engine comes to a full stop EAM30197 STARTING A WARM ENGINE Do not operate the starter knob CHOKE Open the throttle slightly and start the engine by kick ing the kickstarter forcefully with firm stroke EAM30198 BREAK IN PROCEDURES A break in is important so that rotating portion sliding surfaces and mounted areas may ...

Page 31: ...lowing parts are replaced a break in is required Cylinder and Crankshaft A break in is re quired for about an hour Piston Piston ring Valve Camshaft and Gear A break in is required for about 30 minutes at a throttle opening of 1 2 or less Observe the condition of the engine carefully during a break in For checkpoints for a break in see MAIN TENANCE AFTER BREAK IN If any prob lem is found immediate...

Page 32: ... nuts Check for looseness in mounted areas of parts as well as engine mounting bolts and engine brackets 2 For the chassis Check welds and mounted areas of the frame the swingarm the link the bracket and so on for looseness and cracks Wheel s Check the wheel for runout Check the spoke for looseness Brake s Check the brake disc mounting bolt for loose ness Check that the reservoir contains the spec...

Page 33: ...k to swingarm Mounting of rear shock absorber Rear shock absorber and frame Mounting of swingarm Tightening of pivot shaft Wheel s Mounting of wheel Front Tightening of wheel axle Tightening of axle holder Tightening of spoke nipple Rear Tightening of wheel axle Wheel to rear wheel sprocket Tightening of spoke nipple Brake s Front Brake caliper to front fork Brake disc to wheel Tightening of union...

Page 34: ...UES on page 2 9 Plastic cover Tightening of front fender Tightening of fork leg protector Tightening of air scoop Left cover to rear frame Tightening of side cover Tightening of rear fender Tightening of mud flap Tightening of rear brake disc cover Tightening of rear brake caliper cover ...

Page 35: ...nstructed Also thorough ly rinse the area off with water immediately dry it and then apply a corrosion protec tion spray Improper cleaning can damage plastic parts such as cowlings panels wind shields headlight lenses meter lenses etc and the mufflers Use only a soft clean cloth or sponge with water to clean plastic However if the plastic parts cannot be thor oughly cleaned with water diluted mild...

Page 36: ...and nickel plated sur faces 5 Use spray oil as a universal cleaner to re move any remaining dirt 6 Touch up minor paint damage caused by stones etc 7 Wax all painted surfaces 8 Let the motorcycle dry completely before storing or covering it WARNING EWA19050 Contaminants on the brakes or tires can cause loss of control Make sure that there is no oil or wax on the brakes or tires If necessary clean ...

Page 37: ...ith the engine stop switch pushed in kick the engine over several times to coat the cylinder walls with oil 4 Lubricate all control cables and the pivoting points of all levers and pedals as well as of the sidestand 5 Check and if necessary correct the tire air pressure and then lift the motorcycle so that both of its wheels are off the ground Alterna tively turn the wheels a little every month in...

Page 38: ...MOTORCYCLE CARE AND STORAGE 1 26 ...

Page 39: ...CATIONS 2 1 ENGINE SPECIFICATIONS 2 2 CHASSIS SPECIFICATIONS 2 5 ELECTRICAL SPECIFICATIONS 2 8 TIGHTENING TORQUES 2 9 GENERAL TIGHTENING TORQUE SPECIFICATIONS 2 9 ENGINE TIGHTENING TORQUES 2 10 CHASSIS TIGHTENING TORQUES 2 11 CABLE ROUTING DIAGRAM 2 15 ...

Page 40: ...Model Model B1B8 Dimensions Overall length 2140 mm 84 3 in Overall width 825 mm 32 5 in Overall height 1285 mm 50 6 in Seat height 955 mm 37 6 in Wheelbase 1455 mm 57 3 in Ground clearance 350 mm 13 78 in Weight Curb weight 95 kg 209 lb Riding capacity 1 person ...

Page 41: ...p qt Quantity 0 66 L 0 70 US qt 0 58 Imp qt Cooling system Coolant quantity Radiator including all routes 0 90 L 0 95 US qt 0 79 Imp qt Radiator cap valve opening pressure 93 3 122 7 kPa 0 93 1 23 kgf cm 13 5 17 8 psi Spark plug s Manufacturer model NGK BR9EVX Spark plug gap 0 6 0 7 mm 0 024 0 028 in Cylinder head Warpage limit 0 03 mm 0 0012 in Cylinder Bore 54 000 54 014 mm 2 1260 2 1265 in Wear...

Page 42: ...ary reduction ratio 3 368 64 19 Transmission type Constant mesh 6 speed Gear ratio 1st 2 385 31 13 2nd 1 933 29 15 3rd 1 588 27 17 4th 1 353 23 17 5th 1 200 24 20 6th 1 095 23 21 Main axle runout limit 0 01 mm 0 0004 in Drive axle runout limit 0 01 mm 0 0004 in Secondary reduction ratio 3 846 50 13 Final drive Chain Air filter Air filter element Wet element Air filter oil grade Yamaha foam air fil...

Page 43: ...ENGINE SPECIFICATIONS 2 4 Reed valve Thickness 0 470 mm 0 0185 in Valve stopper height 8 2 8 6 mm 0 32 0 34 in Valve bending limit 0 2 mm 0 01 in ...

Page 44: ...del DUNLOP AT81 Tire air pressure measured on cold tires Front 100 kPa 1 00 kgf cm 15 psi Rear 100 kPa 1 00 kgf cm 15 psi Front brake Type Hydraulic single disc brake Brake disc thickness limit 2 5 mm 0 10 in Brake disc runout limit as measured on wheel 0 15 mm 0 0059 in Brake pad lining thickness limit 1 0 mm 0 04 in Master cylinder inside diameter 9 52 mm 0 37 in Caliper cylinder inside diameter...

Page 45: ...adjustable type Unit for compression damping adjustment Click Adjustment value from the start position Soft 20 Adjustment value from the start position STD 15 Adjustment value from the start position Hard 0 Rear suspension Type Swingarm link suspension Spring Coil spring Shock absorber Gas hydraulic damper Wheel travel 315 mm 12 4 in Spring preload Adjusting system Mechanical adjustable type Adjus...

Page 46: ... Hard 0 Slow compression damping Unit for adjustment Click Adjustment value from the start position Soft 20 Adjustment value from the start position STD 13 Adjustment value from the start position Hard 0 Drive chain Size 520 Chain type Sealed type Number of links 114 Drive chain slack Maintenance stand 48 0 58 0 mm 1 89 2 28 in 15 link length limit 239 3 mm 9 42 in ...

Page 47: ...on timing B T D C 0 50 mm 0 02 in Pickup coil resistance 248 0 372 0 Charging coil 1 resistance 720 0 1080 0 Charging coil 2 resistance 44 0 66 0 Ignition coil Primary coil resistance 0 24 0 36 Secondary coil resistance 5 68 8 52 k Spark plug cap Resistance 5 00 k Charging system Charging system CDI magneto ...

Page 48: ...To avoid warpage tight en multi fastener assemblies in a crisscross pat tern and progressive stages until the specified tightening torque is reached Unless otherwise specified tightening torque specifications re quire clean dry threads Components should be at room temperature A Distance between flats B Outside thread diameter A nut B bolt General tightening torques N m kgf m lb ft 10 mm 6 mm 6 0 6...

Page 49: ... 4 lb ft Coolant drain bolt M6 1 10 N m 1 0 kgf m 7 4 lb ft Radiator bolt M6 6 10 N m 1 0 kgf m 7 4 lb ft Radiator guard bolt M6 2 10 N m 1 0 kgf m 7 4 lb ft Radiator hose clamp M6 8 1 5 N m 0 15 kgf m 1 1 lb ft Air filter element M6 1 2 0 N m 0 20 kgf m 1 5 lb ft Carburetor joint bolt M6 4 10 N m 1 0 kgf m 7 4 lb ft Carburetor joint clamp M4 1 2 3 N m 0 23 kgf m 1 7 lb ft Air filter case joint cl...

Page 50: ... 7 4 lb ft Stopper lever bolt M6 1 10 N m 1 0 kgf m 7 4 lb ft Segment M8 1 30 N m 3 0 kgf m 22 lb ft Exhaust pipe bolt M6 2 12 N m 1 2 kgf m 8 9 lb ft Exhaust pipe stay bolt front M6 1 12 N m 1 2 kgf m 8 9 lb ft Exhaust pipe stay bolt rear M6 1 12 N m 1 2 kgf m 8 9 lb ft Silencer bolt M6 1 12 N m 1 2 kgf m 8 9 lb ft Fiber bolt M6 4 10 N m 1 0 kgf m 7 4 lb ft Stator coil screw M6 3 7 N m 0 7 kgf m ...

Page 51: ...ir cap screw M4 2 1 5 N m 0 15 kgf m 1 1 lb ft Front brake hose union bolt M10 1 30 N m 3 0 kgf m 22 lb ft Front brake caliper bolt M8 2 28 N m 2 8 kgf m 21 lb ft Grip cap bolt M6 2 3 8 N m 0 38 kgf m 2 8 lb ft Engine stop switch screw M3 1 0 5 N m 0 05 kgf m 0 37 lb ft Brake pad pin plug M10 2 2 5 N m 0 25 kgf m 1 8 lb ft Brake pad pin M10 2 17 N m 1 7 kgf m 13 lb ft Brake caliper bleed screw M8 ...

Page 52: ...r M8 1 32 N m 3 2 kgf m 24 lb ft Rear frame bolt lower M8 2 29 N m 2 9 kgf m 21 lb ft Brake hose holder screw M5 4 3 5 N m 0 35 kgf m 2 6 lb ft Swingarm and patch screw M4 4 2 0 N m 0 20 kgf m 1 5 lb ft Drive chain tensioner bolt M8 1 16 N m 1 6 kgf m 12 lb ft Drive chain tensioner nut M8 1 16 N m 1 6 kgf m 12 lb ft Drive chain support bolt M6 1 7 N m 0 7 kgf m 5 2 lb ft Drive chain support nut M6...

Page 53: ...the steering ring nut one turn 2 Retighten the steering ring nut 7 N m 0 7 kgf m 5 2 lb ft Screw mud flap 2 1 3 N m 0 13 kgf m 0 95 lb ft Side cover bolt M6 2 7 N m 0 7 kgf m 5 2 lb ft Seat bolt M8 2 19 N m 1 9 kgf m 14 lb ft Number plate bolt M6 1 7 N m 0 7 kgf m 5 2 lb ft Sidestand bolt M10 1 25 N m 2 5 kgf m 18 lb ft Item Thread size Q ty Tightening torques Remarks ...

Page 54: ...CABLE ROUTING DIAGRAM 2 15 EAM20152 CABLE ROUTING DIAGRAM Frame and engine left side view ...

Page 55: ...icle while the end should face the rear side of the vehicle Clamp the clutch cable below the positioning grommet G Pass the air vent hose back of the throttle cable H Pass the air vent hose overflow hose and crankcase breather hose between the frame and connecting rod I Pass the radiator breather hose and YPVS breather hose outside the engine bracket and inside the down tube Then pass the radiator...

Page 56: ...CABLE ROUTING DIAGRAM 2 17 Frame and engine right side view ...

Page 57: ... so doing clamp the ignition coil lead and engine stop switch lead at their protecting tubes D Face the joint connector with its open end downward and there is no pinching with peripheral parts E Pass the CDI magneto lead and radiator breather hose between the frame and the radiator right F Clamp the CDI magneto lead to the frame at its locating tape G After connecting the coupler make sure that t...

Page 58: ...CABLE ROUTING DIAGRAM 2 19 Handlebar front view 0 in 0 mm 0 mm 0 in ...

Page 59: ...e hose so that its pipe portion directs as shown and lightly touches the pro jection on the master cylinder B Pass the engine stop switch lead in the mid dle of the clutch holder C Clamp the engine stop switch lead to the handlebar D Pass the brake hose in front of the number plate and through the cable guide E Pass the clutch cable through the cable guide on the number plate ...

Page 60: ...CABLE ROUTING DIAGRAM 2 21 Rear brake right side view ...

Page 61: ...3 Brake hose A Pass the brake hose into the brake hose holders B If the brake hose contacts the rear shock absorber spring correct its twist C Install the brake hose so that its pipe portion directs as shown and lightly touches the pro jection on the master cylinder ...

Page 62: ...CABLE ROUTING DIAGRAM 2 23 ...

