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EB000000 SR125 SERVICE MANUAL 1996 by Yamaha Motor Co., Ltd. 1st Edition, September 1996 All rights reserved. Any reprinting or unauthorized use without the written permission of Yamaha Motor Co., Ltd. is expressly prohibited.
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It is not possible to include all the knowledge of a mechanic in one manual, so it is assumed that anyone who uses this book to perform maintenance and repairs on Yamaha mo- torcycle has a basic understanding of the mechanical ideas and the procedures of motorcycle repair.
YP002000 HOW TO USE THIS MANUAL MANUAL ORGANIZATION This manual consists of chapters for the main categories of subjects. (See “Illustrated symbols”) 1st title 1 : This is the title of the chapter with its symbol on the upper right corner of each page. 2nd title 2 : This title indicates the section of the chapter and only appears on the first page of each section.
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EB003000 ILLUSTRATED SYMBOLS Illustrated symbols 1 to 9 are designed as SPEC thumb tabs to indicate the chapter’s number INFO and content. 1 General information 2 Specifications INSP 3 Periodic inspection and adjustment 4 Engine 5 Carburation 6 Chassis CARB CHAS 7 Electrical 8 Troubleshooting...
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INDEX GENERAL INFORMATION INFO SPECIFICATIONS SPEC PERIODIC INSPECTION AND INSP ADJUSTMENT ENGINE OVERHAUL CARBURATION CARB CHASSIS CHAS ELECTRICAL ELEC TROUBLESHOOTING TRBL SHTG...
MOTORCYCLE IDENTIFICATION INFO YP100000 GENERAL INFORMATION MOTORCYCLE IDENTIFICATION SR100020 FRAME SERIAL NUMBER The frame serial number 1 is stamped into the right side of the frame. EB100030 ENGINE SERIAL NUMBER The engine serial number 1 is stamped into the crankcase. NOTE: Designs and specifications are subject to change without notice.
6. Keep all parts away from any source of fire. NB101010 REPLACEMENT PARTS 1. Use only genuine Yamaha parts for all re- placements. Use oil and grease recom- mended by Yamaha for all lubrication jobs. Other brands may be similar in function and appearance, but inferior in quality.
IMPORTANT INFORMATION INFO EB101030 LOCK WASHERS/PLATES AND COTTER PINS 1. Replace all lock washers/plates and cotter pins after removal. Bend lock tabs along the bolt or nut flats after the bolt or nut has been tightened to specification. EB101040 BEARINGS AND OIL SEALS Install bearings and oil seals so that the manufacturer’s marks or numbers are visible.
CHECKING OF CONNECTIONS INFO EB801000 CHECKING OF CONNECTIONS Dealing with stains, rust, moisture, etc. on the connector. 1. Disconnect: : Connector 2. Dry each terminal with an air blower. 3. Connect and disconnect the connector two or three. 4. Pull the lead to check that it will not come off. 5.
HOW TO USE THE CONVERSION TABLE INFO EB201000 HOW TO USE THE CONVERSION TABLE All specification data in this manual are listed in Sl and METRIC UNITS. Use this table to convert METRIC unit data to IMPERIAL unit data. METRIC MULTIPLIER ** mm 0.03937 ** in...
SPECIAL TOOLS INFO EB102000 SPECIAL TOOLS The following special tools are necessary for complete and accurate tune-up and assembly. Use only the appropriate special tools; this will help prevent damage caused by the use of inappropriate tools or improvised techniques. When placing an order, refer to the list provided below to avoid any mistakes.
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SPECIAL TOOLS INFO Tool No. Tool name/Usage Illustration 90890-03079 Thickness gauge This tool is used to measure the valve clearance. 90890-03081 Compression gauge 90890-04082 Adaptor These tools are used to measure the engine compression. 90890-03112 Pocket tester These instruments are invaluable for checking the electrical system.
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This tool is used for removing and installing the lifter and for lapping the valve. 90890-06754 Ignition checker This instrument is necessary for checking the ignition system components. 90890-85505 Yamaha bond No.1215 This sealant (bond) is used for crankcase mating surface, etc.
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CHAPTER 2. SPECIFICATIONS GENERAL SPECIFICATIONS ........MAINTENANCE SPECIFICATIONS .
SPEC GENERAL SPECIFICATIONS SPECIFICATIONS GENERAL SPECIFICATIONS Model SR125 Model code: 3MW6 Dimensions: Overall length 1,915 mm Overall width 775 mm Overall height 1,080 mm Seat height 745 mm Wheelbase 1,280 mm Minimum ground clearance 155 mm Minimum turning radius 2,100 mm Basic weight: With oil and full fuel tank 113 kg...
SPEC GENERAL SPECIFICATIONS Model SR125 Carburetor: Type/quantity Y24P/1 Manufacturer TEIKEI Spark plug: Type DR8EA Manufacturer 0.6 X 0.7 mm Spark plug gap Clutch type: Wet, multiple-disc Transmission: Primary reduction system Spur gear Primary reduction ratio 73/22 (3.318) Secondary reduction system Chain drive Secondary reduction ratio 49/14 (3.500)
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SPEC GENERAL SPECIFICATIONS Model SR125 Brake: Front brake type Single disc brake operation Right hand operation Rear brake type Drum brake operation Right foot operation Suspension: Front suspension Telescopic fork Rear suspension Swingarm Shock absorber: Front shock absorber Coil spring/Oil damper Rear shock absorber Coil spring/Oil damper Wheel travel:...
SPEC MAINTENANCE SPECIFICATIONS MAINTENANCE SPECIFICATIONS ENGINE Item Standard Limit Cylinder head: Warp limit 0.03 mm Cylinder: 57.00 X 57.02 mm Bore size 57.1 mm Taper limit 0.05 mm Out of round limit 0.01 mm Camshaft: Cam dimensions 36.537 X 36.637 mm Intake “A”...
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SPEC MAINTENANCE SPECIFICATIONS Item Standard Limit 6.000 X 6.012 mm Guide inside diameter 6.042 mm 6.000 X 6.012 mm 6.042 mm 0.010 X 0.037 mm Stem-to-guide clearance 0.08 mm 0.025 X 0.052 mm 0.10 mm Stem runout limit 0.03 mm 0.9 X 1.1 mm Valve seat width 1.6 mm...
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SPEC MAINTENANCE SPECIFICATIONS Item Standard Limit Crankshaft: 55.95 X 56.00 mm Crank width “A” Runout limit “C” 0.03 mm 0.35 X 0.65 mm Big end side clearance “D” 1.0 mm 0.010 X 0.025 mm Big end radial clearance 0.8 X 1.0 mm Small end free play “F”...
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SPEC MAINTENANCE SPECIFICATIONS TIGHTENING TORQUES ENGINE Tightening Thread torque Part to be tightened Part name Q’ty Remarks size size mSkg Cylinder head blind plug Screw Cylinder head and cylinder Bolt Cylinder head Bolt (Timing chain side) Cam sprocket cover Screw Valve cover Bolt Plate...
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SPEC MAINTENANCE SPECIFICATIONS Tightening Thread torque Part to be tightened Part name Q’ty Remarks size size mSkg Drive sprocket Bolt Shift cam (Segment) Screw Shift pedal Bolt Pick up coil Screw Neutral switch Screw Stator coil Screw Starter motor Screw...
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SPEC MAINTENANCE SPECIFICATIONS Item Standard Limit Tightening sequence Cylinder head Crankcase...
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SPEC MAINTENANCE SPECIFICATIONS CHASSIS Item Standard Limit Steering system: Steering bearing type Ball bearing No./size of steel balls (upper) 22 pcs. 0.1875 in (lower) 19 pcs. 0.251 in Front suspension: Front fork travel 120 mm Fork spring free length 326.1 mm 321 mm Fitting length 311.1 mm...
