Yingang YG125-30B User manual

YG125-30B MaintenanceManual Foreword
1
Foreword
Withtheeverincreasingvarietiesofmotorcycles,newstructuresandnewtechniqueshaveincreasinglybeenapplied.
TohelpYINGANGTECHNOLOGYCo.,Ltdusersandmaintenancepersonnelbetterunderstandthemaintenance,
adjustmentandrepairtechniquesofYG125-30Amotorcycle,wepreparedthismaintenancemanual.Thismanualis
expectedtofacilitatetheYINGANGTECHNOLOGYCo.,Ltdusersandmaintenancepersonnelandprovidetechnical
guidanceforthem.
ThemasterstrokeofthemanualistheYG125-30Amotorcycle,andthecontentsinChapter1-Chapter3areapplicable
totheadjustmentofvariouspartsofthemotorcycle.Chapter4-18describesvariousconstitutingpartsofthemotorcycle
respectively.Chapter19containstheelectricalsystemdiagram.
Thestandardmaintenanceprocedures,maintenanceprecautionsandgeneralmaintenanceknowledgearenot
coveredinthismanual.Anyuserormaintenancepersonnelwhoneedstheaboveinformationmayrefertotherelated
materials
Allmaterials,chartsandvariousdata,aswellasperformanceindicesreferencedherein,areforthelatestmodelinour
productfamilyatthedatethismanualisprinted.YINGANGTECHNOLOGYCo.,Ltd. shallhavetheright to,atanytime,
amendthismanualwithoutpriornotice.ThecopyrightofallpartsofthismanualbelongstoChinaYINGANG
TECHNOLOGYCo.,Ltd. andnounitsorindividualsareallowedtoreprintitthewithoutconsentofourcompany.
Wehopeyouwillenjoythecomfortandpleasureitbringstoyouduringyourdriving!

YG125-30B MaintenanceManual Contents
2
Contents
1. Overview 1-12
2. Lubricationsystem 13-23
3. Inspectionandadjustment 24-39
4. Fuelsystem 40-45
5. Removalandinstallationofengine 46-50
6. Cylinderhead,cylinderandpiston 51-67
7. ClutchandRightcrankcasecover 68-78
8. Magnetoandstartingsystem 79-87
9. Crankcase,crankshaftandShiftmechanism 88-104
10. Frameandexhaustsystem 105-109
11. Frontwheel,frontoverhangandsteeringstem 110-121
12. Rearwheelandrearoverhang 122-127
13. Generalremarksofelectricalsystem 128
14. Powersupplysystem 129-131
15. Startingsystem 132-134
16. Illuminationsignalsystem 135-140
17. Electricalstartingcontrolsystem 141-144
18. Enginemanagementsystem 145-156
19. ElectricalSystemDiagram 157
EngineVehicle body
Electrical system Overview

YG125-30B Maintenance Manual Overview
1
1Overview
EngineNumberPosition BarTool
AboutMotorcycleMaintenance MaintenancePeriodTable
TechnicalDataofMainPerformance SymbolDescriptions
StandardTorqueValues
EngineNumberPosition
PhotoofCompleteVehicle:
FrameNumberPosition: EngineNumberPosition:
EngineNumber
FrameNumber

YG125-30B Maintenance Manual Overview
2
MaintenancePrecautions
1. Wheneverreassemblingafterbeingdisassembled,
replacenewwashers,sealingmembers,etc.
2. Whilefasteningboltsornuts,proceedindiagonal
crossingsequencetograduallyscrewdowntothe
requiredtorquefor2to3tries.
3. Afterbeingdisassembled,thepartsand
componentsshouldbecleanedbeforebeing
inspectedandmeasured
Tocleanthespareparts,useonlythecleaning
fluidthatisincombustibleorhashighignitionpoint.
Beforereassembling,applythespecified
lubricatingoiltotheslidingsurfaceofthepartsand
components.
Afterreassembling,checkwhetherallthespare
partsaremountedproperlybymeansofturning,
movingandoperatingthem.
4. Todisassembleandassembleamotorcycle,
specialservicetools(SST)andgeneral-purpose
toolsmustbeusedinaccordancewithrelevant
regulations.
5. Thespecifiedorequivalentlubricatinggrease(oil)
mustbeappliedtoorrefilledintothespecified
locations.
6. When2ormorepersonsarecarryingoutthe
operation,theyshallworkwitheachotherandpay
attentiontosafety.
7. Beforeoperating,alwaysremovethenegative(-)
endofthebatteryfirstandtakecaretopreventthe
wrenchorthelikefromtouchingtheframe.After
operating,reconfirmalltheconnections,fixings
andjunctions.Ifthebatteryisalreadyremoved,
connectthepositive(+)endfirst.