Page 63: ...NG THE COOLANT 3 11 CHASSIS 3 13 ADJUSTING THE FRONT DISC BRAKE 3 13 ADJUSTING THE REAR DISC BRAKE 3 13 CHECKING THE BRAKE FLUID LEVEL 3 14 CHECKING THE FRONT BRAKE PADS 3 14 CHECKING THE REAR BRAKE PADS 3 15 CHECKING THE FRONT BRAKE HOSE 3 15 CHECKING THE REAR BRAKE HOSE 3 15 CHECKING THE BRAKE OPERATION 3 15 BLEEDING THE HYDRAULIC BRAKE SYSTEM 3 15 DRIVE CHAIN SLACK 3 16 LUBRICATING THE DRIVE CH...

Page 64: ...NG AND LUBRICATING THE CABLES 3 24 LUBRICATING THE BRAKE LEVER 3 24 LUBRICATING THE CLUTCH LEVER 3 24 LUBRICATING THE PEDAL 3 24 CHECKING THE SIDESTAND 3 25 LUBRICATING THE SIDESTAND 3 25 ELECTRICAL SYSTEM 3 26 CHECKING THE IGNITION TIMING 3 26 ...

Page 65: ...ace about 7 5 hours Every fifth race about 12 5 hours As required 1 Piston Check piston for carbon deposits and cracks or damage Clean Replace 2 Piston rings Check piston ring end gap and rings for damage Replace 3 Piston pin and small end bearing Check piston pin and small end bearing for damage Replace 4 Cylinder head Check cylinder head for carbon deposits Clean Check cylinder head gasket for d...

Page 66: ... 17 Cooling system Check coolant level and for leak age Check hoses for cracks or dam age Check radiator cap spring opera tion Change coolant Every 2 years 18 Chassis fasteners Check all chassis fitting and fas teners Correct or tighten if necessary 19 Air filter element Clean Replace 20 Frame Clean and check for damage 21 Fuel line Clean and check for leakage 22 Brakes Adjust lever position and p...

Page 67: ...bearing assemblies for looseness Lubricate with molybdenum disul fide grease 28 Sidestand Lubricate with lithium soap based grease 29 Steering head Check operation free play and tighten if necessary Clean and lubricate with lithium soap based grease Replace bearings 30 Tires and wheels Check tire air pressure wheel runout spokes for looseness and tires for wear Tighten sprocket bolts if neces sary...

Page 68: ... 13 3 13 3 14 3 14 3 15 3 15 3 15 3 15 Drive chain Check drive chain slack and alignment Check that the drive chain is lubricated properly 3 16 4 64 4 64 Wheels Check for excessive wear and tire pressure Check for loose spokes and have no excessive play 3 23 3 23 3 24 3 24 Steering Check that the handlebar can be turned smoothly and have no excessive play 3 17 Front forks and rear shock absorber C...

Page 69: ... b Turn the throttle stop screw 2 until the engine runs at the lowest possible speed c Tighten the locknut EAM30475 CHECKING THE THROTTLE GRIP TIP Prior to adjusting throttle grip free play the en gine idling speed should be adjusted 1 Check Throttle grip free play a Out of specification Regulate 2 Adjust Throttle grip free play a Slide the adjuster cover b Loosen the locknut 1 c Turn the adjuster...

Page 70: ... level a Remove the oil check bolt 1 b Inspect the oil level TIP Be sure the machine is positioned straight up when inspecting the oil level WARNING EWA21090 Never attempt to remove the oil check bolt just after high speed operation The heated oil could spout out causing danger Wait un til the oil cools down Oil flows out Oil level is correct Oil does not flow out Oil level is low Add transmission...

Page 71: ...ned TIP If the clutch lever free play cannot be obtained on the handlebar side use the adjuster on the clutch cable side Clutch cable side a Slide the clutch cable cover b Loosen the locknut 1 c Turn the adjuster 2 until the specified clutch lever free play is obtained d Tighten the locknut 1 e Return the clutch cable cover to its original position Oil drain bolt 20 N m 2 0 kgf m 15 lb ft Type Mot...

Page 72: ...filter element a After washing the element with air filter cleaner or kerosene squeeze and dry it completely WARNING EWA19110 Do not use gasoline or organic acid alka line volatile oil for washing NOTICE ECA24280 Do not twist the element when squeezing the element 4 Check Air filter element Damage Replace 5 Apply Yamaha foam air filter oil or other quality foam air filter oil a Put the air filter ...

Page 73: ...ir filter element is prop erly seated in the air filter case The engine should never be operated without the air fil ter element installed otherwise the piston s and or cylinder s may become excessively worn EAM30541 CHECKING THE CARBURETOR JOINT 1 Check Carburetor joint 1 Cracks damage Replace EAM30542 CHECKING THE CARBURETOR HOSES The following procedure applies to all of the fuel and vacuum hos...

Page 74: ...olding the silencer in place with a vise etc b Remove the inner pipe 1 c Replace the fiber 2 d Install the inner pipe TIP Apply heat resistant sealant to the areas shown making sure that there are no gaps in the beads of sealant 5 Check Gasket 1 Damage Replace Refer to ENGINE REMOVAL on page 5 1 TIP Install the gaskets with their depressed a fac ing outward 6 Check Tightening torques 1 1 1 2 Fiber...

Page 75: ...er is not available soft water may be used 4 Start the engine warm this up for several minutes and then stop it 5 Check Coolant level TIP Before checking the coolant level wait a few minutes until the coolant has settled EAM30211 CHECKING THE COOLING SYSTEM 1 Remove Seat Side cover left right Air scoop left right Refer to GENERAL CHASSIS on page 4 1 2 Check Radiator Radiator hoses Crack damage Rep...

Page 76: ... of coolant lowers the antifreeze content of the coolant If water is used instead of coolant check and if nec essary correct the antifreeze concentra tion of the coolant Use only distilled water However if dis tilled water is not available soft water may be used If coolant comes into contact with painted surfaces immediately wash them with wa ter Do not mix different types of antifreeze 7 Install ...

Page 77: ...E ECA13490 After adjusting the brake lever position make sure there is no brake drag 4 Install Brake lever cover EAM30480 ADJUSTING THE REAR DISC BRAKE 1 Check Brake pedal position a Out of specification Adjust 2 Adjust Brake pedal position a Loosen the locknut 1 b Turn the adjusting nut 2 until the speci fied brake pedal position is obtained WARNING EWA20710 Adjust the pedal height between the ma...

Page 78: ...bber 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 chemical 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 va...

Page 79: ... Check Brake operation Brake not working properly Check the brake system Refer to FRONT BRAKE on page 4 11 and REAR BRAKE on page 4 22 TIP Drive on the dry road operate the front and rear brakes separately and check to see if the brakes are operating properly EAM30477 BLEEDING THE HYDRAULIC BRAKE SYSTEM WARNING EWA19140 Bleed the brake system whenever The system is disassembled A brake hose is loo...

Page 80: ...d immediately i Tighten the bleed screw j Pour brake fluid to the reservoir up to the specified level Refer to CHECKING THE BRAKE FLUID LEVEL on page 3 14 WARNING EWA13110 After bleeding the hydraulic brake system check the brake operation EAM30481 DRIVE CHAIN SLACK NOTICE ECA13550 A drive chain that is too tight will overload the engine and other vital parts and one that is too loose can skip and...

Page 81: ...g high pressure washing certain solvents and the use of a coarse brush can damage these O rings Therefore use only kerosene to clean the drive chain Wipe the drive chain dry and thoroughly lubricate it with engine oil or chain lubricant that is suitable 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 EAM30247 CHECKI...

Page 82: ...ns If any binding is felt re move the lower bracket and check the up per and lower bearings Refer to STEERING HEAD on page 4 50 f Install the washer 1 5 Install Upper bracket Refer to STEERING HEAD on page 4 50 Handlebar Refer to HANDLEBAR on page 4 32 EAM30502 LUBRICATING THE STEERING HEAD 1 Lubricate Upper bearing Lower bearing Bearing race EAM30338 CHECKING THE FRONT FORK LEGS 1 Stand the vehic...

Page 83: ...nt forks evenly If this is not done the vehicle may have poor stability Securely support the vehicle so that there is no danger of it falling over Rebound damping NOTICE ECA24340 Do not turn the adjuster forcibly beyond its adjusting range 1 Adjust Rebound damping a Turn the adjuster 1 in the direction of a or b to make an adjustment TIP Although the total number of clicks of a damping force adjus...

Page 84: ...f during a run relieve the front fork internal pressure 1 Use a maintenance stand to raise the front wheel off the ground WARNING EWA13120 Securely support the vehicle so that there is no danger of it falling over 2 Remove the bleed screw 1 and release the internal pressure from the front fork 3 Tighten Bleed screw EAM30482 CHECKING THE REAR SHOCK ABSORBER ASSEMBLY 1 Stand the vehicle upright on a...

Page 85: ...d the ad juster c Measure the spring free length a d Turn the adjuster in the direction of b or c to make an adjustment TIP Be sure to remove all dirt and mud from around the locknut and adjusting ring before adjust ment The length of the spring installed changes 1 5 mm 0 06 in per turn of the adjusting ring e Tighten the locknut 3 Install Rear frame Refer to REAR SHOCK ABSORBER AS SEMBLY on page ...

Page 86: ...cations listed due to small differences in production Compression damping for slow compres sion damping NOTICE ECA24390 Do not turn the adjuster forcibly beyond its adjusting range 1 Adjust Compression damping for slow compression damping a Turn the adjuster 1 in the direction of a or b to make an adjustment Direction a Rebound damping is increased sus pension is harder Direction b Rebound damping...

Page 87: ... 56 EAM30243 CHECKING THE TIRES 1 Measure Tire pressure Out of specification Regulate TIP Check the tire while it is cold Because if the bead stopper tightening nut is loose when the tire pressure is low the tire could slip off the rim thus be sure to check and tighten the bead stopper tightening nut a If the tire valve stem b is found tilted the tire is considered to be slipping off its position ...

Page 88: ...lies to all of the in ner and outer cables WARNING EWA13270 Damaged outer cable may cause the cable to corrode and interfere with its movement Re place damaged outer cable and inner cables as soon as possible 1 Check Outer cable Damage Replace 2 Check Cable operation Rough movement Lubricate TIP Hold the cable end upright and pour a few drops of lubricant into the cable sheath or use a suit able l...

Page 89: ...ck that the sidestand moves smoothly Rough movement Repair or replace EAM30252 LUBRICATING THE SIDESTAND Lubricate the pivoting point and metal to metal moving parts of the sidestand Recommended lubricant Lithium soap based grease Recommended lubricant Lithium soap based grease ...

Page 90: ...n the same direction 4 Set the dial gauge to zero at TDC 5 From TDC rotate the rotor clockwise until the dial gauge indicates that the piston is at a specified distance from TDC 6 Check Ignition timing Punch mark a on rotor should be aligned with punch mark b on stator Not aligned Adjust 7 Adjust Ignition timing a Loosen the stator coil screws 1 b Align the punch mark on the rotor with punch mark ...

Page 91: ... 17 DISASSEMBLING THE FRONT BRAKE CALIPER 4 17 CHECKING THE FRONT BRAKE CALIPER 4 17 ASSEMBLING THE FRONT BRAKE CALIPER 4 18 INSTALLING THE FRONT BRAKE CALIPER 4 18 REMOVING THE FRONT BRAKE MASTER CYLINDER 4 19 CHECKING THE FRONT BRAKE MASTER CYLINDER 4 19 ASSEMBLING THE FRONT BRAKE MASTER CYLINDER 4 19 INSTALLING THE FRONT BRAKE MASTER CYLINDER 4 20 REAR BRAKE 4 22 INTRODUCTION 4 26 CHECKING THE ...

Page 92: ...51 REAR SHOCK ABSORBER ASSEMBLY 4 54 HANDLING THE REAR SHOCK ABSORBER 4 56 DISPOSING OF A REAR SHOCK ABSORBER 4 56 REMOVING THE REAR SHOCK ABSORBER ASSEMBLY 4 56 CHECKING THE REAR SHOCK ABSORBER ASSEMBLY 4 56 CHECKING THE CONNECTING ARM AND RELAY ARM 4 56 INSTALLING THE RELAY ARM 4 57 INSTALLING THE REAR SHOCK ABSORBER ASSEMBLY 4 57 SWINGARM 4 59 REMOVING THE SWINGARM 4 60 CHECKING THE SWINGARM 4 ...

Page 93: ...Air scoop left and right 2 3 Side cover left 1 4 Side cover right 1 5 Number plate 1 1 5 2 4 3 2 19 N m 1 9 kgf m 14 lb ft 7 N m 0 7 kgf m 5 2 lb ft 7 N m 0 7 kgf m 5 2 lb ft 6 N m 0 6 kgf m 4 4 lb ft 7 N m 0 7 kgf m 5 2 lb ft 7 N m 0 7 kgf m 5 2 lb ft 6 N m 0 6 kgf m 4 4 lb ft 19 N m 1 9 kgf m 14 lb ft 7 N m 0 7 kgf m 5 2 lb ft ...

