HOW TO U S E CONTE NTS TH I S MAN UAL Follow the recommendations in this manual to MAINTENANCE ensure that the vehicle is in peak operating condition and the emission levels are within..the TRANSMISSION standards set by the U.S. Environmental Protec tion Agency.
Grease by coatin g or filling where specified. center or larger dia. bolts in a X pattern where the sequence is not specified ..Use Trac or Trac-recommended parts After reassembling, check every part for proper and lubricants. installation, movement or operation. '·...
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SPEED The engine power is transfered to clutch weight comp. (1) installed at the right end of crank shaft. When the engine is accelerated to 3 RPm, clutch weights are outstretched then stick fast to inside ,000 of clutch drum(2} by the cent1ifugal force. Then the power is transfered to the idle shaft through pinion gear and primary gear(3} ENGINE SECTION...
A I R C L EA N E R DISASSEMBLY left · side Remove the cover and un screw the 6mm bolt. Loosen :the air cleaner band then remove the air cleaner. • • Unscrew the 5mm screw then disassemble the air cleaner body. ( 1} 6mm boh deane1·...
F U E L SYSTEM Fuel cock con nected pieces o f lines tank. from the fuel position. HON" position o f fuel cock, and another is for "RES" One line is DISASSEMBLY R.emove the remaining fud tank. Disco n nect the fuel li' ri:e ' from fuel cock ii' ·...
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CLEANING • Wash the tank inside with the clean gasoline. • Clean the fuel passage of fuel cock by compressed air. • Wash the filter with gasoline then apply the compressed air. Wash the inside of filter cap with gasoline. •...
· · ,_ . · · SPA R K P LUG remove the the plug cap then • Disconnect spark plug with plug wrench. Visually Discard inspect the spark plug. it if the insulator is cracked or chipped. � Mesure the spark plug gap with a wire type feeler gauge.
IGN I T I O N T I M I NG INSPECTION • t!ie ignition t iming with . the timing Check light. ::.- · ',,:· . �\ i�'.tbrr'�ttif tfik\ina�i;rilark • Timing aligns .. · w ith th e T D C: ·...
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CAR B U R E TO R REMOVAL • Remove the left side cover, then dis connect the air cleaner. • Close the fuel cock then disconnect the fuel line. • Unscrew the 5rnm bolt o n carburetor top plate then remove the throttle valve and start valve at once.
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0 ISASSEMBL Y • • Remove the pilot jet. Remove the float chamber from • mixing body. Unscrew the piloi screw and remove • Separate the float by removing the float the spring. • pin. Be sure not to miss. the pin.
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LEAN I NG IONIC INSPECT valve ins p ection wear - · -- - -·-- Check Carburet o r body of contacting area. of float inspect the movement valve. needle C leaning the jets • jets Blow open all and body opening com p ressed with 3.
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ASSEMBLY • Assemble acco rding to reverse order disassembly. THROTTLE STOPSCREW PILO T _AIR SCRE W NEED LE JET � Assemble VAL VE SEA start valve and throttle valve at once. Take care not t o damage the packing materials. ADJUSTMENT •...
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BATTERY Battery is 6V-4AH and used only for horn, stop light and tum signal lights. When stop light is used so frequently, . . check the battery. needed, charge the ba. t tery. (l) Fuse box INSPECTION s, cha When following conditions ccur the battery with new one.
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.., :- �.I \ • · . ; .·· • Check stop light to b e turned on when � · � holding b r ake Make sure that stopper nut it well fixed. • . · I',•; .•'( ·...
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$ R I V E C H A I N f� SPECTION motor- • Turn the engine off, place the slac� cy cle on the main stand. Check the lower drive chain .run midway be-,. tween the sprockets. Drive chain slack ·...
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T I R E Check tire pressu : , when the tires are · cold. Front Driver only 1.75 kg/cm2 Rear 2.0kg/cm2 SPO K E Check looseness of spokes. loosened, tighten and check with torque wrench. Torque 3.5-4.5kg.cm (25.3-32.5 in-lb) 2} Torque I) Nipple wrench wrench...
