Yamaha QT 50F User manual

1

NOTICE
ThismanualhasbeenwrittenbyYamahaMotorCompanyforuseby
AuthorizedYamahaDealersandtheirqualifiedmechanics.Inlightofthis
purposeithasbeenassumedthatcertainbasicmechanicalpreceptsand
proceduresinherenttoourproductarealreadyknownandunderstoodby
thereader.Thisservicemanualhasbeenwrittentoacquaintthemechanic
withcommondisassembly,inspection,reassembly,maintenance,and
troubleshootingproceduresassociatedwiththismachine.
TheResearch,Engineering,andServiceDepartmentofYamahaare con-
tinuallystrivingtofurtherimproveallmodelsmanufacturedbythecom-
pany.Modificationsarethereforeinevitableandsignificantchangesin
specificationsorprocedureswillbeforwardedtoallAuthorizedYamaha
Dealersand will, whereapplicable,appearinfutureeditionsofthismanual.
Particularlyimportantinformationis distinguished inthismanualbythe
followingnotations:
NOTE: A NOTEprovideskeyinformationtomakeprocedures
easierorclearer.
CAUTION: A CAUTIONindicatesspecialproceduresthatmustbe
followedtoavoiddamagetothemotorcycle.
WARNING:A WARNINGindicatesspecialproceduresthatmustbe
followedtoavoidinjurytoa motorcycleoperatororper-
soninspectingorrepairingthemotorcycle.
QT50F
SERVICEMANUAL
1stEdition-March1979
2ndPrinting,November 1980 OCL
3rdPrinting,July 1981 OCL
ALLRIGHTSRESERVEDBY
YAMAHAMOTORCORPORATION, U.S.A.
PRINTEDIN U.S.A.
LIT-11616-01-31
I
J

SECTIONINDEX
V
GENERALINFORMATION
PERIODICINSPECTIONAND
ADJUSTMENTS
ENGINEOVERHAUL
j
//
CARBURETlON
CHASSIS
ELECTRICAL
'vVys
APPENDICES
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MS
CHAPTER 1.GENERALINFORMATION
1-1. MACHINEIDENTIFICATION1-2
1-2.SPECIALTOOLS1-2

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CHAPTER1.GENERALINFORMATION
1-1. MACHINEIDENTIFICATION
The fr&me serialnumberislocatedonthe
frontslideoftheheadpipeassembly.The
firstthreedigitsidentifythemodel.Thisis
followedbya dash.Theremainingdigits
identify:theproductionnumberoftheunit.
POCKET TESTER'
ToolNo.90890-03096
FLYWHEELHOLDINGTOOL
Tool No.90890-01235
Theengineserialnumberislocatedona
raisedbossonthelowerleftsideofthe
engine.Engineidentificationfollowsthe
samecodeasframeidentification.
1. Engineserialnumber
ft
•J%
u$
I®.
' -a
4W
m
~
.sB
wmmB^LM
ELECTROTESTER
Tool No.90890-03021
DIALGAUGE
ToolNo. 90890-03110
FLYWHEELPULLER
ToolNo. 90890-01189
1-2

CRANKICASE SEPARATIONTOOL
Tool,No. 90890-01135
CRANK
Tool Nci
INSTALLERPOT
90890-01274
ADAPTER CRANKINSTALLERBOLT
Tool No!, 90890-01278(M12)
EXHAU >T RINGandSTEERINGNUTWRENCH
Tool No. 90890-01268
Additional ToolsandSupplies
1. Thicknessgauge set
2. Torque wrench
3.Tirepressuregauge
4. Fluidmeasuringcup
5.Micrometer
6.Verniercaliper
7.Cylindergauge
8.Magneticstand
9.
10.
11.
12.
13.
14.
15.
BOLT
ToolNo.90890-01305
CRANKINSTALLERBOLT
ToolNo.90890-01275
HEXAGONWRENCH
Toll No. 90890-01306 (25)
90890-01307(22)
Greasegun
Yamalube 4-cycle oil
Yamalube 2-cycle oil
Wheelbearinggrease
YamahabondNo.4
YamahaChainandCableLube
Lithiumbasewheelbearinggrease
(Ex. SHELL LETHINAXA)
1-3