Page 94: ... b on the number plate The projection c on the lower bracket is in serted into the number plate Remove the number plate by pulling it off the projection When installing the number plate insert the projection on the number plate into the hole in the upper side of the band EAM30459 REMOVING THE SIDE COVER 1 Remove Side cover bolt Side cover left and right 1 TIP Draw the side cover backward to remove...

Page 95: ...d to raise the front wheel off the ground 1 Front wheel axle pinch bolt 4 Loosen 2 Front wheel axle nut 1 3 Front wheel axle 1 4 Front wheel 1 5 Collar 2 6 Oil seal 2 7 Bearing 2 8 Brake disc 1 12 N m 1 2 kgf m 8 9 lb ft 1 2 3 4 5 6 7 8 21 N m 2 1 kgf m 15 lb ft 105 N m 10 5 kgf m 77 lb ft 21 N m 2 1 kgf m 15 lb ft 5 6 7 1 ...

Page 96: ...e Bends Replace WARNING EWA13460 Do not attempt to straighten a bent wheel ax le 2 Check Tire Front wheel Damage wear Replace Refer to CHECKING THE TIRES on page 3 23 and CHECKING THE WHEELS on page 3 24 3 Check Spoke Bend damage Replace Loose Tighten Tap the spokes with a screwdriver TIP A tight spoke will emit a clear ringing tone a loose spoke will sound flat 4 Tighten Spoke Refer to CHECKING A...

Page 97: ...E ECA18110 Do not contact the wheel bearing inner race 1 or balls 2 Contact should be made only with the outer race 3 TIP Use a socket 4 that matches the diameter of the bearing outer race and that of the oil seal 2 Install Brake disc Brake disc bolt TIP Tighten the bolts in stages and in a crisscross pattern 3 Install Collar 1 TIP Apply the lithium soap based grease on the oil seal lip Install th...

Page 98: ...t wheel axle nut 1 NOTICE ECA24430 Before tightening the front wheel axle nut push down hard on the handlebar s several times and check if the front fork rebounds smoothly 4 Tighten Front wheel axle pinch bolt 1 Front wheel axle nut 105 N m 10 5 kgf m 77 lb ft Front wheel axle pinch bolt 21 N m 2 1 kgf m 15 lb ft 1 T R T R ...

Page 99: ... off the ground 1 Rear wheel axle nut 1 2 Rear wheel axle 1 3 Drive chain puller 2 4 Rear wheel 1 5 Collar 2 6 Rear wheel sprocket 1 7 Oil seal 2 8 Circlip 1 9 Bearing 2 10 Brake disc 1 19 N m 1 9 kgf m 14 lb ft 42 N m 4 2 kgf m 31 lb ft 125 N m 12 5 kgf m 92 lb ft 12 N m 1 2 kgf m 8 9 lb ft 19 N m 1 9 kgf m 14 lb ft 1 2 3 4 5 6 7 8 9 10 5 3 7 9 ...

Page 100: ...amage wear Replace Refer to CHECKING THE TIRES on page 3 23 and CHECKING THE WHEELS on page 3 24 3 Check Spoke Refer to CHECKING THE FRONT WHEEL on page 4 4 4 Measure Radial wheel runout Lateral wheel runout Refer to CHECKING THE FRONT WHEEL on page 4 4 EAM30025 CHECKING AND REPLACING THE REAR WHEEL SPROCKET 1 Check Rear wheel sprocket More than 1 4 tooth wear a Replace the rear wheel sprocket and...

Page 101: ... ECA24440 Install the bearing by pressing its outer race parallel NOTICE ECA18110 Do not contact the wheel bearing inner race 1 or balls 2 Contact should be made only with the outer race 3 TIP Use a socket 4 that matches the diameter of the bearing outer race and that of the oil seal 2 Install Brake disc Brake disc bolt TIP Tighten the bolts in stages and in a crisscross pattern 3 Install Collar 1...

Page 102: ...soap based grease to the rear wheel axle 4 Install Right drive chain puller 1 Washer 2 Rear wheel axle nut 3 TIP Temporarily tighten the rear wheel axle nut at this point 5 Adjust Drive chain slack a Refer to DRIVE CHAIN SLACK on page 3 16 6 Tighten Rear wheel axle nut 1 Locknut 2 1 2 Drive chain slack Maintenance stand 48 0 58 0 mm 1 89 2 28 in Rear wheel axle nut 125 N m 12 5 kgf m 92 lb ft Driv...

Page 103: ... SYSTEM on page 3 15 1 Union bolt 1 2 Copper washer 2 3 Front brake hose 1 4 Brake pad pin plug 1 5 Brake pad pin 1 6 Brake pad 2 7 Brake pad spring 1 8 Front brake caliper assembly 1 9 Front brake caliper bracket 1 3 9 1 2 8 4 5 7 6 28 N m 2 8 kgf m 21 lb ft 30 N m 3 0 kgf m 22 lb ft 2 5 N m 0 25 kgf m 1 8 lb ft 17 N m 1 7 kgf m 13 lb ft 6 N m 0 6 kgf m 4 4 lb ft ...

Page 104: ... Disassembling the front brake caliper Order Job Parts to remove Q ty Remarks 1 Brake caliper piston 2 2 Brake caliper piston dust seal 2 3 Brake caliper piston seal 2 4 Bleed screw 1 1 2 3 4 6 N m 0 6 kgf m 4 4 lb ft ...

Page 105: ...ion bolt 1 3 Copper washer 2 4 Front brake hose 1 5 Brake master cylinder reservoir cap 1 6 Brake master cylinder reservoir diaphragm 1 7 Front brake master cylinder float 1 8 Front brake master cylinder holder 1 9 Front brake master cylinder 1 5 6 7 2 3 4 8 9 1 30 N m 3 0 kgf m 22 lb ft 6 N m 0 6 kgf m 4 4 lb ft 6 N m 0 6 kgf m 4 4 lb ft 1 5 N m 0 15 kgf m 1 1 lb ft 9 N m 0 9 kgf m 6 6 lb ft ...

Page 106: ...FRONT BRAKE 4 14 Disassembling the front brake master cylinder Order Job Parts to remove Q ty Remarks 1 Push rod 1 2 Dust boot 1 3 Circlip 1 4 Washer 1 5 Brake master cylinder kit 1 5 4 3 2 1 New New ...

Page 107: ...cation Replace 3 Measure Brake disc runout Out of specification Correct the brake disc runout or replace the brake disc a Place the vehicle on a maintenance stand so that the front wheel is elevated b Remove the brake caliper c Hold the dial gauge at a right angle against the brake disc surface d Measure the runout 1 5 mm 0 06 in above the brake disc edge 4 Adjust Brake disc runout a Remove the fr...

Page 108: ...ew and push the brake caliper piston in WARNING EWA19160 Do not reuse the drained brake fluid c Tighten the bleed screw d Install the brake pads 3 and the pad pin TIP Install the brake pads with their projections a into the brake caliper recesses b Temporarily tighten the pad pin at this point e Install the brake caliper 4 and tighten the pad pin 5 Brake pad lining thickness limit 1 0 mm 0 04 in 4...

Page 109: ...on 1 Brake caliper piston dust seal 2 Brake caliper piston seal 3 a Blow compressed air into the brake hose joint opening to force out the piston from the brake caliper WARNING EWA13550 Cover the brake caliper piston with a rag Be careful not to get injured when the pis ton is expelled from the brake caliper Never try to pry out the brake caliper pis ton b Remove the brake caliper piston dust seal...

Page 110: ...PER 1 Install Front brake caliper bracket Front brake caliper temporarily Copper washer Brake hose Union bolt WARNING EWA13531 Proper brake hose routing is essential to in sure safe vehicle operation NOTICE ECA24460 Make sure that the pipe portion a of the brake hose touches the projection b on the brake caliper 2 Install Front brake caliper Brake pad spring Brake pad Brake pad pin Brake hose hold...

Page 111: ...5 EAM30036 REMOVING THE FRONT BRAKE MASTER CYLINDER TIP Before removing the front brake master cylinder drain the brake fluid from the entire brake sys tem 1 Remove Union bolt Copper washer Brake hose TIP To drain any remaining brake fluid place a con tainer under the master cylinder and the end of the brake hose EAM30037 CHECKING THE FRONT BRAKE MASTER CYLINDER 1 Check Brake master cylinder 1 Dam...

Page 112: ... install the circlip EAM30039 INSTALLING THE FRONT BRAKE MASTER CYLINDER 1 Install Brake master cylinder 1 TIP Install the front brake master cylinder holder with the UP mark a facing up First tighten the upper bolt then the lower bolt 2 Install Copper washer 1 Brake hose 2 Union bolt 3 WARNING EWA13531 Proper brake hose routing is essential to in sure safe vehicle operation NOTICE ECA24470 During...

Page 113: ... chemical 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 NOTICE ECA13540 Brake fluid may damage painted surfaces and plastic parts Therefore always clean up any spilt brake fluid immediately 4 Bleed Brake system Refer to BLEEDING T...

Page 114: ...t 1 3 Copper washer 2 4 Rear brake hose 1 5 Brake pad pin plug 1 6 Brake pad pin 1 7 Rear brake pad assembly 2 8 Rear brake caliper bracket 1 9 Brake pad spring 1 10 Rear brake disc cover 1 11 Rear brake caliper assembly 1 17 N m 1 7 kgf m 13 lb ft 2 5 N m 0 25 kgf m 1 8 lb ft 30 N m 3 0 kgf m 22 lb ft 7 N m 0 7 kgf m 5 2 lb ft 10 N m 1 0 kgf m 7 4 lb ft 10 N m 1 0 kgf m 7 4 lb ft 11 10 7 9 7 8 6 ...

Page 115: ... Disassembling the rear brake caliper Order Job Parts to remove Q ty Remarks 1 Brake caliper piston 1 2 Brake caliper piston dust seal 1 3 Brake caliper piston seal 1 4 Bleed screw 1 1 2 3 4 6 N m 0 6 kgf m 4 4 lb ft ...

Page 116: ...page 3 15 1 Union bolt 1 2 Copper washer 2 3 Brake hose 1 4 Split pin 1 5 Washer 1 6 Pin 1 7 Brake master cylinder reservoir cap 1 8 Brake master cylinder reservoir diaphragm plate 1 9 Brake master cylinder reservoir diaphragm 1 10 Rear brake master cylinder 1 1 2 3 7 5 8 6 9 4 10 30 N m 3 0 kgf m 22 lb ft 10 N m 1 0 kgf m 7 4 lb ft 1 5 N m 0 15 kgf m 1 1 lb ft ...

Page 117: ...REAR BRAKE 4 25 Disassembling the rear brake master cylinder Order Job Parts to remove Q ty Remarks 1 Dust boot 1 2 Circlip 1 3 Push rod 1 4 Brake master cylinder kit 1 4 3 2 1 New New ...

Page 118: ... mediate medical attention EAM30041 CHECKING THE REAR BRAKE DISC 1 Check Brake disc Damage galling Replace 2 Measure Brake disc thickness Measure the brake disc thickness at a few dif ferent locations Out of specification Replace Refer to CHECKING THE FRONT BRAKE DISC on page 4 15 3 Measure Brake disc runout Out of specification Correct the brake disc runout or replace the brake disc Refer to CHEC...

Page 119: ...3 and the pad pin 4 TIP Install the brake pads with their projections a into the brake caliper recesses b Temporarily tighten the pad pin at this point e Install the brake caliper 5 and the rear wheel 6 Refer to REAR WHEEL on page 4 7 f Tighten the pad pin 7 g Install the pad pin plug 8 and the protector 9 Brake pad lining thickness limit 1 0 mm 0 04 in Brake caliper bleed screw 6 N m 0 6 kgf m 4 ...

Page 120: ... the brake caliper piston with a rag Be careful not to get injured when the pis ton is expelled from the brake caliper Never try to pry out the brake caliper pis ton b Remove the brake caliper piston dust seal and the brake caliper piston seal EAM30044 CHECKING THE REAR BRAKE CALIPER 1 Check Brake caliper piston 1 Rust scratches wear Replace the brake caliper piston Brake caliper cylinder 2 Scratc...

Page 121: ...e 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 chemical 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 NOTICE ECA13540...