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COMPR ESS ION PR ESSUR E T E ST � • Remove the 'spark plug and set the com:.. Normal pressure 8kg m 3 • In case of higher p1essure, it means excessive carbon deposit on combu�tion cham&er. • In case of lower pressere, check the cylinder, piston and piston rings.
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1�Ass§rv1a1: remove · · t he Unsct�w the c a.p htif/fh e n • ·· cap..muffler " • uH out · �, · ..· '. · : . : · : :· : <: ·...
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TRANSM I SS I O N O I L C HANG E DRAIN • Remove the right side cover remove the oil filler cap and drain bolt. Drain the oil. engine Before draining the oil, warm_ to normal operating temperature. drain bolt REFILL •...
ENGI NE REMOVAL/I NSTALLAT I ON SER V I CE I NFO R MATION GENERAL INFORMATION maintenance and follow ing inspectic>n can be accomplished with the engine installed. group • Cylinder head, cylindc:r and piston Reed • valve and oil pump. drive gear.
ENG I N E R E MOVAL ,, . · · � : . ,.:; J V�ts � · starting Remove the right and lefr Let t h e e n ine be cool before • Close the fuel coc-k then remove •the a:i.r cleaner removal, if the engine get hot.
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• Remove the high-tension cord. Disconnect the wires from generator. • A.C. • Remove the front under cover . . ·•. • Disconnect the oil line from oil tank to oil pump .
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• Remove the step bars. Remove the engine comp. · · ' · ·...
C Y L INDER HEAD CY L INDE R • Remove spark plug high tension cord clip then remove the spark ping. :·.: � ..Remove the cylinder head. Remove the cylinder head gasket. • Remove the muffler. •...
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':": INSPECTION Check I.D. of cylinder. Remove the carbon deposits. inside Visually check the of cylinder. Most Remove the carbon womed portion are usually 'A'. deposits on combus· area where ports are located. tion chamber and ex haust port. Measure the diameter at the p osition and 'C' in two d irection 'A', 'B' of 'a' and 'b '.
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CYLINDER ASSEMBLY When replacing cylinder or pisron, refer to cylinder piston making chart of service information. Replace when disassembled. NOTE: saine maked ones. sure to When re p lacin g cylinder or piston select make Install piston ring as shown. Check the Marking on same as cylinder...
PISTON P ISTON R I NG AND P I STON P I N DISASSEMBLY Place shop towel To xemove the piston pin, press the over '*ank case opening, then remove pin by finger tip. If necessary, ham· mer with punch slightly. piston pin clips.
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PISTON INSPECTION Visuall y check the defects of pistou. Marking on piston PistonO.D. 39, 970-39, 965 975-39, 970 39,980-39,975 39.985-39.980 Measure the O.D. of piston at a point .5mm froin the bottom. 39. 96!1 3!-l. 98fi 'Standard O.D. Limit 39. 900m1 11 Service Measure the I.D.
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PISTON RING INSPECTION Measure the ring-end-gap by inserting rings Note: Measure the ring-end-gap at with piston into cylinder. the smallest inner-diameter · of the cylinder. Piston ring-end-gap. 0.15�0.35mm Top ring 0.15-0.35mm Second ring Measure the clearance between piston ring and piston. Clearance 0.
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SMALL-END-BEARING INSPECTION Ex � ess lo <;> seness of small end bearing will cause cngme noise. check th Diassemble bearing and condition of retainer and roller. If the parts are broken or defaced, replace them with new ones. Check the looseness of bearing inserting piston.pin into the con-rod...
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PISTON RING AND PIN ASSEMBLY • Note: Place a shop towe� over the.crank case opening. repl_ ac ing. • Make sure that t he proper rings are installed when Install Cr-plated Install ordinary ring Install piston ring with mark· ing facing Install piston with the anow mark...
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.. . REEO VAL\I E • eJs{5mm) of the crank case the reed valve;. Disass ebly;:,:-,I,3. �)?:� ��;� and-remove :� : : . � · � · : : "' ®@ • Remove the reed the reed valve body, from Reed plate Allowance of reed sto er 4.8mm...