CHAPTER2.
PERIODICINSPECTIONAND ADJUSTMENTS
2-1.
2-2.
2-3.
2-4.
2-5.
INTRODUCTION2-2
MAINTENANCEINTERVALSCHARTS2-2
A.MaintenanceIntervals2-2
B.LubricationIntervals2-3
ENGINE2-3
A.Carburetor2-3
B.AirCleaner2-4
C.AutolubePump2-4
D.EngineandTransmissionOil2-5
E.CylinderHead2-6
CHASSIS2-6
A. Brake andWheel(FrontRear)2-6
B.SteeringandSuspension2-7
ELECTRICAL2-8
A.IgnitionTiming2-8
B.SparkPlug2-8
C.Battery2-9
D.HeadlightBeamAdjustment 2-10

CHAPTER2.
PERIODICINSPECTIONANDADJUSTMENTS
2-1. INTRODUCTION
Thischapterincludesallinformationnecessarytoperformrecommended
inspectionandadjustment.Thesepreventivemaintenanceprocedures,if
followed, willinsuremorereliablevehicleoperationanda longerservice
life. Theneedforcostlyoverhaulworkwillbegreatlyreduced.Thisinfor-
mationappliesnotonlytovehiclesalreadyinservice,butalsotonew
vehiclesthatarebeingpreparedforsale.Anyservicetechnicianperform-
ingpreparationworkshouldbefamiliarwiththisentirechapter.
2-2. MAINTENANCEINTERVALSCHARTS
Thefollowingchartsshouldbeconsideredstrictlyasa guidetogeneral
maintenanceandlubricationintervals.Youmusttakeintoconsideration
thatweather,terrain,geographicallocation,anda varietyofindividual
uses. Thistimescheduleshouldbealteredtomatchindividualowners'
requirements.Forexample,ifthemotorcycleiscontinuallyoperatedinan
areaofhighhumidity,thenallpartsmustbelubricatedmuchmore fre-
quentlythatshownonthecharttoavoiddamagecausedbywatertometal
parts.
A.Mainter
cioj
Cylinderhead
Sparkplug
Airfilter
Carburetor
Autolubepurr
*Brakesystem
*Wheelsandt
*Suspensions
Fuelpetcock
•Battery
*Lights/Signal
ance Intervals
tern
/Exhaustsystem
P
(complete)
res
stem
I* Fittings/Fastehers
Remarks
Decarbonize
Inspect/Cleaningorreplaceasrequired
Wet type-Must bewashedanddampedwith
Yamalube 2-cycle OilorSAE20motoroil
Checkoperation/Fittings
Clean/Refit/Adjust
Check/Adjust/Airbleeding
Check/Adjustas required-Repair asrequired
Checkpressure/Wear/Balance/Runout
Check operation/Repair asrequired
Clean/Flushtankasrequired
Top-up/Checkspecificgravityandbreather
pipe
Checkoperation/Replaceasrequired
Tightenbeforeeachtrip and/or...
•
Initial
1
month
O
O
O
O
O
O
O
O
O
3
months
0
O
O
O
O
O
O
O
O
O
O
O
6
months
O
O
O
O
O
O
O
0
O
O
o
o
o
Unit:
km (mi)
Thereafterevery
6
months
O
0
O
O
O
3
months
O
O
o
o
o
o
1
year
O
*Indicatespre-operation checkitems.
2-2