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SPEC MAINTENANCE SPECIFICATIONS Item Standard Limit Front brake: Type Single disc Disc outside diameter 267 mm Disc thickness 4 mm 3.5 mm Pad thickness (inner) 6.2 mm 0.8 mm (outer) 6.2 mm 0.8 mm Master cylinder inside diameter 12.7 mm Caliper cylinder 1 inside diameter 30.16 mm Caliper cylinder 2 inside diameter...
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SPEC MAINTENANCE SPECIFICATIONS TIGHTENING TORQUES CHASSIS Tightening torque Part to be tightened Thread size Remarks mSkg Handle crown and front fork Handle crown and steering shaft Handlebar holder (under and upper) Steering ring nut Refer to NOTE Master cylinder and cap (front brake) Handlebar under holder and nut Master cylinder (front brake) Brake hose union bolt (front brake)
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656 X 984 Ω at 20_C/ Pickup coil resistance/color Red – White 624 X 936 Ω at 20_C/ Source coil resistance/color Brown – Green C.D.I. unit model/manufacturer 4WP/YAMAHA Ignition coil: Model/ manufacturer 2JN/YAMAHA Minimum spark gap 6 mm 0.32 X 0.48 Ω at 20_C Primary winding resistance 5.68 X 8.52 kΩ...
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SPEC MAINTENANCE SPECIFICATIONS Item Standard Limit Starter relay: Model/manufacturer MS5D-191/JIDECO Amperage rating 100 A 3.9 X 4.7 Ω at 20_C Coil winding resistance Horn: Model/manufacturer YF-12/NIKKO Maximum amperage 2.5 A Flasher relay: Type Condenser type Model/manufacturer FR2204/MITUBA Flasher frequency 85 cycle/min Circuit breaker: Type Fuse...
SPEC GENERAL TORQUE SPECIFICATIONS GENERAL TORQUE SPECIFICATIONS This chart specifies torque for standard fasten- ers with standard I.S.O. pitch threads. Torque General torque specifications for special components or as- specifications semblies are included in the applicable sections (Nut) (Nut) (Bolt) (Bolt) mSkg of this book.
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SPEC CABLE ROUTING CABLE ROUTING 1 Front brake switch lead Clutch switch coupler A Clamp the handlebar switch 2 Brake hose Handlebar switch lead (left) lead, (left and right), front brake 3 Handlebar switch lead (right) Front flasher lead (left) switch lead, clutch switch lead to 4 Throttle cable Horn lead...
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SPEC CABLE ROUTING 1 Clamp A Align the clamp to the white tape 2 Wireharness on the wireharness 3 High tension cord B Pass the clutch cable through 4 Collar the outside of the throttle cable. 5 Ignition coil C Pass the brake hose and throttle 6 Ground lead cable through the slit of the 7 Ignition coil lead...
SPEC CABLE ROUTING 1 Neutral switch lead Rectifier/ Regulator A Clamp the speedometer cable to 2 Pickup coil lead Thermostatic switch the steering bracket and pass 3 C.D.I. unit Throttle cable the cable to the cable holder. 4 Rear flasher lead (right) Clutch cable B Pass the brake hose through the 5 Rear flasher lead (left)
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SPEC CABLE ROUTING 1 Air filter case 2 Battery 3 Swingarm 4 Battery breather pipe 5 Lid 6 Air filter case drain pipe A Pass the air filter case drain pipe inside the swingarm. 2-23...
Repair if necessary. Rear shock Check operation / oil leakage. absorber Repair if necessary. It is recommended that these items be serviced by a Yamaha dealer. Medium weight wheel bearing grease. (bearing type) ***: Lithium soap base grease. (bush type)
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Check specific gravity. Battery Check breather pipe for proper operation. Correct if necessary. It is recommended that these items be serviced by a Yamaha dealer. **: Medium weight wheel bearing grease. (bearing type) ***: Lithium soap base grease. (bush type) NOTE: Brake fluid replacement: 1.
INSP SIDE COVER, SEAT AND FUEL TANK SIDE COVER, SEAT AND FUEL TANK Order Job name/Part name Q’ty Remarks Side cover, seat and fuel tank Remove the parts in order. removal Side cover (left) Side cover (right) Seat NOTE: Fuel pipe Disconnect the fuel pipe, set the fuel cock lever “OFF”...
INSP VALVE CLEARANCE ADJUSTMENT SR03004 ENGINE VALVE CLEARANCE ADJUSTMENT NOTE: Valve clearance adjustment should be made with the engine cool, at room temperature. When the valve clearance is to be measured or adjusted, the piston must be at Top Dead Cen- ter (T.D.C.) on the compression stroke.
VALVE CLEARANCE ADJUSTMENT/ INSP IDLING SPEED ADJUSTMENT 5. Adjust: : Valve clearance *************************************** Adjustment steps: : Loosen the locknut 1 . : Turn the adjuster 3 in or out with the valve ad- justing tool 2 until specified clearance is ob- tained.
IDLING SPEED ADJUSTMENT/ INSP THROTTLE CABLE ADJUSTMENT 3. Check: : Engine idling speed Out of specification ! Adjust. Engine idling speed: 1,250 1,350 r/min 4. Adjust: : Engine idle speed *************************************** Adjustment steps: : Turn the pilot screw 1 until it is lightly seated. : Turn the pilot screw out by the specified num- ber of turns.
THROTTLE CABLE ADJUSTMENT/ INSP SPARK PLUG INSPECTION : Loosen the locknut 1 on the throttle cable. : Turn the adjuster 2 in or out until specified free play is obtained. Turning in ! Free play is increased. Turning out ! Free play is decreased. : Tighten the locknut.
SPARK PLUG INSPECTION/ INSP IGNITION TIMING CHECK 5. Install: : Spark plug 18 Nm (1.8 m:kg) NOTE: Before installing a spark plug, clean the gasket surface and plug surface. YP303052 IGNITION TIMING CHECK NOTE: Prior to checking the ignition timing, check all electrical connections related to the ignition system.
INSP COMPRESSION PRESSURE MEASUREMENT SR303060 COMPRESSION PRESSURE MEASUREMENT NOTE: Insufficient compression pressure will result in performance loss. 1. Check: : Valve clearance Out of specification ! Adjust. Refer to “VALVE CLEARANCE ADJUST- MENT” section. 2. Start the engine and let it warm up for several minutes.
ENGINE OIL LEVEL INSPECTION/ INSP ENGINE OIL REPLACEMENT CAUTION: : Do not put in any chemicals additives or use oils with a grade of CD a or higher. : Be sure not to use oils labeled “ENERGY CONSERVING II” b or higher. Engine oil also lubricates the clutch and additives could cause clutch slippage.
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INSP ENGINE OIL REPLACEMENT 6. Install: S Drain plug 43 Nm (4.3 mSkg) NOTE: Inspect the O-ring. If it is damaged, replace it with a new one. CAUTION: Before reinstalling the drain plug, do not for- get to fit the O-ring, compression spring and oil strainer.
TIMING CHAINE TENSIONER ADJUSTMENT/ INSP CLUTCH ADJUSTMENT SR******* TIMING CHAINE TENSIONER ADJUSTMENT 1. Remove: S Cap 1 2. Check: S Rod Check the rod end 1 is flush with the adjust- er end 2 . Not flush ! Adjust. 3. Adjust: S Timing chine tension *************************************** Adjustment steps:...
CLUTCH ADJUSTMENT/ INSP AIR FILTER CLEANING 2. Adjust: S Clutch cable free play *************************************** Adjustment steps: Crankcase side S Make sure that the adjuster 1 and locknut 2 are fully tightened. S Loosen the locknut 2 . S Turn the adjuster 1 in or out until the specified free play is obtained.