YG125-30B Maintenance Manual Overview
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8. Incasethefuseisblown,checkforthecausesand,
afterbeingrepaired,replacecorrespondingfuse
asperthespecifiedcapacity.
9. Thecapsmustbesecurelyputontheterminals
aftertheoperationiscomplete
10.Whiledisassemblingaconnectorjointswithlock,
releasethelockbeforeproceedingwithoperation.
Whiledisassemblingaconnectorjoints,holdthe
connectorbodywithoutpullingthewireharness.
Beforeconnectingtheconnector,theterminalsshallbe
freefrombreakingorbending.Makesuretheterminals
arenottoolongorarefallingoff.
Theconnectorshallbefullyinsertedinplace.
Foraconnectorwithlock,confirmwhetherthelockis
completelyfixed.
Makesuretheharnessisnotfallingoff
Makesuretheplasticjacketoftheconnectorissecurely
coveringtheconnectorwithoutscalingoff.
11.Beforeconnectingaconnector,makesurethe
sleeveisnotbrokenandtheopeningofthe
intermediateterminalisnottoolarge
Thejointshallbefullyinsertedinplace.
Makesuretheplasticjacketishousingtheterminal
completely.Theopeningoftheplasticjacketshallnot
faceup.
12.Theharnessfixingstrapshallfirmlybuttonthe
specifiedpositionontheframe.
Confirmcapacity! Crackle

YG125-30B Maintenance Manual Overview
4
13.Theclampshallreliablybitethewireharness
Incaseofaweldedclamp,itshallnotbitethewire
harnesstowardstheweldmark
Thewireharnessshallbeclampedattheposition
withoutcontactingarotatingpartoraremovingelement.
Thewireharnessshallbeclampedattheposition
withoutcontactingapartthatgenerateshigh
temperature.
Thewireharnessshallbeclampedattheposition
withoutcontactingtheedgeorsharpcornersofthe
vehiclebody.
Thewireharnessshallbeincapableofpassingthrough
thepositioncontactingabolt,ascrewheadoranyfront
part.
Thewireharnessshallnotbeslackenedorbeforcibly
pulled.
Ifthewireharnesshastocontacttheedgeorsharp
cornerparts,thecontactingpartshallbeprotectedwith
hoseoradhesivetape.
Incaseofawireharnesswithgarland,itshallbereliably
harnessed.
Donotdamagethegarnishofthewireharness.
Oncethewireharnessisdamaged,repairitbycoiling
withplasticadhesivetape.
Whilemountingpartsandcomponents,donotpressthe
wireharness.
Donotmountwireharnesswithittwisted.
Donottouch!
Donotpull!
Payattentionnottopressit.

YG125-30B Maintenance Manual Overview
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14.Whenwiring,notewhenturningitleftwardsor
rightwardstothelimitposition,thewireharness
shallnotbetighteneduporslackened,andmake
surethereisnosignificantbending,pressing,
interveningofmarginalparts.
15.Whileusingthetesttable,operateaccordingtothe
maintenancemanualafterunderstandingthe
explanationsintheinstructionmanual.
16.Donotdroporthrowthepartsandcomponents.
17.Incaseofrustontheterminals,carryout
connectionoperationafterdisposingitwith
abrasivepaper,etc.
18.Donotforciblytwistorforcefullybendthecable.
Becauseadeformedordamagedcableisthe
causeofbadoperationanddamage.
Rustmustbe
eliminated!
Haveyoulearnedbyheartthemethod
ofapplication?Arethemeasurement
rangeandpolarityinaccordancewith
theinstructionmanual?