B.LubricationIntervals
Unit:km(mi)
1 '
Item
•Transmissionoil
*Conrolandmete
cables
Throttlegrip an<j
housing
Brakelever,
Brakecamshaft
Steeringbearing
Speedometer ge
housing
Wheelbearings
Middleandfinal
gear
*Indicatespre-opera
r
s
ar
tionchec
Remarks
Replace/Warmengine
beforedraining
Applythoroughly
Applylightly
Applylightly
Applylightly
Inspectthoroughly/Pack
moderately
Inspectthoroughly/Pack
moderately
Donotover-pack
yearlyor...
Seepage5-7torepack
grease
kitems.
Type
Yamalube 4-cycle OilorSAE
10W/30 type"SE"motoroil
SAE10W/30 motoroil
Lithiumbasegrease
Lithiumbasegrease
Lithiumbasegrease
Medium-weightwheelbearing
grease
Lithiumbasegrease
Medium-weightwheelbearing
grease
Lithiumbasewheelbearinggrease
(EX. SHELLLETHINAXA)
Initial
1
month
O
3
months
Check
O
O
o
6
months
O
O
O
0
0
Check
Thereafterevery
6
months
O
O
0
1
year
O
O
2
years
2
years
O
2
years
2-3. ENGIN
A. Carburetcir
1. Pilotairscrew
Turnairadjustingscrewuntilitlightly
seats, thenbackitouttospecification.
This adjustment canbemadewith
enginestopped.
Airscrew(Turnsout):1-3/4[1-1/2]
[]:AfterengineserialNo. 3L5-702401
2. Startthe bngine andletitwarmup.
3.Throttle stop screw
Turnthrottlestopscrewinoroutto
1. Pilotairscrew 2. Throttlestopscrew
achieve
specified
Idlingspeed
mooth engineoperation
die speed. at
1,700 r/min
4. Throttlecable
a.Throttlecable2.
Loosencableadjusterlocknut(attop
ofcarburetor)andturncableadjuster
untilspecifiedfreeplayisobtained.
Retightenlocknut.
NOTE:
Thepilotair knd throttlestopscrewsare
separateadjustmentsbuttheymustbe
adjustedatthesametimetoachieve opti-
mum operating conditionatengineidle
speeds.
Freeplay: 1.0 mm(0.04in)
1. Adjuster2. Lock nut
2-3
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b.Throttle
cable2
directioh
cable1
After engine idlespeedandthrottle
aresetcheckplayintuning
ofthrottlegrip.Theplay
should tie 2 ~ 3 mm(0.08 ~ 0.12in)
atgripflange.Loosenthelocknutand
turnthewireadjustertomakethe
necessaryadjustment.Afteradjusting,
besure io tightenthelocknutproperly.
1. Adjuster
B.AirClean
1. Remove
element
sr
theaircleanercasecapand
assembly.
2.
3.
4.
Wash the elementgently,butthorough-
ly,in solvent.
Squeezeexcesssolventoutofelement
anddry.
Poura small quantityof20W.motoroil
onto cleelner elementandworkthor-
oughlyintotheporousfoammaterial.
Element ihust bedampwithoilbutnot
dripping.
5.Re-installtheelementassembly,case
coverandseat.
NOTE:
Eachtimecleanerelementmaintenanceis
performed, checktheairinlettothecleaner
caseofobstructions.Checktheaircleaner
jointrubbertothecarburetorandmanifold
fittingsforanair-tight seal. Tightenallfit-
tingsthroughlytoavoidthepossibilityofun-
filteredairenteringtheengine.
r-CAUTION:
Neveroperatetheenginewiththeair
cleanerelementremoved.
Thiswillallow unfiltered airtoenter,
causingrapidwearandpossibleengine
damage.Additionally,operationwith-
outthecleanerelementwillaffectcar-
buretorjettingwithsubsequentpoor
performanceandpossibleengineover-
heating.
C.AutolubePump
1. Airbleeding
Tobleedtheoilpump,firstremovethe
bleedscrew.Startengineandrunat
idlingspeed.Thenpulltheoilpump
wireasmuchaspossible,andcontinue
toruntheengineuntilallairbubbles
disappearfromtheoilflowingoutfrom
thebleederhole.
Reinstallbleedscrew.
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2. Oil pumpi wireadjustment
a.Removetheslackinthrottlewire2 by
turningtheadjustingscrewattachedto
thecarburetor.
b.Loosenthelocknut.
c.Turn thei adjustingscrewsothatthe
markontheadjustingpulleyisaligned
withthePhillipsheadscrewattachedto
the adjusting plate.
d. Screw in thelocknutuntiltight.
1. Adjustingpulley
2. Phillipshead
Minimu
Remove
casea
anddial
stroke
nj> pumpstrokeadjustment
thesidecoverandaircleaner
ss^mbly, setthemagneticstand
gauge, andmeasurethepump
whilekeepingtheengineidle.
a.Toadjusttheplungerstroke,firstloosen
thelocknut.
b.Turntheadjustingboltinoroutfor
properadjustment.
Turningtheadjustingboltclockwise
decreasestheplungerstroke;while
turningcounterclockwiseincreasesthe
plunger stroke.
c.Whenthecorrectstrokeisattained,
tightenthelocknut.
Minimumstroke
Maximumstroke
Pulleycolorcode
Pulleyadjustmark
0.20 ~ 0.25mm
(0.008 ~ 0.010in)
0.95 ~ 1.10mm
(0.037~ 0.043in)
Yellow
7777777f//7777777
D.EngineandTransmissionOil
1. Engineoil(Autolubeoil)
Recommendedoil:
Yamalube 2-cycle Oil
a.Oilwarninglight
Bulbcheck:Turnthemainswitchto
"•*•"position, and iftheoilwarninglight
comeson,itisingoodcondition.
Ifnot,checkthelightbulbandlead
wires.
Oillevelcheck:Turnthemainswitchto
"ON" position,andiftheoilwarning
lightdoesnotcomeon,theoillevelin
thetankiscorrect.Iflightsup,add
Yamaha 2-oycle engineoil.Forfurther
details,refertopage6-9.
2-5