AIR FILTER CLEANING/ INSP EXHAUST SYSTEM INSPECTION 2. Inspect: S Air filter element 1 Damage ! Replace. 3. Clean: S Air filter element Use solvent to clean the element. NOTE: After cleaning, remove the remaining solvent by squeezing the element. CAUTION: Do not twist the filter element when squeez- ing it.
FRONT BRAKE ADJUST MENT/ INSP REAR BRAKE ADJUSTMENT EB304002 CHASSIS FRONT BRAKE ADJUSTMENT 1. Check: : Brake lever free play a Out of specification ! Adjust. Free play (Brake lever): 5 mm at brake lever end 2. Adjust: : Brake lever free play *************************************** Adjustment steps: : Loosen the locknut 1 .
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INSP REAR BRAKE ADJUSTMENT 2. Adjust: S Brake pedal height *************************************** Adjustment steps: S Loosen the locknut 1 . S Turn the adjuster 2 in or out until the specified pedal height is obtained. Turning in ! Pedal height is decreased. Turning out ! Pedal height is increased.
INSP BRAKE FLUID LEVEL INSPECTION EB304020 BRAKE FLUID LEVEL INSPECTION 1. Stand the motorcycle on a level surface. NOTE: S Make sure the motorcycle is upright when in- specting the brake fluid level. S Stand the motorcycle on its centerstand if it has one.
BRAKE PAD INSPECTION/BRAKE SHOE INSPECTION/ INSP BRAKE LIGHT SWITCH ADJUSTMENT EB304030 BRAKE PAD INSPECTION 1. Operate the brake lever. 2. Inspect: : Brake pad (front) Wear indicators 1 almost touch the brake disc ! Replace the brake pads as a set. Refer to “FRONT BRAKE”...
INSP AIR BLEEDING EB304070 AIR BLEEDING (HYDRAULIC BRAKE SYSTEM) WARNING Bleed the brake system whenever: S The system is disassembled. S A brake hose is loosened or removed. S The brake fluid level is very low. S Brake operation is faulty. Loss of braking performance may occur if the brake system is not properly bled.
AIR BLEEDING/ INSP DRIVE CHAIN SLACK ADJUSTMENT j. Tighten the bleed screw. Bleed screw: 6 Nm (0.6 mSkg) NOTE: If bleeding is difficult, it may be necessary to let the brake fluid settle for a few hours. Repeat the bleeding procedure when the tiny bubbles in the brake system have disappeared.
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INSP DRIVE CHAIN SLACK ADJUSTMENT 1. Check: S Drive chain slack Out of specification ! Adjust. Drive chain slack: 35 mm a Check window b Adjustable limit c Usable limit d Usable range 2. Adjust: S Drive chain slack A Standard B Useful limit *************************************** Adjustment steps:...
INSP STEERING HEAD INSPECTION SR304130 STEERING HEAD INSPECTION WARNING Securely support the motorcycle so that there is no danger of it falling over. 1. Stand the motorcycle on a level surface. NOTE: Stand the motorcycle on its centerstand. 2. Elevate the front wheel by placing a suitable stand under the engine.
FRONT FORK INSPECTION/ INSP REAR SHOCK ABSORBER ADJUSTMENT EB304140 FRONT FORK INSPECTION WARNING Securely support the motorcycle so that there is no danger of it falling over. 1. Stand the motorcycle on a level surface. 2. Check: S Inner tube Scratches/damage ! Replace.
REAR SHOCK ABSORBER ADJUSTMENT/ INSP TIRE INSPECTION Adjustment numbers: Standard Minimum Maximum CAUTION: S Never turn the adjuster beyond the maxi- mum or minimum setting. S Always adjust each shock absorber to the same setting. *************************************** EB304171 TIRE INSPECTION 1. Measure: S Tire inflation pressure Out of specification ! Adjust.
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Ltd. for this model. No guarantee concern- ing handling characteristics can be given if a tire combination other than one ap- proved by Yamaha is used on this motor- cycle. The front and rear tires should al- ways be by the same manufacturer and of the same design.
SPOKE INSPECTION AND TIGHTENING/ INSP WHEEL INSPECTION EB304190 SPOKE INSPECTION AND TIGHTENING 1. Inspect: S Spokes 1 Bending/damage ! Replace. Loose spoke ! Retighten. 2. Tighten: S Spokes NOTE: Be sure to tighten the spokes before and after break-in. Nipple: 2 Nm (0.2 mSkg) EB304180 WHEEL INSPECTION...
INSP BATTERY INSPECTION EB305001 ELECTRICAL BATTERY INSPECTION 1. Remove: S Side covers (left and right) Refer to “SIDE COVER, SEAT AND FUEL TANK” section. 2. Inspect: S Electrolyte level Electrolyte level should be between the up- per 1 and lower 2 level marks. Electrolyte level is too low ! Add electrolyte to proper level.
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INSP BATTERY INSPECTION *************************************** Replace the battery if: S Battery voltage will not rise to a specific value or bubbles fail to rise during charging. S Sulphation of one or more cells occurs, (as in- dicated by the plates turning white, or material accumulating in the bottom of the cell).
INSP BATTERY INSPECTION/FUSE INSPECTION 7. Install: : Battery 8. Connect: : Battery leads CAUTION: Connect the positive lead 1 first and then connect the negative lead 2 . 9. Connect: : Breather hose Be sure the hose is properly attached and routed.
FUSE INSPECTION/ INSP HEADLIGHT BEAM ADJUSTMENT 3. Replace: S Blown fuse *************************************** Replacement steps: S Turn off the main switch. S Install a new fuse with the proper current rat- ing. S Turn on switches to verify operation of related electrical devices.
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CHAPTER 4. ENGINE OVERHAUL ENGINE REMOVAL ..........EXHAUST PIPE, STARTING MOTOR AND WIRE READ .
ENGINE REMOVAL EB400000 ENGINE OVERHAUL ENGINE RE MOVAL EXHAUST PIPE, STARTING MOTOR AND WIRE READ 12 Nm (1.2 m:kg) 20 Nm (2.0 m:kg) Order Job name/Part name Q’ty Remarks Exhaust pipe, starting motor and Remove the parts in order. wire read removal Refer to “SIDE COVER, SEAT AND Side cover, seat and fuel tank FUEL TANK”...
ENGINE REMOVAL ENGINE 33 Nm (3.3 m:kg) 33 Nm (3.3 m:kg) 33 Nm (3.3 m:kg) 33 Nm (3.3 m:kg) 33 Nm (3.3 m:kg) Order Job name/Part name Q’ty Remarks Engine removal Remove the parts in order. Securely support the motorcycle so Engine stay (top) there is no danger of it falling over.
CYLINDER HEAD CYLINDER HEAD CAM SPROCKET COVER 10 Nm (1.0 m:kg) 18 Nm (1.8 m:kg) 2 Nm (0.2 m:kg) 7 Nm (0.7 m:kg) 10 Nm (1.0 m:kg) Order Job name/Part name Q’ty Remarks Cam sprocket cover removal Remove the parts in order. Side cover, seat and fuel tank Refer to “SIDE COVER SEAT AND FUEL TANK REMOVAL”...
CYLINDER HEAD T401030 CYLINDER HEAD REMOVAL 1. Align: : Slit a on the magneto (with stationary pointer b on the crank case cover) NOTE: Turn the crank shaft counterclockwise with a wrench and align the “I” mark c with the cylinder head match mark d when the piston is at TDC on the compression stroke.
CYLINDER HEAD 5. Remove: : Cylinder head NOTE: : Loosen the nuts in their proper loosening sequence. : Start by loosening each nut 1/2 turn until all are loose. YP402000 CYLINDER HEAD INSPECTION 1. Eliminate: : Carbon deposits (from combustion chambers) Use a rounded scraper.