Page 122: ...Replace 4 Check Brake hose Cracks damage wear Replace EAM30050 ASSEMBLING THE REAR BRAKE MASTER CYLINDER WARNING EWA13520 Before installation all internal brake com ponents should be cleaned and lubricated with clean or new brake fluid Never use solvents on internal brake com ponents 1 Wash the brake master cylinder and the brake master cylinder kit with brake fluid 2 Install Primary cylinder cup ...

Page 123: ...ing 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 chemical 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 NOTICE ECA24510 Brake...

Page 124: ...linder 1 5 Throttle cable cap 1 6 Throttle cable 1 7 Right grip 1 8 Cap cover 1 9 Collar 1 10 Left grip 1 11 Upper handlebar holder 2 12 Handlebar 1 13 Lower handlebar holder 2 1 2 12 11 13 4 7 9 5 6 3 10 8 0 5 N m 0 05 kgf m 0 37 lb ft 9 N m 0 9 kgf m 6 6 lb ft 28 N m 2 8 kgf m 21 lb ft 5 N m 0 5 kgf m 3 7 lb ft 0 5 N m 0 05 kgf m 0 37 lb ft 4 8 N m 0 48 kgf m 3 5 lb ft 4 3 N m 0 43 kgf m 3 2 lb ...

Page 125: ...hicle upright on a level surface WARNING EWA13120 Securely support the vehicle so that there is no danger of it falling over 2 Install Lower handlebar holder 1 Washer 2 Lower handlebar holder nut 3 TIP Install the lower handlebar holders with them side having the greater distance a from the mounting bolt center facing forward Apply the lithium soap base grease on the thread of the lower handlebar ...

Page 126: ... adhesive wipe off grease or oil on the handlebar surface a with a lac quer thinner Install the left grip to the handlebar so that the line b between the two arrow marks faces straight upward 6 Install Engine stop switch 1 Clutch lever holder 2 Clutch lever holder bolt 3 Clamp 4 TIP The engine stop switch clutch lever holder and clamp should be installed according to the di mensions shown Lower ha...

Page 127: ...2 TIP Before applying the adhesive wipe off grease or oil on the tube guide surface a with a lac quer thinner Align the mating mark b on the right grip with the slot c in the tube guide 10 Install Grip cap upper 1 Grip cap lower 2 Grip cap bolt 3 TIP Temporarily tighten the grip cap bolts 11 Install Collar 1 Grip cap cover 2 Throttle grip 3 TIP Apply the lithium soap base grease on the throttle gr...

Page 128: ...tall Throttle cable cap 1 Throttle cable cap screw 2 15 Adjust Throttle grip free play Refer to CHECKING THE THROTTLE GRIP on page 3 5 16 Install Cap cover 1 17 Install Brake master cylinder 1 Brake master cylinder holder 2 Front brake master cylinder holder bolt 3 TIP Install the holder so that the arrow mark a fac es upward First tighten the bolt on the upper side of the brake master cylinder ho...

Page 129: ...7 18 Install Grip cap bolt 1 WARNING EWA21080 After tightening the bolts check that the throttle grip 2 moves smoothly If it does not retighten the bolts for adjustment Grip cap bolt 3 8 N m 0 38 kgf m 2 8 lb ft T R ...

Page 130: ...T WHEEL on page 4 3 Front brake caliper Refer to FRONT BRAKE on page 4 11 Number plate Refer to GENERAL CHASSIS on page 4 1 1 Protector 1 2 Upper bracket pinch bolt 2 Loosen 3 Damper assembly 1 Loosen 4 Lower bracket pinch bolt 2 Loosen 5 Front fork leg 1 5 N m 0 5 kgf m 3 7 lb ft 5 N m 0 5 kgf m 3 7 lb ft 9 N m 0 9 kgf m 6 6 lb ft 21 N m 2 1 kgf m 15 lb ft 21 N m 2 1 kgf m 15 lb ft 3 2 4 5 1 ...

Page 131: ... 5 Stopper ring 1 6 Inner tube 1 7 Outer tube 1 8 Piston metal 1 9 Protector guide 1 10 Slide metal 1 11 Washer 1 12 Oil seal 1 13 Base valve 1 14 Damper assembly 1 15 Upper spring seat 1 29 N m 2 9 kgf m 21 lb ft 30 N m 3 0 kgf m 22 lb ft 29 N m 2 9 kgf m 21 lb ft 55 N m 5 5 kgf m 41 lb ft 1 3 N m 0 13 kgf m 0 95 lb ft 10 7 15 2 14 6 1 4 5 8 11 12 3 13 9 ...

Page 132: ...ork leg EAM30056 DISASSEMBLING THE FRONT FORK LEGS 1 Drain Fork oil 2 Remove Adjuster 1 from the inner tube TIP While compressing the inner tube 2 set the cap bolt ring wrench 4 between the inner tube and locknut 3 Hold the locknut and remove the adjuster NOTICE ECA24520 Do not remove the locknut as the damper rod may go into the damper assembly and not be taken out 3 Remove Dust seal 1 Stopper ri...

Page 133: ...usly weaken it 2 Check Outer tube Scratches wear damage Replace 3 Measure Fork spring free length a Out of specification Replace 4 Check Damper assembly 1 Bend damage Replace O ring 2 Wear damage Replace NOTICE ECA14200 The front fork leg has a built in damper ad justing rod and a very sophisticated inter nal construction which are particularly sensitive to foreign material When disassembling and ...

Page 134: ...efore assembling the front fork leg make sure that all of the components are clean 1 Stretch the damper assembly fully 2 Fill Damper assembly NOTICE ECA24530 Be sure to use the recommended oil Other oils may have an adverse effect on front fork performance When disassembling and assembling the front fork leg take care not to allow any for eign material to enter the front fork 3 After filling pump ...

Page 135: ... TIP First bring the damper rod pressure to a maxi mum Then install the base valve while releasing the damper rod pressure 8 Check Damper assembly Not fully stretched Repeat the steps 1 to 7 9 Tighten Base valve 1 TIP Hold the damper assembly with the cap bolt ring wrench 2 and use the cap bolt wrench 3 to tighten the base valve Standard oil level 145 148 mm 5 71 5 83 in From top of fully stretche...

Page 136: ...amper assembly TIP The overflow measures about 10 cm 0 34 US oz 0 35 Imp oz 13 Check Damper assembly smooth movement Tightness binding rough spots Repeat the steps 1 to 12 14 Install Dust seal 1 Stopper ring 2 Oil seal 3 Washer 4 Slide metal 5 to the inner tube 6 NOTICE ECA24550 Make sure that the numbered side of the oil seal faces bottom side TIP Apply the lithium soap based grease on the dust s...

Page 137: ... 18 Install Oil seal 1 TIP Using a fork seal driver 2 press the oil seal in until the stopper ring groove fully appears 19 Install Stopper ring 1 TIP Fit the stopper ring correctly in the groove in the outer tube 20 Install Dust seal 1 TIP Apply lithium soap based grease on the inner tube Fork seal driver 90890 01502 Fork seal driver 48 YM A0948 G088922 New New Fork seal driver 90890 01502 Fork se...

Page 138: ...CE ECA24560 Allow the damper assembly to slide slowly down the inner tube until it contacts the bot tom of the inner tube Be careful not to dam age the inner tube 25 Loosen Rebound damping force adjuster 1 TIP Before loosening the damping force adjuster record the setting position Unless the damping force adjuster is fully loos ened correct damping characteristic cannot be obtained after installat...

Page 139: ...he adjuster 29 Install Adjuster 1 to the inner tube 30 Fill Front fork leg NOTICE ECA24570 Be sure to use the recommended oil Other oils may have an adverse effect on front fork performance When disassembling and assembling the front fork leg do not allow any foreign ma terial to enter the front fork Cap bolt ring wrench 90890 01501 Cap bolt ring wrench YM 01501 Gap a between the adjuster and the ...

Page 140: ...tighten the pinch bolts lower bracket Do not tighten the pinch bolts upper bracket yet 2 Tighten Damper assembly 1 TIP Use the cap bolt ring wrench 2 to tighten the damper assembly 3 Adjust Front fork top end a 4 Tighten Upper bracket pinch bolt 1 1 Damper assembly front fork 30 N m 3 0 kgf m 22 lb ft Cap bolt ring wrench 90890 01501 Cap bolt ring wrench YM 01501 Front fork top end standard a 5 mm...

Page 141: ...st Rebound damping force TIP Turn in the damping adjuster 1 finger tight and then turn out to the originally set position 7 Adjust Compression damping force TIP Turn in the damping adjuster 1 finger tight and then turn out to the originally set position Upper bracket pinch bolt 21 N m 2 1 kgf m 15 lb ft Lower bracket pinch bolt 21 N m 2 1 kgf m 15 lb ft Front fork protector bolt 5 N m 0 5 kgf m 3 ...

Page 142: ...r to HANDLEBAR on page 4 32 1 Front fender 1 2 Steering stem nut 1 3 Front fork leg 2 4 Upper bracket 1 5 Steering ring nut 1 6 Lower bracket 1 7 Bearing race cover 1 8 Upper bearing 1 9 Lower bearing 1 10 Bearing race 2 5 4 2 10 7 8 9 3 6 1 10 N m 1 0 kgf m 7 4 lb ft 3 8 N m 0 38 kgf m 2 8 lb ft 21 N m 2 1 kgf m 15 lb ft 145 N m 14 5 kgf m 107 lb ft 21 N m 2 1 kgf m 15 lb ft 1st 2nd 38 N m 3 8 kg...

Page 143: ... Bearing race a Remove the bearing race from the steer ing head pipe 1 with a long rod 2 and a hammer b Remove the bearing race from the lower bracket 3 with a chisel 4 and a hammer c Install a new bearing race NOTICE ECA14270 If the bearing race is not installed properly the steering head pipe could be damaged TIP Always replace the bearing and the bearing race as a set 4 Check Upper bracket Lowe...

Page 144: ...g nut with its stepped side a facing downward Tighten the steering ring nut with a steering nut wrench 2 Refer to CHECKING AND ADJUSTING THE STEERING HEAD on page 3 17 5 Check the steering stem by turning this lock to lock If there is any binding remove the steering stem and check the steering bear ing 6 Install Washer 1 7 Install Front fork 1 Upper bracket 2 TIP Temporarily tighten the lower brac...

Page 145: ...e steering ring nut little by lit tle 10 Adjust Front fork top end a 11 Tighten Upper bracket pinch bolt 1 Lower bracket pinch bolt 2 WARNING EWA19330 Tighten the lower bracket to specified torque If torqued too much it may cause the front fork to malfunction Steering stem nut 145 N m 14 5 kgf m 107 lb ft Front fork top end standard a 5 mm 0 2 in T R a Upper bracket pinch bolt 21 N m 2 1 kgf m 15 ...

Page 146: ...lamp 1 2 Rear frame 1 3 Rear shock absorber assembly lower bolt 1 4 Rear shock absorber assembly upper bolt 1 5 Rear shock absorber assembly 1 6 Locknut 1 7 Adjusting nut 1 8 Lower spring guide 1 9 Upper spring guide 1 10 Spring 1 11 Dust seal 4 12 Collar 4 13 Bearing 1 14 Bushing 1 4 12 12 11 11 14 5 6 9 8 3 1 2 13 12 12 11 11 7 10 29 N m 2 9 kgf m 21 lb ft 32 N m 3 2 kgf m 24 lb ft 56 N m 5 6 kg...

Page 147: ...BLY 4 55 Disassembling the relay arm Order Job Parts to remove Q ty Remarks 1 Relay arm 1 2 Connecting arm 1 3 Collar 3 4 Oil seal 6 5 Washer 8 6 Bearing 6 80 N m 8 0 kgf m 59 lb ft 4 6 3 6 6 5 5 6 1 4 4 3 5 2 4 4 5 5 4 5 3 6 6 ...

Page 148: ...WA19340 Wear protective glasses to prevent your eyes from damage due to possible gas or metal chips scattered To dispose of a damaged or a worn out rear shock absorber take the unit to your Yamaha dealer for this disposal procedure EAM30065 REMOVING THE REAR SHOCK ABSORBER ASSEMBLY 1 Use a maintenance stand to raise the rear wheel off the ground WARNING EWA13120 Securely support the vehicle so tha...

Page 149: ...he bearing is press fitted 2 Lubricate O ring 3 Install Bearing Stopper ring to rear shock absorber assembly upper side TIP Install the bearing parallel until the stopper ring groove appears by pressing its outer race After installing the stopper ring push back the bearing until it contacts the stopper ring 4 Install Bearing 1 Bushing 2 Collar 3 Dust seal 4 to rear shock absorber assembly lower si...