1 Oillevelgauge
2. Oilwarninglight
3 Oilwarninglightcheckswitch (Main switch)
4 Battery
2. Transmission
a.Replacethetransmissionoiloncea
year.
1. Oilfillercap
Recommendedoil:
Yamalube 4-cycle oilor
SAE10W/30"SE" motoroil
b.A drainplugislocatedonthebottomof
therightcrankcasecover.Withtheen-
ginewarm,removethepluganddrain
oil. Re-installplugandaddfreshoil.
Transmissiondrainplugtorque:
2m-kg(14ft-lb)
Transmissionoilquantity:
Total(dry):350cc(0.37US.qt)
Exchange:300cc(0.32US.qt)
E.CylinderHead
Checktorqueofcylinderheadholdingnuts.
Tightenina crisscrosspattern.
Cylinderheadnuttorque:
1.0m-kg(7.0ft-lb)
2-4. CHASSIS
A.BrakeandWheel(Front,Rear)
1. Inspectionandadjustmentofbrakes
Checkthefreeplayofbothbrakelever.
Ifthefreeplayisoffthespecification,
makeanadjustmentbyturningadjuster
andlocknut.
Front
10~ 20mm
1 2; (0.4- 0.8in)
1. Adjuster2.Locknut
Rear
10 ~ 20mm (0.4 - 0.8in)
1Adjuster2.Locknut
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1. Drainplug
2-6

Adjustment and brakeshoereplace-
mentCamshaftleveradjustment
Ifthefreeplayadjustment of thebrake
leverisimpossiblewiththeadjusterand
atthesametime, if theindicator is still
before the limitmark,make an adjust-
mentbyturning the camshaftleverone
tooth.
-CAUTION:
Do not turn the camshaftlevermore
thanonetooth.
Front
Limitmark
Indicatorplate
Rear
Indicatorplate \
V. V Limit
»^—J"*-mark
7
Front
(D
Rear
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1. Adjuster
2. Camshaftlever 3.Camshaft
4. Indicatorplate
3.Brakeshoereplacement
When the indicatormark is lined up
with the limitmark,replace the brake
shoe.
Whenreplacing the brakeshoe,bring
thepunchmark onthe camshaftlever
toalignwith the punchmark onthe
camshaft.
Wheninstallingtherearbrake, be sure
toaligntheprojectiononthedriveshaft
housingwiththecenter of thecamshaft
lever.
1. Indicatorsetposition 2. Punchmark 3. Setposition
4. Frontaxle
Checkaxlenut.
Frontaxlenuttorque:
5.5 m-kg (40 ft-lb)
5. Rear axle
Checkaxlenut.
Rearaxlenut tome: 6 m-kg(43ft-lb)
6.Tirepressure
Front
Rear
1.25kg/cm2(18 psi)
2.0kg/cm2(28psi)
B.SteeringandSuspension
1. Steeringhead adjustment
Thesteeringassemblyshouldbecheck-
edperiodically for any looseness. Do
thisasfollows:
a.Blockmachine up sothatfrontwheel is
offtheground.
b.Graspbottom of forks and gentlyrock
forkassemblybackward and forward,
checking for anyloosenessinthesteer-
ingassemblybearings.
2-7