CAM SHAFT AND ROCKER ARMS CAM SHAFT AND ROCKER ARMS 14 Nm (1.4 m:kg) 14 Nm (1.4 m:kg) 8 Nm (0.8 m:kg) Order Job name/Part name Q’ty Remarks Cam shaft and rocker arm removal Remove the parts in order. Cylinder head Refer to the “CYLINDER HEAD”...
CAM SHAFT AND ROCKER ARMS SR****** ROCKER ARM AND ROCKER ARM SHAFT REMOVAL 1. Remove: : Camshaft 1 : Collar (camshaft) 2 NOTE: Use 10 mm bolt 3 to remove the camshaft. 2. Remove: : Rocker arm shaft (intake) : Rocker arm shaft (exhaust) NOTE: Attach a rocker arm shaft puller bolt 1 and weight 2 to the rocker arm shaft and slide out...
CAM SHAFT AND ROCKER ARMS YP402060 ROCKER ARMS AND ROCKER ARM SHAFTS INSPECTION 1. Inspect: : Rocker arm shafts : Rocker arms Wear/Pitting/Scratches/Blue discoloration ! Replace. *************************************** Inspection steps: : Inspect the two contact areas on the rocker arms for signs of unusual wear. : Rocker arm shaft hole.
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CAM SHAFT AND ROCKER ARMS 2. Apply: : Molybdenum disulfide oil (onto the rocker arm and rocker arm shaft) Molybdenum disulfide oil 3. Install: : Rocker arm : Rocker arm shaft 1 NOTE: : Apply engine oil onto the outside of the rocker arm shaft and apply molybdenum disulfide oil onto the inside of the rocker arm.
VALVES AND VALVE SPRINGS VALVES AND VALVE SPRINGS Order Job name/Part name Q’ty Remarks Valves and valve springs removal Remove the parts in order. Cylinder head Refer to “CYLINDER HEAD” section. Rocker arm, Camshaft Refer to “CAMSHAFT AND ROCKER ARMS” section. Valve cotters Refer to “VALVES AND VALVE SPRINGS REMOVAL/INSTALLATION”...
VALVES AND VALVE SPRINGS YP401150 VALVES AND VALVE SPRINGS REMOVAL 1. Remove: : Valve cotters 1 NOTE: Attach a valve spring compressor and attach- ment 2 between the valve spring retainer and cylinder head to remove the valve cotters. CAUTION: Do not compress so much as to avoid dam- age to the valve spring.
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VALVES AND VALVE SPRINGS : Install the new valve guide using a valve guide installer 2 and valve guide remover 1 . : After installing the valve guide, bore the valve guide using a valve guide reamer 3 to obtain proper stem-to-guide clearance.
VALVES AND VALVE SPRINGS : Apply molybdenum disulfide oil to the valve stem. : Install the valve into the cylinder head. : Turn the valve until the valve face and valve seat are evenly polished, then clean off all compound. Valve lapper: 90890-04101 NOTE:...
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VALVES AND VALVE SPRINGS 2. Apply: : Molybdenum disulfide oil (onto the valve stem 3 and oil seal 2 ) Molybdenum disulfide oil 3. Install: : Valve spring seat 1 : Valve stem seat 2 : Valve 3 (into the cylinder head) : Valve spring 4 : Spring retainer 5 NOTE:...
CYLINDER AND PISTON CYLINDER AND PISTON Order Job name/Part name Q’ty Remarks Cylinder and piston removal Remove the parts in order. Cylinder head Refer to “CYLINDER HEAD” section. Timing chain guide (exhaust side) Cylinder/O-ring O-ring Refer to “PISTON RINGS, PISTON AND Dowel pin CYLINDER INSTALLATION”...
CYLINDER AND PISTON YP****** PISTON AND PISTON RINGS REMOVAL 1. Remove: : Piston pin circlip 1 : Piston pin 2 : Piston 3 NOTE: Before removing the piston pin circlip, cover the crankcase opening with a clean towel or rag to prevent the circlip from falling into the crankcase cavity.
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CYLINDER AND PISTON Cylinder bore “C” 57.00 57.02 mm Taper limit “T” 0.05mm Out of round “R” 0.01mm “C” = Maximum D “T” = (Maximum D or D ) – (Maximum D or D “R” = (Maximum D or D –...
CYLINDER AND PISTON EB402110 PISTON RING INSPECTION 1. Measure: : Side clearance Out of specification ! Replace the piston and the piston rings as a set. NOTE: Eliminate the carbon deposits from the piston ring grooves and rings before measuring the side clearance.
CYLINDER AND PISTON EB402120 PISTON PIN INSPECTION 1. Inspect: : Piston pin Blue discoloration/grooves ! Replace, then inspect the lubrication system. 2. Measure: : Piston pin-to-piston clearance *************************************** Measurement steps: : Measure the piston pin outside diameter a . If out of specification, replace the piston pin. Outside diameter (piston pin): 14.978 14.992 mm...
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CYLINDER AND PISTON 2. Install: : Piston 1 : Piston pin 2 : Piston pin clip 3 NOTE: : Apply engine oil onto the piston pins. : The “!” mark a on the piston must face the exhaust side of the cylinder. : Before installing the piston pin clip, cover the crankcase opening with a clean rag to prevent the piston pin clip from falling into the crank-...
CLUTCH 6. Measure: : Free length (clutch spring) a Out of specification ! Replace the clutch springs as a set. Free length (clutch spring): 34.5 mm <Lilmit: 32.9 mm> 7. Inspect: : Dogs on the primary driven gear 1 Scoring/wear/damage ! Deburr or re- place.
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CLUTCH 3. Install: :Lock washer 1 : Nut 2 (clutch boss) 70 Nm (7.0 m:kg) NOTE: Install the clutch boss nut 2 while holding the clutch boss with a clutch holding tool 3 . Clutch holding tool: 90890-04086 4. Bend: : Lock washer tab (along a flat side of the end) 5.
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CLUTCH 9. Check: : Push lever position Push the push lever assembly in the arrow direction and make sure that match marks are be aligned ! Adjust. a Match mark on the push lever assembly b Match mark on the crankcase 10.
SHIFT SHAFT AND SEGMENT SHIFT SHAFT AND SEGMENT 12 Nm (1.2 m:kg) Order Job name/Part name Q’ty Remarks Shift shaft and segment removal Remove the parts in order. Clutch Refer to “CLUTCH” section. Shift pedal Refer to “ENGINE REMOVAL” section. Shift shaft Plate washer Torsion spring...
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SHIFT SHAFT AND SEGMENT 12 Nm (1.2 m:kg) Order Job name/Part name Q’ty Remarks Screw Segment Refer to “SEGMENT INSTALLATION” Dowel pins (short length) section. Dowel pins (long length) Reverse the removal procedure for installation. 4-41...
SHIFT SHAFT AND SEGMENT SR****** SHIFT SHAFT REMOVAL 1. Remove: : Shift shaft assembly 1 NOTE: Push the shift lever arm 2 and the stopper lever 3 to the arrow direction and remove them from the segment. T402200 SHIFT SHAFT INSPECTION 1.
SHIFT SHAFT AND SEGMENT 2. Install: : Segment 1 NOTE: Fit the dowel pin 2 (long length) on the seg- ment to the locating hole a on the sift cam and install the segment. 3. Tighten: : Screw 1 12 Nm (1.2 m:kg) SR****** SIFT SHAFT INSTALLATION 1.
CDI MAGNETO AND STARTER CLUTCH CDI MAGNETO AND STARTER CLUTCH CRANKCASE COVER (LEFT) 7 Nm (0.7 m:kg) Order Job name/Part name Q’ty Remarks Crankcase cover (left) removal Remove the parts in order. Drain the engine oil Refer to “ENGINE OIL REPLACEMENT” section in CHAPTER 3.