Page 150: ...Rear shock absorber assembly upper nut Connecting arm nut frame side Connecting arm nut relay arm side Relay arm nut swingarm side Rear shock absorber assembly lower nut 8 Install Rear frame 1 Rear frame bolt upper 2 Rear frame bolt lower 3 9 Tighten Air filter case joint clamp 1 Recommended lubricant Molybdenum disulfide grease Rear shock absorber assembly upper nut 56 N m 5 6 kgf m 41 lb ft Conn...

Page 151: ...fer to REAR BRAKE on page 4 22 Rear brake caliper Refer to REAR BRAKE on page 4 22 Bolt brake pedal Drive chain 1 Collar 2 2 Oil seal 2 3 Thrust bearing 2 4 Bushing 2 5 Oil seal 2 6 Bearing 4 6 N m 0 6 kgf m 4 4 lb ft 2 0 N m 0 20 kgf m 1 5 lb ft 70 N m 7 0 kgf m 52 lb ft 7 N m 0 7 kgf m 5 2 lb ft 7 N m 0 7 kgf m 5 2 lb ft 85 N m 8 5 kgf m 63 lb ft 5 6 6 1 1 2 3 6 3 2 6 5 4 4 ...

Page 152: ...ks damage Replace 2 Check Pivot shaft Roll the pivot shaft on a flat surface Bends Replace WARNING EWA13770 Do not attempt to straighten a bent pivot shaft 3 Wash with kerosene Pivot shaft Bushing Collar Bearing 4 Check Oil seal Damage Replace Bearing Thrust bearing Bushing Free play exists unsmooth revolution rust Replace bearing and bushing as a set EAM30074 INSTALLING THE SWINGARM 1 Lubricate B...

Page 153: ...SWINGARM 4 61 4 Install Rear wheel Refer to REAR WHEEL on page 4 7 5 Adjust Drive chain slack Refer to DRIVE CHAIN SLACK on page 3 16 Drive chain slack Maintenance stand 48 0 58 0 mm 1 89 2 28 in ...

Page 154: ...rder Job Parts to remove Q ty Remarks Drive sprocket Refer to ENGINE REMOVAL on page 5 1 1 Drive chain 1 2 Drive sprocket cover 1 3 Bracket 1 4 Drive sprocket nut 1 5 Lock washer 1 6 Drive sprocket 1 1 2 2 3 4 5 6 5 N m 0 5 kgf m 3 7 lb ft 75 N m 7 5 kgf m 55 lb ft ...

Page 155: ...ween pin outer sides 2 TIP When measuring a 15 link section of the drive chain make sure that the drive chain is taut Perform this procedure 2 3 times at a different location each time 2 Check Drive chain Stiffness Clean lubricate or replace 3 Clean Drive chain a Wipe the drive chain with a clean cloth b Put the drive chain in kerosene and re move any remaining dirt c Remove the drive chain from t...

Page 156: ...CHECKING AND REPLACING THE REAR WHEEL SPROCKET on page 4 8 EAM30079 INSTALLING THE DRIVE CHAIN 1 Install Drive chain NOTICE ECA17410 Be sure to put on safety goggles when work ing TIP Install the master link with the drive chain cut rivet tool Use goods on the market a When press fitting the master link plate 1 make sure the space a between the end of the connecting pin 2 and the mas ter link plat...

Page 157: ...prockets this will dramatically shorten the drive chain s life 4 Adjust Drive chain slack Refer to DRIVE CHAIN SLACK on page 3 16 NOTICE ECA24590 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 swing arm or cause an accident Therefore keep the drive chain slack within the specified lim its Recommended lubricant Chain ...

Page 158: ...CHAIN DRIVE 4 66 ...

Page 159: ...12 INSTALLING THE CYLINDER HEAD 5 14 CDI MAGNETO 5 15 REMOVING THE ROTOR 5 16 CHECKING THE CDI MAGNETO 5 16 CHECKING THE WOODRUFF KEY 5 16 INSTALLING THE CDI MAGNETO 5 16 KICKSTARTER 5 18 REMOVING THE PRIMARY DRIVE GEAR 5 20 REMOVING THE KICK SHAFT ASSEMBLY 5 20 CHECKING THE KICK GEAR AND KICK IDLE GEAR 5 20 INSTALLING THE KICK SHAFT ASSEMBLY 5 20 INSTALLING THE KICK IDLE GEAR 5 21 INSTALLING THE ...

Page 160: ...NG THE SHIFT SHAFT 5 33 CHECKING THE STOPPER LEVER 5 33 INSTALLING THE SHIFT SHAFT 5 33 CRANKCASE 5 36 DISASSEMBLING THE CRANKCASE 5 37 CHECKING THE CRANKCASE 5 37 ASSEMBLING THE CRANKCASE 5 37 CRANKSHAFT 5 40 REMOVING THE CRANKSHAFT 5 41 CHECKING THE CRANKSHAFT 5 41 INSTALLING THE CRANKSHAFT 5 41 TRANSMISSION 5 43 REMOVING THE TRANSMISSION 5 44 CHECKING THE SHIFT FORKS 5 44 CHECKING THE SHIFT DRU...

Page 161: ...er 1 ø 26 mm 1 02 in 2 Washer 1 ø 22 mm 0 87 in 3 Silencer 1 4 Collar 1 L 15 5 mm 0 61 in 5 Collar 1 L 13 5 mm 0 53 in 6 Grommet front 1 7 Grommet rear 1 8 Tension spring 2 9 Exhaust pipe 1 1 2 3 4 5 6 7 8 9 12 N m 1 2 kgf m 8 9 lb ft 12 N m 1 2 kgf m 8 9 lb ft 12 N m 1 2 kgf m 8 9 lb ft 10 N m 1 0 kgf m 7 4 lb ft 12 N m 1 2 kgf m 8 9 lb ft 15 mm 0 59 in 17 mm 0 67 in ...

Page 162: ...OVAL on page 5 1 Exhaust pipe stay rear Refer to ENGINE REMOVAL on page 5 1 Clutch cable Disconnect at engine side Radiator Refer to RADIATOR on page 6 2 Spark plug CDI magneto lead Disconnect 1 Drive chain sprocket cover 1 2 Drive chain sprocket guide 1 3 Lock washer 1 4 Drive sprocket 1 5 Brake pedal 1 6 Spring 1 7 Engine bracket 2 8 Pivot shaft 1 34 N m 3 4 kgf m 25 lb ft 1 3 4 5 7 5 N m 0 5 kg...

Page 163: ...oving the engine Order Job Parts to remove Q ty Remarks 9 Engine 1 34 N m 3 4 kgf m 25 lb ft 9 5 N m 0 5 kgf m 3 7 lb ft 64 N m 6 4 kgf m 47 lb ft 75 N m 7 5 kgf m 55 lb ft 85 N m 8 5 kgf m 63 lb ft 26 N m 2 6 kgf m 19 lb ft ...

Page 164: ...vot shaft nut 3 Engine mounting bolt lower side 4 Engine mounting nut lower side 5 Engine mounting bolt front side 6 Engine mounting nut front side 7 Engine bracket 8 Engine bracket bolt upper side 9 Engine bracket nut upper side 10 Engine bracket bolt lower side 11 Engine bracket nut lower side 12 TIP Apply the molybdenum disulfide grease on the pivot shaft Pivot shaft nut 85 N m 8 5 kgf m 63 lb ...

Page 165: ...pipe and silencer Refer to ENGINE REMOVAL on page 5 1 Radiator hose 1 Disconnect at cylinder head side Carburetor Refer to CARBURETOR on page 7 3 1 Spark plug 1 2 Engine bracket 2 3 Cylinder head 1 4 Power valve housing 1 5 Push rod 1 6 Cylinder 1 1 2 3 4 5 4 5 6 13 N m 1 3 kgf m 9 6 lb ft 20 N m 2 0 kgf m 15 lb ft 34 N m 3 4 kgf m 25 lb ft 28 N m 2 8 kgf m 21 lb ft 4 5 N m 0 45 kgf m 3 3 lb ft 4 ...

Page 166: ... 1 3 Piston 1 4 Small end bearing 1 5 Piston ring 1 6 Power valve cover 1 7 Thrust plate 1 8 Power valve holder 1 9 Valve shaft 1 10 Collar 2 11 Link lever 1 12 Power valve 1 1 13 Power valve 2 1 1 2 3 4 5 1 6 7 8 9 10 11 12 13 4 0 N m 0 40 kgf m 3 0 lb ft 8 N m 0 8 kgf m 5 9 lb ft 4 0 N m 0 40 kgf m 3 0 lb ft 5 N m 0 5 kgf m 3 7 lb ft 10 ...

Page 167: ... PISTON 1 Remove Piston pin clip 1 TIP Before removing the piston pin clip cover the crankcase opening with a clean rag to prevent the piston pin clip from falling into the crankcase 2 Remove Piston pin 1 Piston 2 Small end bearing NOTICE ECA13810 Do not use a hammer to drive the piston pin out TIP Before removing the piston pin deburr the pis ton pin clip s groove and the piston s pin bore ar ea ...

Page 168: ...cylin der head using a figure eight sanding pat tern TIP To ensure an even surface rotate the cylinder head several times EAM30546 CHECKING THE CYLINDER AND PISTON 1 Check Piston wall Cylinder wall Vertical scratches Replace the cylinder and replace the piston and piston rings as a set 2 Measure Piston to cylinder clearance a Measure the cylinder bore C with the cyl inder bore gauge TIP Measure th...

Page 169: ...the piston that matches the above chart Diameter 53 957 53 972 mm 2 1243 2 1249 in a 17 5 mm 0 69 in from the bottom edge of the piston Piston to cylinder clearance Cylinder bore Piston skirt diameter Piston to cylinder clearance 0 040 0 045 mm 0 0016 0 0018 in Cylinder mark a Cylinder size A 54 000 54 002 mm 2 1260 2 1261 in B 54 004 54 006 mm 2 1261 2 1262 in C 54 008 54 010 mm 2 1263 2 1264 in ...

Page 170: ...discoloration grooves Replace the piston pin and then check the fuel and en gine mixing oil 2 Measure Piston pin outside diameter a Out of specification Replace the piston pin 3 Measure Piston pin bore inside diameter b Out of specification Replace the piston 4 Calculate Piston pin to piston pin bore clearance Out of specification Replace the piston pin and piston as a set Top ring Ring side clear...

Page 171: ...void scratching the aluminum EAM30551 ASSEMBLING THE POWER VALVE 1 Install Power valve 1 1 Power valve 2 2 Bolt power valve 3 TIP Install the power valve at cut away faced a for down side 2 Install Spring 1 Link lever 2 Collar 3 Valve shaft 4 Power valve holder 5 Power valve link lever bolt 6 TIP Install the spring to the link lever and then to the cylinder Install the spring with its stopper port...

Page 172: ...VS breather hose with its opening portion b facing backward EAM30554 INSTALLING THE PISTON AND CYLINDER 1 Install Piston ring 1 TIP Take care not to scratch the piston or damage the piston ring Align the piston ring gap with the pin 2 After installing the piston ring check the smooth movement of it 2 Install Cylinder gasket 1 Small end bearing 2 with the recommended lubricant Dowel pin 3 Thrust pl...

Page 173: ...linder with the recommended lubricant 5 Install Cylinder Cylinder nut 1 TIP While compressing the piston ring with one hand install the cylinder with the other hand Tighten the nuts in stage using a crisscross pattern 6 Install Collar 1 Push rod 2 Plain washer 3 Push rod bolt 4 NOTICE ECA27100 Be sure to use the collar If the collar is not used the power valve constituent parts will result in dama...

Page 174: ...y the lithium soap base grease on the O rings 3 Install Cylinder head 1 Copper washer 2 Cylinder head nut 3 TIP Tighten the cylinder head nut in stage using a crisscross pattern 4 Install Spark plug Spark plug cap Radiator hose Power valve housing bolt 4 0 N m 0 40 kgf m 3 0 lb ft Recommended lubricant Lithium soap based grease New T R New Cylinder head nut 28 N m 2 8 kgf m 21 lb ft Spark plug 20 ...

Page 175: ...GENERAL CHASSIS on page 4 1 Fuel tank Refer to FUEL TANK on page 7 1 Radiator bolt Refer to RADIATOR on page 6 2 CDI magneto lead Disconnect 1 Crankcase cover left 1 2 Rotor nut 1 3 CDI magneto rotor 1 4 Stator 1 5 Woodruff key 1 7 N m 0 7 kgf m 5 2 lb ft 56 N m 5 6 kgf m 41 lb ft 5 N m 0 5 kgf m 3 7 lb ft 1 2 3 4 5 ...