Ifsteeringheadneedsadjustment
usingsteeringnutwrench,adjuststeer-
ingheadfittingnutuntilsteeringheadis
tightwithoutbindingwhenforksare
turned.
NOTE:
Excessivetighteningofthisnutwillcause
rapidwearofballbearingsandraces.
Re-checkforloosenessandfreedomof
movement.
d. Tightensteeringfittingbolt.
NOTE:
Aftercompletingsteeringadjustmentmake
certainforkspivotfromstoptostopwithout
binding. Ifbindingisnoticed,repeatadjust-
ment.
2. Suspension
a.Checkallsuspensionforproperopera-
tion.
b. Checkallsuspensionforpropertight-
ness.
2-5.ELECTRICAL
A.IgnitionTiming(C.D.I.)
1. Ignitiontimingischeckedwithtiming
lightbyobservingthepositionofthe
stationarypointermarkedonthecrank-
caseandthemarksonthemagneto
flywheel. Ignitiontimingofthis
motorcycleisnon adjustable,
forchecking.
1. Mark
2. Stationarypointer
2. Checkingtheignitiontiming
Usinga timinglightchecktoseethat
thestationarypointerandmarkonthe
magnetoflywheel,arealigned.
a. Removethe crankcase cover (L).
b.Connectthetiminglighttothespark
plugleadwire.
c.Starttheengineandkeepitrunningat
thespecifiedspeed.Usea tachometer
forchecking.
Timingcheckingspeed:5,000 r/min
d. Whilerunningtheengineatthespe-
cifiedspeed,checktoseethatthesta-
tionarypointerisalignedwiththemag-
netomark.Ifthemarksareoutofalign-
mentchecktoseethatthewoodruff
keyisbrokenorcrankshaftassemblyis
out ofalignment.
Ignitiontiming:
0.94mm(0.037in) B.T.D.C.
B.SparkPlug
Thesparkplugindicateshowtheengineis
operating. Iftheengineisoperating correct-
ly,andthemotorcycleisbeingriddencor-
rectly,thenthetipofthewhiteinsulator
aroundthepositiveelectrodeofthespark
plugwillbea mediumtancolor.Ifthein-
sulatorisverydarkbrownorblackcolor,
thena plugwitha hotterheatrangemightbe
required. Thissituationisquitecommon
duringtheenginebreak-inperiod.
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2-8