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C LUTCH/D R I V E SHAFT /O I L PUMP/ A. C.G E N E RATOR , ... •, .. ·. : ·., SERVICE INFORM.ATIO� CLUTCH COMPLETE DRIVE SHAFT COMPLETE A.c. OIL PUMP DRIVE G GENERATOR .�: SERV I C E I N FOR MAT ION. Maintenance and inspection can be accomplished with engine installed.
.C LUTCH COMPLETE ..· • . DISASSEMBLY ::·· · • Remove the.clutch side cover. : ' ·· Use plastic hammer when needed. • Hold magneto with magneto-rotor holder and loosen lock nut by 19mm-socket wrench. Lock nut •...
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• Pull out a clip com p . from the clutch speed clutch weight remove the high ass'y. Note: D on't disassembie s p ring. the clutch drum Clutch comp. 4) Lock nut 2) One-way needle bearing 5) Lock ivasher 3) Low speed clutch weight comp.
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Measure O.D. of low clutch weight with a vernier caliper. ( standard ) Service limit 85.35 weight Clytch -lmm Replace weight complete when the clutch weight is worn out too much. Don't disassemble the weight spring. It is not possible to assemble it without a special tool.
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ASSEMBLY CLUTCH • Install the clutch drum comp. clutch • Install the low-speed comp. Install locking and tighten the lock washer nut while holding magneto with magneto rotor holder. Torque 5.50-6.60 kg-cm • Apply grease on thrust washer then install the clutch side cover.
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DR I V E SHAFT COMP INSPECTlON t he drive 1111 Remove the gear from shaft. • Check the condition of the drive . shaft spline. gear. • Check defacing . · condition · bdtr Check the condition of drive shaft •...
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PUMP O I L D R I V E G EAR DISASSEMBLY • Remove the oil pump. • Remove the oil pump pm1on gear. (Be careful not to lose a thrust washer located. at the end of the pinion gear.) •...
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C R AN K/ K I C K STA R T/ I D L E SHAFT ---·---·--· ----------..·······- -· .. - · - · - · - · · · · - - - ·...
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C RANK CASE D ISASSEM B LY DISASSEMBLY · • Loosen n screws and separate crank- ca�e plastic hammer. by using Note: Be careful not to damage the crankcase using a screw driver. The case can be easily separated with a hammer. Pan screw Remove the crank shaft from the crank •...
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1 -- ---- C R A N K S H AFT · 1 I NSPECT I O N • Set the crank shaft on a stand or blocks read runout at point gauge. and B usin� a dial Se1vicc limits O.lOmm (0.004mJ O.lOmm (0.004in) •...
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• Measure connecting rod big and side clearance wit h a feel er gauge. Service l i mit 0.8inm (0;032in) • Measure the bending clearance o f the connecting rod. limit 0.05-0.4mm Service j r- -- C R A N K S HAFT B EAR I N G LOOS E N E SS •...
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C R A N K SHAFT COMP 5) :-<ec�dl.<: weight R-cran k bearing weight Thrust L··crank washer w<>.sl1ci Connec ting- rod 7 ) Crank. shafl. pit1 •t Crank Wood · ruff OIL SEAL INSPECTION Vi�11ally inspect tht uil $Cab. H tli1.:n:: i� wo: n defect, 1'epJ;.u:c it wiLh 111�w out or...
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PEDAL SHA FT I NSPECTION REDAL SHA FT I NS P E CT I ON • Check the condition of deformation of pedal shaft and sprocket. • Check the condition of Needle Bearing. 1 ) Shaft, Starter Pedal 2) Housing Comp., Start Needle Bearing Apply grease to the needle bearing and 3) Washer, Trust (20MM) washers when assembling.
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IDL E SHAFT COMP. · · . .. Remove the balL receiver froni th� idle • :,''· · • : : ::1.\ shaft. · id!� froni • Remove the gear • shaft. Check the condition, 6f the shaft. �plfue. • Check condftion ·...