Page 176: ...e a Stator outer surface b Damage Inspect the crankshaft runout and crankshaft bearing If necessary replace CDI magneto and or stator EAM30564 CHECKING THE WOODRUFF KEY 1 Check Woodruff key 1 Damage Replace EAM30565 INSTALLING THE CDI MAGNETO 1 Install Stator 1 Stator coil screw 2 TIP Temporarily tighten the screw at this point 2 Install Woodruff key 1 Rotor 2 TIP Clean the tapered portions of the...

Page 177: ... page 3 26 5 Tighten Stator coil screw 1 6 Check Ignition timing Re check the ignition timing 7 Connect CDI magneto lead 1 Refer to CABLE ROUTING DIAGRAM on page 2 15 8 Install Crankcase cover gasket left Crankcase cover left 1 Crankcase cover screw left 2 TIP Tighten the screws in stage using a crisscross pattern CDI magneto rotor nut 56 N m 5 6 kgf m 41 lb ft Rotor holding tool 90890 01235 Unive...

Page 178: ... 3 6 Bolt brake pedal Shift the brake pedal downward Radiator hose 4 Disconnect at water pump side Push rod bolt Refer to CYLINDER HEAD CYLINDER AND PISTON on page 5 5 1 Kickstarter lever 1 2 Crankcase cover right 1 3 Bolt primary drive gear 1 4 Primary driven gear 1 5 Primary drive gear 1 1 2 3 4 5 10 N m 1 0 kgf m 7 4 lb ft 48 N m 4 8 kgf m 35 lb ft 10 N m 1 0 kgf m 7 4 lb ft ...

Page 179: ...KICKSTARTER 5 19 Removing the kickstarter shaft Order Job Parts to remove Q ty Remarks 1 Kick idle gear 1 2 Kick shaft assembly 1 1 2 ...

Page 180: ...ICK IDLE GEAR 1 Check Kick gear 1 Wear damage Replace the kick shaft as sembly Kick idle gear 2 Gear teeth a Wear damage Replace EAM30104 INSTALLING THE KICK SHAFT ASSEMBLY 1 Install Kick gear 1 Washer 2 Torsion spring 3 to kick shaft 4 TIP Make sure the stopper a of the torsion spring fits into the hole b on the kick shaft 2 Install Spring guide 1 TIP Slide the spring guide into the kick shaft ma...

Page 181: ...Apply the transmission oil on the kick idle gear inner circumference EAM30571 INSTALLING THE PRIMARY DRIVE GEAR 1 Install Spacer 1 Primary drive gear 2 Primary drive gear bolt 3 TIP Install the primary drive gear with its depressed side toward you 2 Install Primary driven gear Refer to CLUTCH on page 5 26 3 Tighten Primary drive gear bolt 1 TIP Place an aluminum plate a between the teeth of the pr...

Page 182: ... 1 Washer 2 Kickstarter lever bolt 3 TIP Install the kickstarter closest to but not contact ing the pillar tube 4 2 Install Shift pedal 1 Shift pedal bolt 2 TIP Align the upper line a of the shift pedal with the center b of the crankcase projection and rotate the shift pedal counterclockwise until it first en gages Then install the shift pedal Crankcase cover screw right 10 N m 1 0 kgf m 7 4 lb ft...

Page 183: ...ase cover right Refer to KICKSTARTER on page 5 18 1 Governor assembly 1 2 Dowel pin 1 3 Retainer 1 4 Ball 4 5 Retainer weight 1 6 Washer 3 7 Bearing 2 8 Collar 1 9 Plate 1 10 Compression spring 1 11 Governor gear 1 12 Governor shaft 1 13 Governor fork 1 1 2 3 4 5 6 7 8 9 10 11 12 5 N m 0 5 kgf m 3 7 lb ft 6 7 6 13 ...

Page 184: ...rust bearing 1 Washer 2 Wear damage Replace EAM30569 INSTALLING THE GOVERNOR 1 Install Governor gear 1 Compression spring 2 Plate 3 Washer 4 Thrust bearing 5 Collar 6 Retainer weight 7 to governor shaft 8 TIP Apply the lithium soap base grease on the thrust bearing 2 Install Ball 1 Retainer 2 to governor shaft 3 TIP Apply the transmission oil on the retainer and ball 1 1 2 1 2 2 Recommended lubric...

Page 185: ...e compressing the spring install the dowel pin Make sure the dowel pin fits into the groove a in the retainer 4 Install Governor assembly 1 TIP Align the groove a in the governor with the fork b and set the governor in the crankcase cover G 1 2 3 1 a ...

Page 186: ...RANSMISSION OIL on page 3 6 Bolt brake pedal Shift the brake pedal downward Rotor and stator Refer to CDI MAGNETO on page 5 15 Clutch cable Disconnect at engine side 1 Clutch cover 1 2 Gasket 1 3 Clutch spring 5 4 Pressure plate 1 5 Friction plate 8 6 Clutch plate 7 1 2 5 3 4 5 6 10 N m 1 0 kgf m 7 4 lb ft 10 N m 1 0 kgf m 7 4 lb ft ...

Page 187: ... Washer 1 4 Bearing 1 5 Ball 1 6 Push rod 2 1 7 Clutch boss nut 1 8 Lock washer 1 9 Clutch boss 1 10 Thrust washer 1 D ø34 mm 1 34 in 11 Primary driven gear 1 12 Bearing 1 13 Spacer 1 1 14 Thrust washer 1 D ø34 mm 1 34 in 15 Push lever shaft 1 1 2 3 4 5 6 7 8 9 10 11 12 14 15 80 N m 8 0 kgf m 59 lb ft 13 ...

Page 188: ...s a set EAM30111 CHECKING THE CLUTCH SPRINGS 1 Check Clutch spring Damage Replace the clutch springs as a set 2 Measure Clutch spring free length Out of specification Replace the clutch springs as a set EAM30112 CHECKING THE CLUTCH HOUSING 1 Check Clutch housing dogs Damage pitting wear Deburr the clutch housing dogs or replace the clutch housing TIP Pitting on the clutch housing dogs will cause e...

Page 189: ...ear Damage wear Replace the primary drive and primary driven gears as a set Excessive noise during operation Replace the primary drive and primary driven 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 set EAM30118 CHECKING THE PRIMARY DRIVEN GEAR 1 Check Primary driven gear Damage wear Replace the ...

Page 190: ...ersal clutch holder 3 to hold the clutch boss 5 Bend the lock washer 1 tab 6 Install Friction plate 1 Clutch plate 2 TIP Install the clutch plates and friction plates alter nately on the clutch boss starting with a friction plate and ending with a friction plate Apply the transmission oil on the friction plates and clutch plates 7 Install Bearing 1 Washer 2 Circlip 3 to push rod 1 4 Clutch boss nu...

Page 191: ...ng Clutch spring bolt TIP Tighten the bolts in stage using a crisscross pat tern 11 Install Dowel pin 1 Gasket clutch cover 2 12 Install Clutch cover Clutch cover bolt TIP Tighten the bolts in stage using a crisscross pat tern 13 Install O ring 1 Clutch cable 2 TIP Apply the lithium soap base grease on the O ring Clutch spring bolt 10 N m 1 0 kgf m 7 4 lb ft G 3 2 1 4 T R Clutch cover bolt 10 N m ...

Page 192: ...r Order Job Parts to remove Q ty Remarks 1 Shift pedal 1 2 Shift shaft 1 3 Segment bolt 1 4 Roller 1 5 Shift guide 1 6 Shift lever assembly 1 7 Stopper lever 1 1 2 4 5 3 6 7 10 N m 1 0 kgf m 7 4 lb ft 30 N m 3 0 kgf m 22 lb ft 10 N m 1 0 kgf m 7 4 lb ft 12 N m 1 2 kgf m 8 9 lb ft ...

Page 193: ...amage wear Replace 2 Check Shift guide 1 Shift lever 2 Pawl 3 Pawl pin 4 Spring 5 Wear damage Replace EAM30127 CHECKING THE STOPPER LEVER 1 Check Stopper lever 1 Wear damage Replace Roller 2 Rotate outer race with a finger Rough spot seizure Replace the stopper lever Torsion spring 3 Broken Replace EAM30131 INSTALLING THE SHIFT SHAFT 1 Install Torsion spring 1 Holder 2 Holder bolt 3 Washer 4 Stopp...

Page 194: ...Spring 1 Pawl pin 2 Pawl 3 to the shift lever TIP Apply the transmission oil on the spring pawl pin and pawl 4 Install Shift lever assembly to the shift guide 5 Install Shift lever assembly 1 Shift guide 2 TIP The shift lever assembly is installed at the same time as the shift guide Apply the transmission oil on the segment bolt shaft 6 Tighten Shift guide bolt 1 7 Install Roller 1 Shift shaft 2 S...

Page 195: ...8 Install Shift pedal 1 Shift pedal bolt 2 TIP Align the upper line a of the shift pedal with the center b of the crankcase projection and rotate the shift pedal counterclockwise until it first en gages Then install the shift pedal Shift pedal bolt 12 N m 1 2 kgf m 8 9 lb ft T R ...

Page 196: ...Stopper lever Refer to SHIFT SHAFT on page 5 32 Rotor and stator Refer to CDI MAGNETO on page 5 15 1 Segment 1 2 Crankcase bolt 6 L 45 mm 1 77 in 3 Crankcase bolt 4 L 55 mm 2 17 in 4 Crankcase bolt 1 L 65 mm 2 56 in 5 Crankcase bolt 1 L 75 mm 2 95 in 6 Holder 1 7 Crankcase right 1 8 Crankcase left 1 9 Oil seal 2 10 Bearing 2 1 6 7 8 9 10 2 3 4 5 3 3 3 2 2 2 2 2 10 9 10 N m 1 0 kgf m 7 4 lb ft 30 N...

Page 197: ...not separate check for a remaining case bolt or fitting Do not force 2 Remove Bearing 1 TIP Remove the bearing from the crankcase by pressing its inner race Do not use the removed bearing EAM30150 CHECKING THE CRANKCASE 1 Wash Crankcase TIP Wash the crankcase in a mild solvent Remove any remaining gasket from the crank case mating surface 2 Check Crankcase Crack damage Replace Oil delivery passage...

Page 198: ...laced on top of each other If you use the washers in the installation install the washers so that they do not deviate from the crankshaft center When installing the crankcase the connecting rod should be positioned at TDC top dead center Make sure that the dowel pin is in place 6 Install Holder 1 Holder bolt 2 Yamaha bond No 1215 90890 85505 Three bond No 1215 1 2 1 2 mm 0 04 0 08 in 1 2 mm 0 04 0...

Page 199: ...CRANKCASE 5 39 7 Install Clamp 1 Crankcase bolt 2 TIP Tighten the crankcase bolts in stage using a crisscross pattern Crankcase bolt 14 N m 1 4 kgf m 10 lb ft LT 1 2T R ...

Page 200: ...T 5 40 EAM20193 CRANKSHAFT Removing the crankshaft assembly Order Job Parts to remove Q ty Remarks Engine Refer to ENGINE REMOVAL on page 5 1 Crankcase Separate 1 Crankshaft 1 2 Oil seal 2 3 Bearing 2 1 3 3 2 2 ...

Page 201: ...nstaller bolt 3 and adapter M12 4 NOTICE ECA26470 In order to prevent the crankshaft seizure apply molybdenum disulfide grease NOTICE ECA23810 Do not use a hammer to drive in the crank shaft TIP 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 a...

Page 202: ...CRANKSHAFT 5 42 seal lip 4 1 2 3 M ...

Page 203: ...move Q ty Remarks Engine Refer to ENGINE REMOVAL on page 5 1 Crankcase Refer to CRANKCASE on page 5 36 1 Guide bar long 1 2 Guide bar short 1 3 Shift cam 1 4 Shift fork 3 R 1 5 Shift fork 1 L 1 6 Shift fork 2 C 1 7 Main axle 1 8 Drive axle 1 9 Collar 1 1 2 3 4 5 6 7 8 9 10 N m 1 0 kgf m 7 4 lb ft 10 N m 1 0 kgf m 7 4 lb ft ...

Page 204: ...or a malfunctioning shift fork replace not only the shift fork itself but the two gears each adja cent to the shift fork EAM30155 CHECKING THE SHIFT DRUM ASSEMBLY 1 Check Shift drum groove Damage scratches wear Replace the shift drum assembly Shift drum segment Damage wear Replace the shift drum as sembly EAM30156 CHECKING THE TRANSMISSION 1 Measure Main axle runout with a centering device and dia...