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Iftheinsulatortipshowsa verylighttanor
whitecolorisactuallypurewhiteandglazed
orifelectrodesshowsignsofmelting,thena
sparkplugwitha colderheatrangesisre-
quired. Remember,theinsulatorareasur-
roundingthepositiveelectrodeofthespark
plugmustbea mediumtancolor.Ifitisnot,
checkcarburetion,timingandignitionadjust-
ments.Thesparkplugmustberemovedand
checked.' Checkelectrodewear,insulator
color,andelectrodegap.
Sparkpluggap:
0.6 ~ 0.7mm(0.024 0.028in)
Engineheatandcombustionchamber
depositswillcauseanysparkplugtoslowly
breakdownanderode.Iftheelectrodes
finallybecometooworn,orifforanyreason
youbelievethesparkplugisnotfunctioning
correctly,replaceit.
Wheninstallingthe plug, alwayscleanthe
gasketsurface,usea newgasket,wipeoff
anygrimethatmightbepresentonthesur-
faceofthespark plug, torquethesparkplug
properly.
StandardSparkPlug
NGK:BP4HS
lightingTorque
2.0m-kg(14ft-lb)
C.Battery
Apoorlymaintainedbatterywilldeteriorate
quickly.Thebatteryfluidshouldbechecked
atleastonce a month.
1. Thelevelshouldbebetweentheupper
andlowerlevelmarks.Useonlydistilled
waterforrefilling.Normaltapwater
containsmineralswhichareharmfulto
abattery;therefore,refillonlywith
distilledwater.
2. Alwaysmakesuretheconnectionsare
correctwheninstallingthebattery.The
redleadisforthe 4- terminalandthe
blackleadisforthe— terminal.Make
surethebreatherpipeisproperly con-
nectedandisnotdamagedorobstruct-
ed.
1. Upperlevel2.Lowerlevel
1. Batterybreatherpipe
NOTE:
Anewbatterymustbeproperlyservicedand
chargedbeforeinstallation.
Chargingcurrent:
Charginghours: 0.4Amps. 10hrs.
r-WARNING:
Batteryelectrolyteispoisonousand
dangerous,causingsevereburns,etc.
Containssulfuricacid.Avoidcontact
with skin, eyesorclothing.
Antidote:
EXTERNAL-Flush withwater.
INTERNAL-Drink largequantitiesof
waterormilk.Followwithmilkofmag-
nesia,beateneggorvegetableoil.Caff
physicianimmediately.
Eyes:
Flushwithwaterfor 15 minutesandget
promptmedicalattention.
2-9

Batteriesproduceexplosivegases.
Keepsparks,fame,cigarettes,etc.
away.Ventilatewhenchargingorusing
inenclosedspace.
Alwaysshieldeyeswhenworkingnear
batteries.
KEEPOUTOF REACHOFCHILDREN.
D.HeadlightBeamAdjustment
Whennecessary,adjusttheheadlightbeam
asfollows:
1. Abouthorizontallybytighteningor
looseningtheadjustingscrew,asinthe
illustration.
Toadjusttotheright:tightenthescrew
Toadjusttotheleft:loosenthescrew
2. Adjustverticallybymovingthe head-
lightbody.
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1. Adjustingscrew
2-10

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CHAPTER3.ENGINEOVERHAUL
3-1. REMOVAL3-2
A.PreparationforRemoval3-2
B.Exhaust3-2
C.Carburetor3-2
D.Removal3-3
3-2.DISASSEMBLY3-3
A.ReedValveAssembly3-3
B.MainStand3-3
C.KickCrank(KickStarter)3-3
D.DriveShaft(RearArm Comp.) 3-3
E.Magneto3-3
F.CylinderHeadandCylinder3-4
G.PistonPinandPiston3-4
H.CrankcaseCover,Right3-4
I. ClutchAssemblyandPrimaryDriveGear3-5
J. KickShaftAssembly,DriveGearandKickPinionGear3-5
K.Transmission3-5
LCrankcase3-6
M.Crankshaft . 3-6
3-3.INSPECTIONANDREPAIR3-7
A.CylinderHead3-7
B.Cylinder3-7
C.PistonPinandBearing3-7
D.Piston3-7
E.PistonRings3-8
F.AutolubePump3-8
G.Clutch3-9
H.KickStarter3-9
I. Transmission3-9
J. Crankshaft3-10
K.BearingandOilSeals3-10
L.Crankcase3-10
3-4.ENGINEASSEMBLINGANDADJUSTMENT3-10
A.CrankshaftInstallation3-10
B.Crankcase 3-11
C.TransmissionInstallation 3-11
D.KickStarterAssembly 3-11
E.PrimaryDriveGearandClutchAssembly 3-12
F.CrankcaseCover(Right)3-12
G.Piston3-12
H.Cylinder3-12
I. CylinderHead3-12
3-5.INSTALLING3-13