YG125-30B Maintenance Manual Overview
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TechnicalDataofMainPerformance
Item Data
Dimension & Weight
Length
Width
Height
Wheelbase
Min.groundclearance
Completevehicleweight
2050mm
830mm
1075mm
1360mm
200mm
Non-loadedweight:128kg,Curbweight:136kg,
Vehicle body
Frametype
Rakeangle
Frontsuspensiondevice
Rearsuspensiondevice
FrontTiresize
RearTiresize
Frontwheelpressure
Rearwheelpressure
Frontbrake
Rearbrake
Fueltankvolume
Fuelgrade
Cradletype
26
spring&hydrauliccompositedamping
spring&hydrauliccompositedamping
110/90-17
130/80-17
Normallyloaded:225kPa,
Normallyloaded:225kPa,
Singledisctype ModelΦ276
Singledisctype ModelΦ220
12L
93#

YG125-30B Maintenance Manual Overview
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Driving system
Clutch
Clutchoperatingsystem
Variablespeedgear
Primaryreductionratio
Transmissiongearratio
Finalreductionratio
Gearshiftingmode
Wetclutch,coilclutch,paperfrictionwafer
Manualmechanical
5-speedconstantmesh
3.35
Ⅰ3.077
Ⅱ1.789
Ⅲ1.304
Ⅳ1.091
V0.929
3.333
Leftfootoperatedtoandbacktype
Sequence: I－N－Ⅱ－Ⅲ－Ⅳ-V
Engine
Mode
Cylinderbore Stroke
Cylinderdisplacement
Compressionratio
Max.power
Max.torque
Valveclearance(cold)
Valvedrivinggear
Airfilter
Coolingmethod
Lubricationmethod
Engineoilgrade
Engineoilchargevolume
Engineoilfilterelement
Electricmotorstarting
Idlespeed
Netweightofengine
Single-cylinder forceair –cooling 4-strokeengine
52.4mm ×57.9mm
125cc
9.0:1
6.8kw/7500rpm
9N.m/6500rpm
IN: 0.06-0.08
EX: 0.06-0.08
Chaindrive
Oilpaperfilter
forceair-cooling
PleaseapplyShell10W/40-SFengineoilinsummerand10W/30-SFin
winte
1L
Oilpaperfilter
Electric/footstart
1500±150r/min
28.5±1kg

YG125-30B Maintenance Manual Overview
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Electrical system
Electricgenerator
Accumulatorcapacity
Powersupplysystem
Fusiblecutout
Sparkplug
Sparkpluggap
Ignitioncoiltype
Fuelsupplymode
Ignitionmode
Ignitionadvanceangle
Ignitiontiming
Frontlamp
Turnlamp
Stop/Rear-positionlamp
permanentmagnetDCmagneto
12V7A.h
DCpowersupply,andtheelectricgeneratorisonlyusedtorecharge
theaccumulator
15A/10A
CPR8EA-9
0.7-0.9mm
Openmagneticcircuit
Electronicallyinjection,ECUcontrol
EMS
EMS
EMS
12V/35W/35W
Front:12V10W Rear:12V10W
12V21W/5W
StandardTorqueValues
ENGINE
Item Quantity Threaddiameter
(mm) Torquevalue(N.m) Threadlocker
Cylinderheadcoverconnectingbolt 13 8 8～12
Cylinderbolt 410 40～50
2 6 8～12
Valveadjustingscrewnut 4 10 8～12
Timingdrivensprocketbolt 2 7 7～11
Rocker-armshaftcover 2 14 24～28
Magnetoflywheelfasteningnut 1 12 38～45 LOCTITE243
Clutchfasteningnut 1 18 114～126 LOCTITE243
Primarydrivinggearfasteningnut 1 18 143～157 LOCTITE243
Oildrainplug 1 12 28～32