Page 205: ... the in ner surface of the sliding gear then install 2 Install 2nd wheel gear 29T 1 5th wheel gear 24T 2 3rd wheel gear 27T 3 4th wheel gear 23T 4 6th wheel gear 23T 5 1st wheel gear 31T 6 to drive axle 7 TIP Apply the molybdenum disulfide oil on the in ner and end surface of the idler gear and on the inner surface of the sliding gear then install Apply the molybdenum disulfide grease on the inner...

Page 206: ...rive axle Mesh the shift fork 2 C with the 3rd 4th pinion gear 5 on the main axle 6 Install Shift cam 1 TIP Apply the transmission oil on the shift cam Install the shift cam while holding up the 5th wheel gear 2 and keeping the shift fork 1 3 moved in the direction of the arrow 7 Install Guide bar short 1 Guide bar long 2 TIP Apply the transmission oil on the guide bars Be sure the long bar is ins...

Page 207: ... 10 COOLING SYSTEM COOLING SYSTEM DIAGRAMS 6 1 RADIATOR 6 2 CHECKING THE RADIATOR 6 3 INSTALLING THE RADIATOR 6 3 WATER PUMP 6 5 DISASSEMBLING THE WATER PUMP 6 6 CHECKING THE WATER PUMP 6 6 ASSEMBLING THE WATER PUMP 6 6 ...

Page 208: ...COOLING SYSTEM DIAGRAMS 6 1 EAM20186 COOLING SYSTEM DIAGRAMS 1 Radiator hose 1 2 Radiator right 3 Radiator hose 4 4 Water pump 5 Radiator left ...

Page 209: ...r to FUEL TANK on page 7 1 1 Radiator guard 2 2 Radiator hose clamp radiator hose 1 3 2 Only loosening 3 Radiator hose 2 1 4 Radiator left 1 5 Radiator hose 4 1 6 Radiator right 1 7 Radiator hose 1 1 8 Radiator hose 3 1 9 Radiator breather hose 1 1 2 3 4 5 6 7 8 9 1 5 N m 0 15 kgf m 1 1 lb ft 10 N m 1 0 kgf m 7 4 lb ft 1 5 N m 0 15 kgf m 1 1 lb ft 10 N m 1 0 kgf m 7 4 lb ft 10 N m 1 0 kgf m 7 4 lb...

Page 210: ...ck Radiator cap valve opening pressure a Install the radiator cap tester adapter 2 and the radiator cap tester 1 to the radi ator cap 3 and activate the tester to check whether it can stay for 5 to 10 sec onds within standard pressure values TIP Before attaching the cap to the tester apply wa ter to its sealing surface No stay Replace EAM30506 INSTALLING THE RADIATOR 1 Fill Cooling system with the...

Page 211: ...warm up Make sure that coolant is filled up to the up per level beforehand 5 Check Pressure value No stay for 5 to 10 seconds at the test pres sure value Correct Radiator Radiator hose connections Coolant leaks Correct or replace Radiator hose Bulges Replace WARNING EWA19090 When the radiator cap tester is removed coolant will spout therefore cover it with a cloth beforehand Test pressure value 12...

Page 212: ...Remarks Crankcase cover right Refer to KICKSTARTER on page 5 18 1 Water pump housing cover 1 2 Impeller shaft gear 1 3 Dowel pin 1 4 Washer 1 5 Impeller shaft assembly 1 6 Bearing 1 7 Oil seal 2 10 N m 1 0 kgf m 7 4 lb ft 10 N m 1 0 kgf m 7 4 lb ft 10 N m 1 0 kgf m 7 4 lb ft 1 2 3 4 5 6 7 7 ...

Page 213: ...62 ASSEMBLING THE WATER PUMP 1 Install Oil seal 1 2 TIP Apply the lithium soap based grease on the oil seal lip Install the oil seal with its manufacture s marks or numbers facing the crankcase cover right 3 2 Install Bearing 1 TIP Install the bearing by pressing its outer race par allel 3 Install Impeller shaft 1 TIP Take care so that the oil seal lip is not dam aged or the spring does not slip o...

Page 214: ...dowel pin fitted in the groove a in the same gear 5 Install Dowel pin 1 Gasket 2 6 Install Water pump housing 1 Water pump housing cover bolt 2 Copper washer 3 Coolant drain bolt 4 Water pump housing cover bolt 10 N m 1 0 kgf m 7 4 lb ft Coolant drain bolt 10 N m 1 0 kgf m 7 4 lb ft New New T R New T R ...

Page 215: ...K 7 1 AIR FILTER 7 2 CARBURETOR 7 3 HANDLING NOTE 7 5 CHECKING THE CARBURETOR 7 5 CHECKING THE REED VALVE 7 6 INSTALLING THE REED VALVE 7 7 ASSEMBLING THE CARBURETOR 7 7 INSTALLING THE CARBURETOR 7 9 MEASURING AND ADJUSTING THE FUEL LEVEL 7 10 ...

Page 216: ... to GENERAL CHASSIS on page 4 1 Side cover left right Air scoop left right 1 Fitting band 1 2 Fuel cock assembly 1 3 O ring 1 4 Fuel tank 1 5 Fuel tank breather hose 2 6 Valve joint 1 10 N m 1 0 kgf m 7 4 lb ft 7 N m 0 7 kgf m 5 2 lb ft 4 0 N m 0 40 kgf m 3 0 lb ft 7 N m 0 7 kgf m 5 2 lb ft 2 1 4 5 6 4 2 3 ...

Page 217: ...eat Refer to GENERAL CHASSIS on page 4 1 1 Fitting bolt 1 2 Air filter element 1 3 Air filter guide 1 4 Guide holder 1 5 Band 1 6 Spacer 1 7 Air filter joint 1 8 Air filter case 1 2 3 4 5 6 7 3 3 1 8 8 N m 0 8 kgf m 5 9 lb ft 2 0 N m 0 20 kgf m 1 5 lb ft 8 N m 0 8 kgf m 5 9 lb ft 3 5 N m 0 35 kgf m 2 6 lb ft ...

Page 218: ...y Remarks Fuel tank Refer to FUEL TANK on page 7 1 1 Carburetor joint clamp 2 2 Carburetor 1 3 Carburetor joint 1 4 Reed valve assembly 1 5 Reed valve stopper 2 6 Reed valve 2 1 2 3 4 5 6 2 3 N m 0 23 kgf m 1 7 lb ft 10 N m 1 0 kgf m 7 4 lb ft 1 0 N m 0 10 kgf m 0 73 lb ft 2 3 N m 0 23 kgf m 1 7 lb ft 1 ...

Page 219: ...Throttle valve 1 3 Needle holder 1 4 Jet needle 1 5 Float chamber 1 6 Needle jet cover 1 7 Float pin 1 8 Float 1 9 Valve seat 1 10 Main jet 1 11 Main jet holder 1 12 Pilot jet 1 13 Starter plunger 1 14 Throttle stop screw 1 15 Pilot air screw 1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 4 0 N m 0 40 kgf m 3 0 lb ft ...

Page 220: ...e a petroleum based solvent for cleaning Blow out all passages and jets with com pressed air Never use a wire When cleaning the main air passage blow air through it while covering the nozzle with a clean rag 3 Check Fuel passages Obstruction Clean a Wash the carburetor in a petroleum based solvent Do not use any caustic carburetor cleaning solution b Blow out all of the passages and jets with comp...

Page 221: ...he carbu retor Do not remove the filter except when re placing it 11 Check Free movement Stick Repair or replace TIP Insert the throttle valve 1 into the carburetor body and check for free movement 12 Check Hose joints Cracks damage Replace 13 Check Carburetor breather hoses Fuel hoses Cracks damage wear Replace Obstruction Clean Blow out the hoses with compressed air EAM30574 CHECKING THE REED VA...

Page 222: ...avoid warping 2 Install Reed valve assembly 1 Reed valve spacer 2 3 Install Carburetor joint 1 Carburetor joint bolt 2 EAM30576 ASSEMBLING THE CARBURETOR 1 Install Throttle stop screw 1 Locknut 2 Pilot air screw 3 a Turn in the pilot air screw until it is lightly seated b Turn out the pilot air screw by the number of turns recorded before removing Valve stopper height 8 2 8 6 mm 0 32 0 34 in Reed ...

Page 223: ...g the needle valve to the float in stall them to the carburetor Check the float for smooth movement 5 Install Float chamber 1 Plate 2 Screw float chamber 3 6 Install Jet needle 1 Needle holder 2 to throttle valve 3 7 Install Throttle cable 1 Locknut 2 Mixing chamber top 3 Spring throttle valve 4 Ring 5 Throttle valve 6 TIP While compressing the spring connect the Locknut throttle cable carburetor ...

Page 224: ... Refer to CABLE ROUTING DIAGRAM on page 2 15 TIP Pass the air vent hose at the rear on the air cleaner side of the throttle cable 4 EAM30578 INSTALLING THE CARBURETOR 1 Install Carburetor 1 TIP Install the projection between the carburetor joint slots 2 Tighten Air filter case joint clamp 1 Carburetor joint clamp 2 3 Clamp Air vent hose 1 Overflow hose 2 Refer to CABLE ROUTING DIAGRAM on page 2 15...

Page 225: ...re the fuel level with the fuel level gauge TIP Keep the carburetor and fuel level gauge verti cally when measuring the fuel level e If the fuel level is not within specification inspect the valve seat and needle valve f If either is worn replace them both g If both are fine adjust the fuel level by bending the float tab b on the float h Recheck the fuel level Fuel level using fuel level gauge 9 5...

Page 226: ...CARBURETOR 7 11 ...

Page 227: ...LOR CODE 8 1 IGNITION SYSTEM 8 2 TROUBLESHOOTING 8 2 ELECTRICAL COMPONENTS 8 3 CHECKING THE SWITCHES 8 4 CHECKING THE IGNITION SPARK GAP 8 6 CHECKING THE SPARK PLUG CAP 8 6 CHECKING THE IGNITION COIL 8 6 CHECKING THE PICKUP COIL 8 7 CHECKING THE SOURCE COIL 8 7 ...

Page 228: ...5 WIRING DIAGRAM EAM30608 COLOR CODE 1 Engine stop switch 2 CDI unit 3 Ignition coil 4 CDI magneto 5 Spark plug B Black O Orange Y Yellow B R Black Red B W Black White G L Green Blue G W Green White W L White Blue W R White Red ...

Page 229: ...cap Refer to CHECKING THE SPARK PLUG CAP on page 8 6 NG Replace the spark plug cap OK 4 Check the ignition coil Refer to CHECKING THE IGNI TION COIL on page 8 6 NG Replace the ignition coil OK 5 Check the engine stop switch Refer to CHECKING THE SWITCHES on page 8 4 NG Replace the engine stop switch OK 6 Check the pickup coil Refer to CHECKING THE PICKUP COIL on page 8 7 NG Replace the pickup coil...

Page 230: ...ELECTRICAL COMPONENTS 8 3 EAM20147 ELECTRICAL COMPONENTS 1 2 3 1 Engine stop switch 2 CDI unit 3 Ignition coil ...

Page 231: ...ELECTRICAL COMPONENTS 8 4 EAM30289 CHECKING THE SWITCHES 1 1 Engine stop switch ...

Page 232: ...hecking for continuity switch back and forth between the switch positions a few times Terminal connections of the switch are shown in the terminal connection diagram below The switch positions a are shown in the far left column and the switch lead colors are shown in the top row in the switch illustration TIP indicates continuity between switch terminals i e a closed circuit at each switch positio...

Page 233: ... specification Replace a Connect the digital circuit tester to the spark plug cap b Measure the spark plug cap resistance EAM30296 CHECKING THE IGNITION COIL 1 Check Primary coil resistance Out of specification Replace a Disconnect the ignition coil connectors from the ignition coil terminals b Connect the digital circuit tester to the ignition coil as shown Minimum ignition spark gap 6 0 mm 0 24 ...

Page 234: ... the wire harness 2 Check Charging coil 1 resistance B R G W Out of specification Replace the CDI mag neto a Connect the digital circuit tester to the CDI magneto coupler as shown Secondary coil resistance 5 68 8 52 k Digital circuit tester CD732 90890 03243 Model 88 Multimeter with tachom eter YU A1927 Positive tester probe High tension cord 1 Negative tester probe Yellow 2 Pickup coil resistance...

Page 235: ...on Replace the CDI mag neto a Connect the digital circuit tester to the CDI magneto coupler as shown b Measure the source coil resistance G L B Charging coil 2 resistance 44 0 66 0 Digital circuit tester CD732 90890 03243 Model 88 Multimeter with tachom eter YU A1927 Positive tester probe Green Blue 1 Negative tester probe Black 2 ...