CHAPTER3.ENGINEOVERHAUL
3-1. REMOVAL
A.PreparationforRemoval
1. Alwayscleanenginebeforeremoval.
Donotbeginworkuntilallpropertools
areavailable.Aspartsareremoved,
cleanthemandplacethemintraysin
order1 ofdisassembly.
2. Starttheengineandwarmitfora few
minutes.Turnoffanddraintransmission
oil. Beforebeginingoftheservicing,
fullycooltheenginedown.
B.Exhaust
1. Removefootrestprotectors.(R.L)
2. Removesidecovers.(R.L)
3.Removesparkplugcap.
4. Removethefootrestfromtheframe.
5.Removeexhaustpipeassembly.
C.Carburetor
1. Removetheignitioncoilandcoil
bracket.
2. Disconnectthemagnetoleadwire.
3.Removetherearfender.
4. Removetherearbrakecablefromshaft
drivehousing.
5.Removethenutandrearwheelfrom
shaftdrivehousing.
NOTE:
Immediatelywhentherearwheelisremoved
fromthehousing,placea woodenframeor
blockundertherearcarriertokeepthema-
chineupright.
6.Removeaircleanerjointandclip,air
cleanercaseassembly.
1. Aircleanercase
2. Aircleanerjoint 3.Clip
7.Removethedeliverypipefromcarbure-
tor.
8.Removethepumpcover(1)andpump
cableandoilpipe.
NOTE:
Donotleavetheoilpipedisconnectedfrom
theoilpump,oroilwillflowoutoftheoil
tank.Itisadvisabletoplugtheopenpipeend
witha propersizescrew.
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B.MainStand
Removemainstandandbracketfromengine.
9.Removethecarburetor.
D.Removal
1. Removerearshockabsorberholding
boltfromshaftdrive.
2. Removetheenginemountingboltand
removeenginefromfrontsideofframe.
3-2.DISASSEMBLY
A.ReedValveAssembly
Removemanifold,reedvalveassembly hold-
ingscrewsandreedvalveassembly.
1. Reedvalveassembly
2. Reedvalve
3.Reedvalvestopper
4. Panhead screw
5.Springwasher
6.Reedvalveplate
7.Valveseatpacking1
8.Valveseatpacking2
9. Manifold
10. Panheadscrew
C.KickCrank(KickStarter)
Removekickcranksecuringboltandkick
crank.
D.DriveShaft(RearArm Comp.)
Removereararmcomp.fromengine.
E.Magneto
1. Removeleft crankcase coverscrewand
cover.
2. Removetheflywheelsecuringnut.(use
Flywheelholdingtool)
1. Flywheelholdingtool
3-3

nil
3.Installflywheelpulleronflywheeland
tightenit.
NOTE:
Thepullerbodyhaslefthandthread.
4. Whileholdingpullerbody,tightenpush
bolt.Thiswillpullflywheeloffthe
taperedendofthecrankshaft.
1. Flywheelpuller
1. C.D.I, magnetassembly
2. Rotorassembly
3.Magnetbase
4. Sourcecoil
5. Pulser assembly
6.Lightingcoil
7.Leadwireassembly
8.Clamp
9. Pan headscrew
10. Springwasher
11. Paaheadscrew
12. Springwasher
13. Panheadscrew
14. Springwasher
15. Panheadscrew
16. Earth 1 terminal
17. Earth2 terminal
18. Flatheadscrew
NOTE:
Loosensparkplugbeforelooseningcylinder
head.
1. Cylinderhead
2. Cylinderheadgasket
3.Sparkplug
4. Cylinderbody
5.Cylindergasket
6. Stud bolt
7.Platewasher
8.Hexagonnut
PistonPinandPiston
Removepistonpinclipfrompiston.
NOTE:
Beforeremovingthepistonpinclip,cover
thecrankcasewitha cleanragsoyouwill
notaccidentallydroptheclipintothecrank-
case.
2. Pushpistonpinfromoppositeside,then
pullout.Protectpinwithrag.
NOTE:
Beforeremovingpistonpin,deburrclip
grooveandpinholearea.
II
I
H•,-
I
••'
I
T >•"•'
F.CylinderHeadandCylinder
Removecylinderheadholdingnuts,cylinder
headgasketandcylinderhead.Loosencylin-
derheadholdingnuts1/4turneach,then
removenut.
H.CrankcaseCover,Right
Removerightcrankcasecoverscrewsand
cover.
3-4