CDI MAGNETO AND STARTER CLUTCH CDI MAGNETO AND STARTER CLUTCH 30 Nm (3.0 m:kg) 50 Nm (5.0 m:kg) Order Job name/Part name Q’ty Remarks CDI magneto and starter clutch Remove the parts in order. removal CDI magneto Refer to “CDI MAGNETO REMOVAL/INSTALLATION”...
CDI MAGNETO AND STARTER CLUTCH YP401081 C.D.I. MAGNETO REMOVAL 1. Remove: : Bolt 1 (magneto) : Plain washer 2 NOTE: : Loosen the bolt (magneto) 1 while holding the rotor with a sheave holder 3 . : Do not allow the sheave holder to touch the projection on the magneto.
CRANKCASE AND CRANK SHAFT CRANK CASE AND CRANKSHAFT CRANKCASE 8 Nm (0.8 m:kg) 7 Nm (0.7 m:kg) Order Job name/Part name Q’ty Remarks Crankcase separation Remove the parts in order. Engine Refer to “ENGINE REMOVAL” section. Cylinder head Refer to “CYLINDER HEAD” section. Cylinder and piston Refer to “CYLINDER AND PISTON”...
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CRANKCASE AND CRANK SHAFT 8 Nm (0.8 m:kg) 7 Nm (0.7 m:kg) Order Job name/Part name Q’ty Remarks Timing chain Crankcase Refer to “CRANKCASE SEPARATION/INSTALLATION” section. Dowel pins Reverse the removal procedure for installation. 4-51...
CRANKCASE AND CRANK SHAFT CRANKSHAFT AND BALANCER WEIGHT Order Job name/Part name Q’ty Remarks Crankshaft and balancer weight Remove the parts in order. removal Balancer weight Refer to “BALANCER WEIGHT Crankshaft assembly INSTALLATION” seciton. Dowel pin Refer to “PLUNGER SEAL Plunger seal REMOVAL/INSTALLATION”...
CRANKCASE AND CRANK SHAFT SR401132 CRANKCASE SEPARATION 1. Remove: : Crankcase screws NOTE: : The numbers embossed on the crankcase in- dicate the tightening sequence. Loosen the screws in decreasing numerical order (see numbers on the illustration). : Loosen each screw 1/4 turn at a time and re- move them after all are loose.
CRANKCASE AND CRANK SHAFT T****** CRANKSHAFT INSPECTION 1. Measure: : Crankshaft runout Out of specification ! Replace crankshaft and/or bearing. NOTE: Measure the crankshaft runout with the crank- shaft assembly turning slowly. Runout limit: 0.03 mm 2. Measure: : Big end side clearance Out of specification ! Replace big end bear- ing, crank pin and/or connecting rod.
1. Clean all the gasket mating surface and crankcase mating surface thoroughly. 2. Apply: : Sealant (onto the crankcase mating surfaces) Yamaha bond No.1215: 90890-85505 NOTE: DO NOT ALLOW any sealant to come in con- tact with the oil gallery a .
TRANSMISSION SIFT CAM AND SHIFT FORK TRANSMISSION, SHIFT CAM AND SHIFT FORK Order Job name/Part name Q’ty Remarks Transmission, shift cam and Remove the parts in order. shift fork removal Crankcase separating Refer to “CRANKCASE AND CRANKSHAFT” section. Shift fork guide bar 2 (short length) Shift fork guide bar 1 (long length) Refer to “TRANSMISSION, SHIFT CAM Shift cam...
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TRANSMISSION SIFT CAM AND SHIFT FORK DRIVE AXLE AND MAIN AXLE Order Job name/Part name Q’ty Remarks Drive axle and main axle Disassemble the parts in order. disassembly Second wheel gear First wheel gear Fifth wheel gear Circlip/washer Third wheel gear Forth wheel gear Drive axle Second pinion gear...
TRANSMISSION SIFT CAM AND SHIFT FORK 4. Check: : Shift fork movement (on the guide bar) Unsmooth operation ! Replace the shift fork and the guide bar. NOTE: When damaged the shift fork and mission gear, replace the facing each gear as set. SR****** TRANSMISSION, SHIFT CAM AND SHIFT FORK INSTALLATION...
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CARB CARBURETOR EB600000 CARBURETION CARBURETOR Order Job name/Part name Q’ty Remarks Carburetor removal Remove the parts in order. Side cover Refer to “SIDE COVER, SEAT AND Seat FUEL TANK” section in CHAPTER 3. Fuel tank NOTE: Heater unit lead Disconnect the cable from wireharness. NOTE: Carburetor joint clamp screw Loosen.
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CARB CARBURETOR Order Job name/Part name Q’ty Remarks Carburetor disassembly Disassemble the parts in order. Throttle cable Throttle valve assembly Throttle valve spring Mixing chamber top/O-ring Drain screw assembly Float chamber Gasket (float chamber) Float pin/float Needle valve assembly Refer to “CARBURETOR ASSEMBLY” Main jet section.
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CARB CARBURETOR Order Job name/Part name Q’ty Remarks Pilot screw assembly Refer to “CARBURETOR ASSEMBLY” Pilot jet section. Throttle stop screw assembly Starter plunger assembly Screw/gasket Heater unit/washer Reverse the disassembly procedure for assembly.
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CARB CARBURETOR SR****** CARBURETOR ASSEMBLY CAUTION: : Do not use a wire for cleaning. : Before assembling, wash all parts in clean petroleum based solvent. : Always use a new gasket. 1. Install: : Pilot jet 1 : Pilot screw assembly 2 Pilot screw (turn out): 2 turns out 2.
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CARB CARBURETOR YP600060 FUEL LEVEL ADJUSTMENT 1. Measure: : Fuel level a Out of specification ! Adjust. Fuel level: 3.5 mm below the float chamber line *************************************** Measurement and adjustment steps: : Place the motorcycle on a level surface. : Put a garage jack under the engine to ensure that the carburetors are positioned vertically.
CHAS FRONT WHEEL AND BRAKE DISC EB700000 CHASSIS FRONT WHEEL AND BRAKE DISC 20 Nm (2.0 m:kg) 59 Nm (5.9 m:kg) 23 Nm (2.3 m:kg) Order Job name/Part name Q’ty Remarks Front wheel and brake disc removal Remove the parts in order. WARNING Securely support the motorcycle so there is no danger of it falling over.
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CHAS FRONT WHEEL AND BRAKE DISC Order Job name/Part name Q’ty Remarks Front wheel disassembly Disassemble the parts in order. Oil seal Refer to “FRONT WHEEL ASSEMBLY” section. Bearing Spacer Refer to “FRONT WHEEL Spacer flange DISASSEMBLY/ASSEMBLY” section. Bearing Reverse the disassembly procedure for reassembly.
CHAS FRONT WHEEL AND BRAKE DISC T****** FRONT WHEEL DISASSEMBLY 1. Remove: : Bearings 1 : Spacer Remove the bearings using a general bear- ing puller 2 . CAUTION: Handle the wheel with care not to damage the brake disc. If the brake disc is damaged, replace.
CHAS FRONT WHEEL AND BRAKE DISC 5. Measure: : Front wheel runout Over the specified limits ! Replace. Front wheel runout limits: Radial 1 : 2.0 mm Lateral 2 : 2.0 mm 6. Inspect: : Front wheel bearings Bearings allow free play in the wheel hub or the wheel does not turn smoothly ! Replace.
CHAS FRONT WHEEL AND BRAKE DISC CAUTION: Do not strike the inner race of balls of the bearing. Contact should be made only with the outer race. 2. Install: : Brake disc 1 23 Nm (2.3 m:kg) NOTE: Tighten the bolts (brake disc) in stage using a crisscross pattern.