Page 236: ...ELECTRICAL COMPONENTS 8 9 ...

Page 237: ...NERAL INFORMATION 9 1 TROUBLESHOOTING OF ENGINE 9 1 TROUBLESHOOTING OF CLUTCH 9 6 TROUBLESHOOTING OF TRANSMISSION 9 7 TROUBLESHOOTING OF COOLING SYSTEM 9 8 TROUBLESHOOTING OF BRAKE 9 9 TROUBLESHOOTING OF SUSPENSION 9 9 TROUBLESHOOTING OF STEERING HANDLING 9 11 ...

Page 238: ...el not supplied Empty fuel tank Fill the fuel tank with fuel Clogged fuel tank cap breather hole Clean the fuel tank cap Clogged or damaged fuel hose Clean repair or replace the fuel hose Fuel leakage Check the fuel passage Repair or replace as necessary Clogged fuel cock strainer Clean or replace the fuel cock strainer Clogged fuel cock Clean or replace the fuel cock Cracked damaged or worn fuel ...

Page 239: ...g cap Defective ignition coil Replace the ignition coil CDI unit failure Replace the CDI unit Fuel not supplied Fuel leakage Check the fuel passage Repair or replace as necessary Clogged carburetor fuel passage Clean the carburetor Clogged needle valve or needle valve seat Clean the needle valve or needle valve seat Damaged float Replace the float Water or foreign material in fuel degraded fuel Ch...

Page 240: ... hose Replace the vacuum hose Damaged carburetor joint Replace the carburetor joint Loose carburetor joint Tighten the carburetor joint bolts to the specified torque Clogged air filter element Clean or replace the air filter ele ment Symptom Possible cause Actions Spark plug does not produce a spark Incorrect spark plug gap Adjust the spark plug gap Worn or damaged spark plug Replace the spark plu...

Page 241: ...ghten the main jet to the speci fied torque Bent damaged or worn jet needle Replace the jet needle Cracks or damage in the piston valve diaphragm Replace the piston valve dia phragm Problem with piston valve move ment movement is not smooth Replace the piston valve Damaged or worn needle valve seat Replace the needle valve seat Loose needle valve seat Tighten the needle valve seat to the specified...

Page 242: ...n rings as a set Worn or damaged piston Replace the piston and piston rings as a set Worn piston piston pin hole Replace the piston and piston pin as a set Worn or damaged piston pin Replace the piston pin Worn or damaged cylinder bore Replace the cylinder piston and piston rings as a set Carbon buildup in piston head and combustion chamber Clean the piston head and com bustion chamber Noise heard...

Page 243: ...ine oil Deteriorated oil Change to recommended engine oil Clutch drags Faulty clutch spring Replace the clutch springs as a set Warped pressure plate Replace the pressure plate Swollen friction plate Replace the friction plates as a set Warped clutch plate Replace the clutch plates as a set Bent pull rod outer pull type Replace the pull rod Worn pull rod tooth outer pull type Replace the pull rod ...

Page 244: ...e the shift drum Seized shift fork Replace the shift fork and shift fork guide bar as a set Bent shift fork guide bar Replace the shift fork guide bar Foreign object between transmis sion gears Remove foreign object from trans mission gears Seized transmission gear Replace the seized gear and the axle as a set Improperly assembled transmis sion Reassemble the transmission axle assembly Jumps out o...

Page 245: ...e the radiator Damaged or faulty water pump Replace the water pump Damaged hoses or pipes Replace the hose or pipe Improperly connected hoses or pipes Connect the hoses and pipes properly Clogged air filter element Clean or replace the air filter ele ment Brake drags Check the brake system and repair or replace faulty parts as necessary Incorrect spark plug gap Adjust to the specified spark plug g...

Page 246: ... Damaged brake hose and brake pipe Replace the brake hose and brake pipe Oil or grease on the brake disc or brake pad Clean the brake disc or brake pad Insufficient lubrication of brake lever or brake pedal pivot Lubricate the brake lever or brake pedal pivot Symptom Possible cause Actions Front fork is hard Bent or damaged inner tube Replace the inner tube Bent or damaged outer tube Replace the o...

Page 247: ...mper rod assembly bolt Tighten the damper rod assembly bolt to the specified torque Damaged damper rod assembly bolt copper washer Replace the damper rod assembly bolt copper washer Cracked or damaged cap bolt O ring Replace the cap bolt O ring Rear suspension is hard Bent or damaged rear shock absorber rod Replace the rear shock absorber Bent swingarm pivot shaft Replace the swingarm pivot shaft ...

Page 248: ... shock absorber rod Replace the rear shock absorber Damaged oil seal lip Replace the rear shock absorber Symptom Possible cause Actions Handlebar wobble Loose steering ring nut Tighten the steering ring nut to the specified torque Worn bearing or bearing race Replace the bearing and bearing race as a set Warped front fork Repair or replace the front fork Bent front wheel axle Replace the front whe...

Page 249: ...que Incorrect front fork oil level Adjust to the specified front fork oil level Rear wheel vibration Incorrect wheel balance Adjust the wheel balance Loose spoke Tighten the spoke and adjust the runout Damaged or worn wheel bearing Replace the wheel bearing Worn deformed or incorrect tire Replace the tire Loose wheel axle nut Tighten the wheel axle nut to the specified torque Loose swingarm pivot ...

Page 250: ...TROUBLESHOOTING 9 13 ...

Page 251: ...R SETTING 10 5 SPECIFICATIONS OF JET NEEDLE 10 5 EXAMPLES OF CARBURETOR SETTING DEPENDING ON SYMPTOM 10 5 CHANGE OF THE HEAT RANGE OF SPARK PLUGS 10 7 CHASSIS 10 8 SELECTION OF THE SECONDARY REDUCTION RATIO SPROCKET 10 8 DRIVE AND REAR WHEEL SPROCKETS SETTING PARTS 10 8 TIRE PRESSURE 10 8 FRONT FORK SETTING 10 9 CHANGE IN AMOUNT AND CHARACTERISTICS OF FORK OIL 10 9 SETTING OF SPRING AFTER REPLACEM...

Page 252: ...le to make a note of settings atmo spheric conditions road surface condition lap time etc so that the memorandum can be used as a reference useful for future EAM30591 ATMOSPHERIC CONDITIONS AND CARBURETOR SETTINGS The air density i e concentration of oxygen in the air determines the richness or leanness of the air fuel mixture Therefore refer to the above table for mixture settings That is Higher ...

Page 253: ... 4 open can be set by turning the pilot air screw 1 Turning in the pilot air screw will make the mix ture enrich at low speeds and turning it out will lean it EAM30596 PILOT JET ADJUSTMENT The richness of air fuel mixture with the throttle fully closed to 1 2 open can be set by turning the pilot jet 1 It is changed when adjustment can not be made by the pilot air screw alone A larger size jet resu...

Page 254: ...iate speeds Rough engine operation is felt and the engine will not pick up speed smoothly In this case step up the jet needle clip by one groove or 0 5 groove and move down the needle to lean out the mixture 2 Too lean at intermediate speeds The engine breathes hard and will not pick up speed quickly In this case step down the jet needle clip by one groove or 0 5 groove and move up the needle to e...

Page 255: ... Pilot jet Rich 50 4KM 14142 50 47 5 4KM 14142 47 45 4KM 14142 45 42 5 4KM 14142 42 STD 40 4KM 14142 40 37 5 4KM 14142 37 35 4KM 14142 35 32 5 4KM 14142 32 Lean 30 4KM 14142 30 Throttle valve Rich STD 4 0 1C3 14112 40 Lean 4 25 1C3 14112 42 Jet needle Rich 6BFY44 72 284 14116 K2 6BFY44 73 284 14116 K3 6BFY44 74 284 14116 K4 6BFY44 75 284 14116 K5 Lean 6BFY44 76 284 14116 K6 Rich 6BFY43 72 284 1411...

Page 256: ...43 73 4 6BFY43 74 4 6BFY43 75 4 6BFY43 76 4 0 5 richer 6BFY44 72 3 6BFY44 73 3 6BFY44 74 3 6BFY44 75 3 6BFY44 76 3 6BFY42 72 4 6BFY42 73 4 6BFY42 74 4 6BFY42 75 4 6BFY42 76 4 STD 6BFY43 72 3 6BFY43 73 3 6BFY43 74 3 6BFY43 75 3 6BFY43 76 3 0 5 leaner 6BFY44 72 2 6BFY44 73 2 6BFY44 74 2 6BFY44 75 2 6BFY44 76 2 6BFY42 72 3 6BFY42 73 3 6BFY42 74 3 6BFY42 75 3 6BFY42 76 3 Lean 1 leaner 6BFY43 72 2 6BFY...

Page 257: ... clip position is the jet needle groove on which the clip is installed The positions are numbered from the top It a change in the clip position 1 groove is effective try another jet needle that provides a difference of 0 5 in the clip position Closed to 1 4 throttle Hard breathing Speed down Use jet needle having a smaller diam eter Closed to 1 4 throttle Poor acceleration White smoke Use jet need...

Page 258: ... No of the main jet must be changed by 30 it is advisable to change the heat range of spark plugs and newly select the proper main jet TIP When checking the discoloration of spark plugs be sure to stop the engine immediately after a run and check Avoid racing When changing the heat range of spark plugs never attempt to change it more than 1 rank When using a spark plug other than standard check it...

Page 259: ...an develop its maximum revolutions toward the end of the straight line with care taken to avoid the en gine over revving TIP Riding technique varies from rider to rider and the performance of a machine also vary from machine to machine Therefore do not imitate other rider s settings from the beginning but choose your own setting according to the level of your riding technique EAM30169 DRIVE AND RE...

Page 260: ...cs to have a ten dency to be stiffer with the consequent dete riorated performance and characteristics Therefore adjust the front fork within the specified range EAM30173 SETTING OF SPRING AFTER REPLACEMENT As the front fork setting can be easily affected by the rear suspension take care so that the front and the rear are balanced in position etc when setting the front fork 1 Use of soft spring Ch...

Page 261: ...force EAM30176 CHOOSING SET LENGTH 1 Place a stand or a block under the engine to put the rear wheel above the floor and mea sure the length a between the rear wheel axle center and the rear fender holding bolt 2 Remove the stand or block from the engine and with a rider astride the seat measure the sunken length b between the rear wheel axle center and the rear fender holding bolt 3 Loosen the lo...

Page 262: ...For correction adjust to decrease compression damping force WARNING EWA19200 When using a rear shock absorber other than currently installed use the one whose overall length a does not exceed the stan dard as it may result in faulty performance Never use one whose overall length is great er than standard EAM30178 REAR SHOCK ABSORBER SETTING PARTS Rear shock spring 1 Equal pitch steel spring Unequa...

Page 263: ...THE REAR SHOCK ABSORBER AS SEMBLY on page 3 21 Spring preload adjusting positions Minimum Position in which the spring is turned in 1 5 mm 0 06 in from its free length Standard Position in which the spring is turned in 6 0 mm 0 24 in from its free length Maximum Position in which the spring is turned in 18 0 mm 0 71 in from its free length ...

Page 264: ...noticeable scars etc If any replace affected parts Slide metal Replace with a new one for extended use Piston metal Replace with a new one for extended use Lower bracket tightening torque Retighten to specified torque Poor initial move ment Rebound damp ing force Turn adjuster counterclockwise about 2 clicks to decrease damping Oil seals Apply grease in oil seal wall Soft over entire range bottomi...

Page 265: ...mount Increase oil amount by about 5 cm 0 2 US oz 0 2 Imp oz Obtrusive front tending to upper front posture Compression damping force Turn adjuster counterclockwise about 2 clicks to decrease damping Balance with rear end Set sunken length for 90 95 mm 3 5 3 7 in when one passenger is astride seat upper rear pos ture Spring Replace with soft spring Oil amount Decrease oil amount by about 5 10 cm 0...

Page 266: ... senger is astride seat Spring Replace with soft spring Bottoming out High compres sion damping Turn adjuster clockwise about 1 6 turn to increase damping Spring set length Set sunken length for 90 100 mm 3 5 3 9 in when one pas senger is astride seat Spring Replace with stiff spring Bouncing Rebound damp ing force Turn adjuster clockwise about 2 clicks to increase damping Spring Replace with soft...

Page 267: ...ance Buy with confidence knowing your Genuine Yamaha Accessories will fit right and perform right right out of the box Yamalube Take care of your Yamaha with legendary Yamalube oils lubricants and care products They re formulated and approved by the toughest judges we know the Yamaha engineering teams that know your Yamaha from the inside out Genuine Yamaha Service Manuals Get the same factory man...

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