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C R A N K CASE ASS E M B L Y crank • Apply the oil to the shaft bearings. �issi�� The oil should tie sarl?e · Note: Be careful .not to damage oil seal or take away the s p ring by applyng enou g h grease to crank shaft and idle shaft .
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STEER I NG I F R ONT WHEEL I BRAKE SUSPENSION 8 - 0 SERVICE INFORM ATION STEERING STEM/ STEEBING STEM DISA S SEMBLY · ING STEM ASSEMBLY :, . SERV ICE I N F ORMAT I O N SPECIF ICATlON: Standard Service...
STE E R I NG STE M • R emove t h � handle bar. • Remov e t h e head light and s��h<l om:e · • Remove t he front w h eel. • Remove t h e front forks. •...
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STEER I N G STEM ASSE MBLY Press the ball • race into the steering pipe with ball race remover. • · Apply steel balls, ball races grease to races. • Install steering stem steering head pipe. thread to the •...
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BATTE R Y/CH AN G I NG SERVICE INF ORMATION S - Q BATTERY REMOVA L / SPECIFIC GRAVITY CHECKING 9 - 1 BATTERY C HA RGING/CHA RGING SYSTEM PERFOR 9 - 2 MANCE TEST 9 "- 3 A . C. GENERATOR/ REGUL AT0R, RECTIFIER S E R V I C E I N FO R MAT I O N GENER.AL INFORMATION the electrolyte and if needed refili vvith distiJJcd wattr.
BATTER Y REMOVAL • Remove the right side cover. • Disconnect the ground cable. •; � Disconnect the negative termini.I · o f th • battery. · · · , band 1) Battery SPEC I F IC G R AV ITY ·...
BATTERY CHARG I NG Remd�e<i'p:� • cell caps from the battery. :-:. •· Connect the changer po�itive (+) cable · the.�t: �attcry posltiv � (+)'" tertninaL · . · • '"'."' Connect :·/the charger negativ�/ the battery negative \�harging current : 0.4 ·...
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Remove the righ t side Disconnect ��� F • coupler of A.C. . , . erator. ·· �� Measure the resistances betwe white terminal, and green and between yellow · rminal and green 0.3-0.6n . White/Green 0.2•0.6n Yellow/Green • · ·...
· ·· T C H ES and discbnrlett • the head light Remdve the 4-P coupler (white color) -..• Continuity should exist betw({,en color wires indicated by interconnected circles chart. on each IGNITION SW iCH Color code STAR T U R N SIGNAL SW ITCH Grey Light Blue...
H O R .N SW ITCH R/Lg Color code Free Push I G N ITION COI L I NSPECT ION • Measure the resistances o f the primary and secondary coils. Resistances Q.2-0.3U Primary coil 3.4-4.2!1 Secondary coil STOP SW ITCH •...
T R O U B L E SHOTT I N G ENGINE DOES NOT START OR IS HA A D TO ENGINE L A CKS POWER 1 1 - 2 POOR PERFORMANCE AT LOW A ND IDLE SPEEDS/ � 1 1 - 3 POOR PERFORMANCE AT HIGH SPEED 1 1 - 4 ·...
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ENGi. N E. LAC KS; POW.ER � : · : . : . . : ... : : · · · · ;:'' . ! :; · Probable Cause , : , · Lightly sp_e.ed · . · .· 'J:: n gi � accelerate engine �' Cl(jgged:air cleaner...
POO R P E R FOR MANCE AT LOW AND I D L E SPEEDS Probable Cause Faulty CDI unit 1. Check ignition timing Faulty pulse generator Correct Incorrect---- -- -- -- -- -i l) Fuel mixture too rich 2. Check Carburetor air screw (Perform idle drop) for proper ad justment Fuel air mi x ture too lean...
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. · ..· · . · '' ' · · , � · � : � : ;.• .:�: \.J; • tire Loss of control-------·-_:;_:. . ��.:..-'-::.--------Check pressure Probable Cause If steering is heavy (2) Damaged steering cones or steel balls 2.