CHAS FRONT WHEEL AND BRAKE DISC 4. Tighten: : Front wheel axle 59 Nm (5.9 m:kg) : Axle pinch bolt 20 Nm (2.0 m:kg) CAUTION: Before tightening the wheel axle, stroke the front fork several times to check for proper fork operation.
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CHAS FRONT WHEEL AND BRAKE DISC 4. Adjust: : Wheel static balance *************************************** Adjusting steps: : Install a balancing weight 1 on the rim exactly opposite to the heavy spot “X”. NOTE: Start with the smallest weight. : Turn the wheel so that the heavy spot is 90_ : Check that the heavy spot is at rest there.
CHAS FRONT BRAKE FRONT BRAKE BRAKE PAD 23 Nm (2.3 m:kg) Order Job name/Part name Q’ty Remarks Brake pad removal Remove the parts in order. Bolt (caliper support bolt) Refer to “BRAKE PAD REPLACEMENT” Brake pads section. Pad support Reverse the removal procedure for installation.
CHAS FRONT BRAKE SR702010 BRAKE PAD REPLACEMENT NOTE: It is not necessary to disassemble the brake cal- iper and brake hose to replace the brake pads. 1. Remove: : Bolt (caliper support bolt) 1 Move the direction brake caliper 2 to the ar- row mark.
CHAS FRONT BRAKE MASTER CYLINDER 2 Nm (0.2 m:kg) 9 Nm (0.9 m:kg) 30 Nm (3.0 m:kg) Order Job name/Part name Q’ty Remarks Master cylinder removal Remove the parts in order. Drain the brake fluid Rear view mirror (right) Brake lever/compression spring Brake switch Union bolt Plate washer...
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CHAS FRONT BRAKE Order Job name/Part name Q’ty Remarks Master cylinder disassembly Disassemble the parts in order. Rubber boots Circlip Refer to “MASTER CYLINDER Master cylinder kit ASSEMBLY” section. Spring Reverse the disassembly procedure for reassembly. 6-11...
CHAS FRONT BRAKE 2. Install: : Circlip 1 Install the circlip securely into the master cyl- inder groove. : Rubber boot 2 YP****** MASTER CYLINDER INSTALLATION 1. Install: : Master cylinder 1 : Master cylinder bracket 2 9 Nm (0.9 m:kg) CAUTION: Install the master cylinder bracket 2 with the “UP”...
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CHAS FRONT BRAKE WARNING : Use only designated quality brake fluid: Otherwise, the rubber seals may deterio- rate, causing leakage and poor brake per- formance. : Refill with the same type of brake fluid:mix- ing fluids may result in a harmful chemical reaction and lead to poor performance.
CHAS FRONT BRAKE CALIPER 30 Nm (3.0 m:kg) 40 Nm (4.0 m:kg) 23 Nm (2.3 m:kg) Order Job name/Part name Q’ty Remarks Caliper removal Remove the parts in order. Drain teh brake fluid Brake hose holder Union bolt Plain washer Refer to “CALIPER INSTALLATION”...
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CHAS FRONT BRAKE 6 Nm (0.6 m:kg) Order Job name/Part name Q’ty Remarks Caliper disassembly Disassemble the parts i order. Brake pad Refer to “BRAKE PAD” section. Caliper piston Dust seal Refer to “BRAKE CALIPER DISASSEMBLY/ASSEMBLY” section. Piston seal Bleed screw/Cap Reverse the disassembly procedure for reassembly.
CHAS FRONT BRAKE SR****** BRAKE CALIPER DISASSEMBLY NOTE: Before disassembling either brake caliper, drain the brake fluid from the brake hose, mas- ter cylinder, brake caliper and reservoir tank. 1. Remove: : Brake caliper pistons : Caliper piston seals/dust seals *************************************** Removal steps: : Use a piece of wood 1 to secure the smaller...
CHAS FRONT BRAKE 1. Install: : Piston seals 1 : Dust seal 2 WARNING Always use new caliper piston seals. 2. Install: : Caliper piston 1 Apply brake fluid to the outer surface and install. YP****** CALIPER INSTALLATION 1. Install: : Caliper 1 40 Nm (4.0 m:kg) : Caliper support bolt 2...
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CHAS FRONT BRAKE WARNING : Use only the designated quality brake fluid: other brake fluids may deteriorate the rubber seals, causing leakage and poor brake performance. : Refill with the same type of brake fluid: mixing brake fluids may result in a harmful chemical reaction and lead to poor brake performance.
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CHAS REAR WHEEL, REAR BRAKE AND DRIVE CHAIN Order Job name/Part name Q’ty Remarks Rear wheel disassembly Disassemble the parts in order. Bearing Collar Refer to “REAR WHEEL Spacer DISASSEMBLY/ASSEMBLY” section. Oil seal Bearing Reverse the disassembly procedure for reassembly. 6-22...
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CHAS REAR WHEEL, REAR BRAKE AND DRIVE CHAIN 9 Nm (0.9 m:kg) Order Job name/Part name Q’ty Remarks Brake shoe plate disassembly Disassemble the parts in order. Brake shoe kit Tension springs Refer to “BRAKE SHOE PLATE Cam lever ASSEMBLY” section. Indicator plate Camshaft Reverse the disassembly procedure for...
CHAS REAR WHEEL, REAR BRAKE AND DRIVE CHAIN 4. Clean: : Drive chain Put it in kerosene, and brush off as much dirt as possible. Then remove the drive chain from the kerosene and dry it. Drive chain lubricant: Engine oil SR****** BRAKE SHOE PLATE ASSEMBLY 1.
CHAS REAR WHEEL, REAR BRAKE AND DRIVE CHAIN SR****** REAR WHEEL ASSEMBLY 1. Install: : Bearing 1 : Spacer 2 : Collar 3 : Bearing 4 NOTE: : Apply the lithium soap base grease on the bearing and oil seal lip when installing. : Use a socket that matches the outside diame- ter of the race of the bearing.
CHAS FRONT FORK FRONT FORK 48 Nm (4.8 m:kg) 30 Nm (3.0 m:kg) 40 Nm (4.0 m:kg) Order Job name/Part name Q’ty Remarks Front fork removal Remove the parts in order. Front wheel Refer to “FRONT WHEEL AND BRAKE DISC” section. Brake hose holder Caliper Front fender...
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CHAS FRONT FORK 65 Nm (86.5 m:kg) Order Job name/Part name Q’ty Remarks Front fork disassembly Disassemble the parts in order. Cap bolt/O-ring Collar/washer NOTE: Fork spring Drain the fork oil. Dust cover Retaining clip Refer to “FRONT FORK Washer (oil seal) DISASSEMBLY/ASSEMBLY”...
CHAS FRONT FORK 2. Measure: : Fork spring a Front fork spring free length: 326.1 mm <Wear limit> 321 mm Over the specified limit ! Replace. 3. Inspect: : Rod assembly 1 Bends/damage ! Replace. CAUTION: : The front fork has a built-in piston rod and a very sophisticated internal construction which are particularly sensitive to foreign material.
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CHAS FRONT FORK 2. Install: : Piston metal 1 : Oil seal 2 Use the fork seal driver weight 3 and the at- tachment 4 . NOTE: Before installing the oil seal 2 , apply lithium soap base grease onto the oil seal lips. CAUTION: Make sure that the oil seal numbered side faces upward.
CHAS FRONT FORK 7. Measure: : Oil level a Out of specification ! Adjust. Oil level: 165 mm (from the top of the inner tube fully compressed and without the fork spring) NOTE: Hold the fork in an upright position. 8.
CHAS HANDLEBAR HANDLEBAR 9 Nm (0.9 m:kg) 20 Nm (2.0 m:kg) Order Job name/Part name Q’ty Remarks Handlebar removal Remove the parts in order. Headlight assembly NOTE: Handlebar switch lead (left and right), Disconnect the connector. front brake switch lead and clutch switch lead Master cylinder bracket Master cylinder...
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CHAS HANDLEBAR 9 Nm (0.9 m:kg) 20 Nm (2.0 m:kg) Order Job name/Part name Q’ty Remarks Handlebar switch (left) Grip (left) Refer to “HANDLEBAR REMOVAL” section. Lever holder (left) Upper holder Refer to “HANDLEBAR INSTALLATION” Handlebar section. Reverse the removal procedure for installation.
CHAS HANDLEBAR YP****** HANDLEBAR REMOVAL 1. Remove: : Grip (Left) *************************************** Removal steps: : Remove the grip end (left). : Blow with compressed air between the hadle- bar and adhesive side of the grip to remove. *************************************** YP704020 HANDLEBAR INSPECTION 1.
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CHAS HANDLEBAR 3. Install: : Master cylinder 1 : Master cylinder bracket 2 9 Nm (0.9 m:kg) NOTE: Install the master cylinder bracket with the “UP” mark facing upward. 4. Adjust: : Throttle cable free play : Brake operation. Refer to “THROTTLE CABLE ADJUST- MENT/BRAKE LEVER ADJUSTMENT”...
CHAS STEERING STEERING UNDER BRACKET 40 Nm (4.0 m:kg) 1st step: 38 Nm (3.8 m:kg) 2nd step: 7 Nm (0.7 m:kg) Order Job name/Part name Q’ty Remarks Under bracket removal Remove the parts in order. Front fork Refer to “FRONT FORK” section. Handlebar Refer to “HANDLEBAR”...
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CHAS STEERING 40 Nm (4.0 m:kg) 1st step: 38 Nm (3.8 m:kg)2nd step: 7 Nm (0.7 m:kg) Order Job name/Part name Q’ty Remarks Ball race (upper) Ball Refer to “STEERING REMOVAL/ Ball INSTALLATION” section. Ball race (center) Ball race (lower) Reverse the removal procedure for installation.
CHAS STEERING YP704010 STEERING REMOVAL WARNING : Securely support the motorcycle so that there is no danger of it falling over. : Stand the motorcycle on a level surface. 1. Remove: : Ring nut 1 Use a exhaust and steering nut wrench 2 . Exhaust and steering out wrench: 90890-01268 WARNING...
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CHAS STEERING EB704030 STEERING INSTALLATION Reverse the “REMOVAL” procedure. Note the following points. 1. Lubricate: : Bearings (upper and lower) : Ball races Recommended lubricant Lithium-soap base grease 2. Install: : Ring nut 1 7 Nm (0.7 m:kg) Refer to “STEERING HEAD INSPECTION” section in CHAPTER 3.
CHAS REAR SHOCK ABSORBER AND SWINGARM REAR SHOCK ABSORBER AND SWINGARM 40 Nm (4.0 m:kg) 45 Nm (4.5 m:kg) 20 Nm (2.0 m:kg) 30 Nm (3.0 m:kg) Order Job name/Part name Q’ty Remarks Rear shock absorber and swingarm Remove the parts in order. removal Rear wheel Refer to “REAR WHEEL, REAR BRAKE...
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CHAS REAR SHOCK ABSORBER AND SWINGARM T***** SWINGARM INSPECTION 1. Inspect: : Swingarm side play Free play exists ! Check side clearance. : Swingarm up and down movement Unsmooth movement/bending/rough spots ! Grease or replace bearings, solid bushes and collars. 6-44...
ELEC SWITCH INSPECTION YP-N SWITCH INSPECTION INSPECTION STEPS Using pocket tester, check switches for continu- ity between their terminals to determine wheth- er they are correctly connected. Replace the switch component if any of the combinations does not produce the correct reading.
ELEC IGNITION SYSTEM SR802010 TROUBLESHOOTING IF THE IGNITION SYSTEM FAILS TO OPERATE. (NO SPARK OR INTERMITTENT SPARK) Procedure Check: 1. Spark plug 6. Source coil resistance 2. Ignition spark gap 7. Main switch 3. Spark plug cap resistance 8. Engine stop switch 4.
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ELEC IGNITION SYSTEM YP***** 2. Ignition spark gap S Disconnect the spark plug cap from the spark plug. S Connect the ignition checker as shown. Spark plug cap S Turn the main switch to “ON”. S Check the ignition spark gap S Check the spark by pushing the starter switch, and increase the spark gap until a misfire occurs.
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ELEC IGNITION SYSTEM YP***** Tester (+) lead ! 4. Ignition coil resistance Orange Terminal S Disconnect the ignition coil connector from Tester (–) lead ! the wireharness. Ground Terminal S Connect the pocket tester (Ω 1) to the ignition coil. S Check if the primary coil has the specified re- sistance.
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ELEC IGNITION SYSTEM YP****** 5. Pickup coil resistance S Disconnect the pickup coil coupler from the wireharness. S Connect the pocket tester (Ω 100) to the pickup coil coupler. Tester (+) lead ! White Terminal Tester (–) lead ! Red Terminal S Check the pickup coil has the specified re- sistance.
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ELEC IGNITION SYSTEM YP***** NO CONTINUITY 8. Engine stop switch Refer to “SWITCH INSPECTION” section. Replace the handlebar switch (right). CONTINUITY YP***** NO CONTINUITY 9. Sidestand switch Refer to “SWITCH INSPECTION” section. Replace the sidestand switch CONTINUITY YP***** 10.Wiring connection POOR CONNECTIONS S Check the connection of the entire ignition system.
ELEC ELECTRICAL STARTING SYSTEM SR****** STARTING CIRCUIT OPERATION The starting circuit on this model consists of the starter motor, starter relay, and the neutral relay. If the engine stop switch and the main switch are both closed, the starter motor can operate only if: The transmission is in neutral (the neutral relay is closed).
ELEC ELECTRICAL STARTING SYSTEM YP803020 TROUBLESHOOTING IF THE STARTER MOTOR FAILS TO OPERATE. Procedure Check: 1. Fuse 7. Engine stop switch 2. Battery 8. Neutral switch 3. Starter motor 9. Sidestand switch 4. Starter relay 10. Clutch switch 5. Neutral relay 11.
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ELEC ELECTRICAL STARTING SYSTEM YP****** 3. Starter motor WARNING S Connect the battery positive terminal and starter motor cable using a jumper S A wire used as a jumper lead must have the lead equivalent capacity as that of the battery S Check the starter motor operation.
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ELEC ELECTRICAL STARTING SYSTEM YP****** 5. Neutral relay S Remove the relay from the frame. S Connect the pocket tester (Ω 100) to the Battery and the relay connecter. Tester (+) lead ! Terminal 1 Tester (–) lead ! Terminal 3 Battery (+) lead ! Terminal 2 Battery (–) lead !
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ELEC ELECTRICAL STARTING SYSTEM YP****** NO CONTINUITY 10.Clutch switch Refer to “SWITCH INSPECTION” section. Replace the clutch switch. CONTINUITY YP****** NO CONTINUITY 11. Start switch Refer to “SWITCH INSPECTION” section. Replace the handlebar switch (right). CONTINUITY YP****** 12.Wiring connection POOR CONNECTION S Check the connections of the entire starting system.
ELEC ELECTRICAL STARTING SYSTEM STARTER MOTOR 7 Nm (0.7 m:kg) Order Job name/Part name Q’ty Remarks Starter motor removal Remove the parts in order. Drain the engine oil Refer to “ENGINE OIL REPLACEMENT” section in CHAPTER 3. Crankcase cover (right) Refer to “CLUTCH REMOVAL”...
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ELEC ELECTRICAL STARTING SYSTEM YP803034 Inspection and repair 1. Inspect: : Commutator Dirt ! Clean it with #600 grit sandpaper. 2. Measure: : Commutator diameter a Commutator wear limit: 27 mm Out of specification ! Replace the starter motor 3. Measure: : Mica undercut a Mica undercut: 0.7 mm...
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ELEC ELECTRICAL STARTING SYSTEM 6. Measure: : Brush spring force Fatigue/out of specification ! Replace as a set. Brush spring force: 540 X 660 g 7. Inspect: : Oil seal Wear/damage ! Replace. YP****** Assembly Reverse the “Disassembly” procedure. Note the following points. 1.
ELEC CHARGING SYSTEM YP804010 TROUBLESHOOTING IF THE BATTERY IS NOT CHARGED Procedure Check: 1. Fuse 4. Stator coil resistance 2. Battery 5. Wiring system (entire charging system) 3. Charging voltage NOTE: Remove the following parts before trouble- Use the special tools specified in the trouble- shooting.
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ELEC CHARGING SYSTEM YP****** 3. Charging voltage S Connect the engine tachometer to the spark plug lead. S Connect the pocket tester (DC20V) to the battery. Tester (+) lead ! Battery (+) terminal Tester (–) lead ! Battery (–) terminal Right side S Measure the battery terminal voltage.
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ELEC CHARGING SYSTEM YP****** 5. Wiring connection POOR CONNECTION Check the entire charging system for connec- tions. Refer to “CIRCUIT DIAGRAM” section. Correct. CORRECT Replace the rectifier/regulator. 7-22...
ELEC LIGHTING SYSTEM YP805010 TROUBLESHOOTING IF THE HEADLIGHT, AUXILIARY LIGHT, HIGH BEAM INDICATOR LIGHT, TAILLIGHT AND/OR METER LIGHT FAIL TO COME ON. Procedure Check: 1. Fuse 4. Lights switch 2. Battery 5. Dimmer switch 3. Main switch 6. Wiring connection (entire lighting system) NOTE: Remove the following parts before trouble- Use the special tools specified in the trouble-...
ELEC LIGHTING SYSTEM NO CONTINUITY YP****** 4. Lights switch Refer to “SWITCH INSPECTION” section. Replace the handlebar switch (left). CONTINUITY YP****** NO CONTINUITY 5. Dimmer switch Refer to “SWITCH INSPECTION” section. CONTINUITY Replace the handlebar switch (left). YP****** 6. Wiring connection POOR CONNECTIONS S Check the connections of the entire lighting system.
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ELEC LIGHTING SYSTEM S Turn the main switch to on position. S Turn the lights switch to on position. S Turn the dimmer switch to low beam or high OUT OF SPECIFICATION beam. S Check for voltage (12 V) on the lead at bulb socket connectors.
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ELEC LIGHTING SYSTEM YP805022 3. The taillight fails to come on. NO CONTINUITY 1. Bulb and bulb socket Refer to “SWITCH INSPECTION” section. Replace the bulb and/or bulb socket. CONTINUITY 2. Voltage : Connect the pocket tester (DC20V) to the bulb socket connector.
ELEC SIGNAL SYSTEM YP806010 TROUBLESHOOTING IF THE FLASHER LIGHT, BRAKE LIGHT AND/OR INDICATOR LIGHT FAIL TO COME ON. IF THE HORN FAILS TO SOUND. Procedure Check: 1. Fuse 3. Main switch 2. Battery 4. Wiring connection (entire signal system) NOTE: S Remove the following parts before trouble- S Use the special tools in the troubleshooting shooting.
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ELEC SIGNAL SYSTEM YP****** 4. Wireharness S Check the connections of the entire signal POOR CONNECTION system. Refer to “CIRCUIT SYSTEM WIRING DIA- GRAM” section. Correct. CORRECT Check condition of each of the signal sys- tem’s circuits. Refer to “SIGNAL SYSTEM CHECK” section. 7-30...
ELEC SIGNAL SYSTEM YP806020 SIGNAL SYSTEM CHECK 1. If the horn fails to sound. NO CONTINUITY 1. Horn switch Refer to “SWITCH INSPECTION” section. Replace the left handlebar switch (left). CONTINUITY 2. Voltage : Connect the pocket tester (DC20V) to the horn lead.
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ELEC SIGNAL SYSTEM YP806022 2. If the brake light fails to come on: NO CONTINUITY 1. Bulb and bulb socket Refer to “SWITCH INSPECTION” section. Replace the bulb and/or bulb socket. CONTINUITY NO CONTINUITY 2. Brake switch (Front/Rear) Refer to “SWITCH INSPECTION” section. Replace brake switch.
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ELEC SIGNAL SYSTEM YP806023 3. If the flasher light and/or turn indicator light fails to blink. NO CONTINUITY 1. Bulb and bulb socket Refer to “SWITCH INSPECTION” section. Replace the bulb and/or bulb socket. CONTINUITY NO CONTINUITY 2. Turn switch Refer to “SWITCH INSPECTION”...
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ELEC SIGNAL SYSTEM 5. Voltage S Connect the pocket tester (DC20V) to the bulb socket connector. At flasher light (left) Tester (+) lead ! Chocolate lead Tester (–) lead ! Black terminal At flasher light (right) Tester (+) lead ! Dark green lead Tester (–) lead ! Black terminal OUT OF SPECIFICATION S Turn the main switch to on.
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ELEC SIGNAL SYSTEM 3. Voltage S Connect the pocket tester (DC20V) to the fuel gauge coupler. Tester (+) lead ! Brown terminal Tester (–) lead ! Sky blue terminal S Turn the main switch to on position. OUT OF SPECIFICATION S Select the gear position in neutral.
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ELEC SIGNAL SYSTEM 2. Heater unit resistance S Remove the heater unit from the carburetor. S Connect the pocket tester (Ω 1) to the heater unit. Tester (+) lead ! Terminal Tester (–) lead ! Terminal S Check the heater unit for specificated resis- tance.
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CHAPTER 8. TROUBLE SHOOTING STARTING FAILURE/HARD STARING ......POOR IDLE SPEED PERFORMANCE ......POOR MEDIUM AND HIGH SPEED PERFORMANCE .
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TRBL STARTING FAILURE/HARD STARTING SHTG EB90000 TROUBLESHOOTING NOTE: The following troubleshooting does not cover all the possible causes of trouble. It should be helpful, however, as a guide to troubleshooting. Refer to the relative procedure in this manual for inspection, adjustment and replacement of parts.
TRBL POOR MEDIUM AND HIGH SPEED PERFORMANCE SHTG EB902000 POOR MEDIUM AND HIGH SPEED PERFORMANCE POOR MEDIUM AND HIGH SPEED PERFORMANCE Refer to “STARTING FAILURE/HARD STARTING” section. (Fuel system, electrical system, compres- sion system and valve train) Carburetor Air filter : Improperly adjusted fuel level : Clogged air filter element : Clogged main nozzle...
TRBL OVER HEATING/FAULTY BRAKE SHTG SR905000 SR906001 OVER HEATING OR OVER-COOL- FAULTY BRAKE POOR BRAKING EFFECT Front brake OVER HEATING : Worn brake pad Ignition system : Worn brake disc : Improper spark plug gap : Air in brake fluid : Improper spark plug heat range : Leaking brake fluid : Faulty C.D.I.
TRBL FAULTY SIGNAL AND LIGHTING SYSTEM SHTG YP909000 FAULTY SIGNAL AND LIGHTING SYSTEM HEADLIGHT DARK FLASHER BLINKS SLOWER : Improper bulb : Faulty flasher relay : Too many electric accessories : Insufficient battery capacity : Hard charging (nearly discharged) : Faulty rectifier/regulator : Improper bulb : Faulty battery : Faulty main and/or turn switch...