Yamaha MBK YQ100 Service Manual

YQ1005ME1-AE1'00SERVICEMANUAL

GENINFO1-2IMPORTANT INFORMATIONEAS00020IMPORTANT INFORMATIONPREPARATION FOR REMOVAL ANDDISASSEMBLY1.Before removal and disassembly, remove alldirt, mu

ENG4-20V-BELT, CLUTCH ANDSECONDARY/PRIMARY SHEAVE4. Attach :• Clutch spring holder Clutch spring holder :90890-013375. Remove :• Clutch securing nut

ENG4-212. Measure :• Clutch shoe thickness aOut of specification→Replace.Clutch shoe thickness :4 mm< Wear limit> :2.5 mmV-BELT INSPECTION1. Ins

ENG4-22V-BELT, CLUTCH ANDSECONDARY/PRIMARY SHEAVEPRIMARY SHEAVE INSPECTION1. Inspect :• Primary sliding sheave • Primary fixed sheave Wear/Cracks/Sc

ENG4-23SECONDARY SHEAVE INSPECTION1. Inspect :• Secondary fixed sheave • Secondary sliding sheave Scratch/Crack/Damage→Replace as a set.• Oil seal 

ENG4-24V-BELT, CLUTCH ANDSECONDARY/PRIMARY SHEAVESECONDARY SHEAVE INSTALLATIONWhen assembling the secondary sheave, re-verse the disassembly procedure

ENG4-25V-BELT, CLUTCH ANDSECONDARY/PRIMARY SHEAVE9. Tighten :• Nut (secondary sheave)Use sheave holder Sheave holder :90890-01701PRIMARY SHEAVE INST

ENG4-26V-BELT, CLUTCH ANDSECONDARY/PRIMARY SHEAVE6. Install :• Shim • Primary fixed sheave • Crow washer • One-way clutch • Conical spring washer

ENG4-27Order1234Q’ty1111STARTER CLUTCH AND STARTER MOTORSTARTER CLUTCH AND STARTER MOTORRemarksRemove the parts in order.Refer to “COVERS” in chapter

ENG4-28Order5678910Job name/Part nameStarter clutchPlain washerStarter wheel gearCollarStarter motorStarter motor connectorQ’ty121121RemarksReverse th

ENG4-29STARTER CLUTCH AND GEARS1. Inspect :• Starter clutchPush the dowel pin to arrow direction.Unsmooth operation→Replace starter clutchassembly.2.

GENINFO1-3IMPORTANT INFORMATIONCAUTION:EAS00023LOCK WASHERS / PLATES AND COTTERPINS1.After removal, replace all lock washers / plates and cott

ENG4-30Order12345678Q’ty11/1112111C.D.I. MAGNETOC.D.I. MAGNETORemarksRemove the parts in order.Refer to “BATTERY COVER ANDLOWER COVER” section in chap

ENG4-31C.D.I. MAGNETO REMOVAL1. Remove :• Nut  (rotor)• Plain washerNOTE:Hold the rotor to loosen the nut by the flywheelholding tool .Flywheel hold

ENG4-32Order12345678Q’ty11111111AUTOLUBE PUMPAUTOLUBE PUMPRemarksRemove the parts in order.Refer to “C.D.I. MAGNETO” section.Refer to “AUTOLUBE PUMP I

ENG4-33AUTOLUBE PUMPAUTOLUBE PUMP INSTALLATIONAfter installing autolube pump, it must bebleeded.1. Install :• Pin • Pump drive gear • Circlip 2. Ap

ENG4-34Order1234567Q’ty1121111TRANSMISSIONTRANSMISSIONRemarksRemove the parts in order.Refer to “REAR WHEEL AND REARBRAKE ” section in chapter 6.Refer

ENG4-35TRANSMISSIONTRANSMISSION18Nm(1.8kg.m)T R..12Nm(1.2kg.m)T R..12345678910TRANSMISSIONBOrder8910Job name/Part nameCirclipMain axleDrive axleQ’ty11

ENG4-36EAS00423CHECKING THE TRANSMISSION1.Measure:•main axle runout (with a centering device and dial gauge)Out of specification → Replace the main a

ENG4-379Nm(0.9kg.m)T R..12Nm(1.2kg.m)T R..34126578109Order Q’tyCRANKCASE AND REED VALVECRANKCASE AND REED VALVECRANKCASE AND REED VALVERemarksRemove t

ENG4-389Nm(0.9kg.m)T R..12Nm(1.2kg.m)T R..34126578109CRANKCASE AND REED VALVECRANKCASE AND REED VALVECRANKCASE AND REED VALVEBOrder12345678910Job name

ENG4-392. Attach :• Crankcase separating tool Crankcase separating tool :90890-01135NOTE:Fully tighten the tool holding bolts, but makesure the tool

GENINFO1-4CHECKING THE CONNECTIONS+-+-EAS00026CHECKING THE CONNECTIONSCheck the leads, couplers, and connectors forstains, rust, moisture, etc.1.Disc

ENG4-40CRANKCASE (RIGHT) INSTALLATION1. Install :• Dowel pins • Engine mount spacer 2. Apply :• Yamaha Bond No.1215 To the mating surfaces of both

ENG4-41CRANKCASE AND REED VALVE8. Install :• Gasket• Reed valve  11 Nm(1.1 kg.m)T R..

ENG4-42Order1234Q’ty1221CRANKSHAFTRemarksRemove the parts in order.Refer to “CRANKCASE AND REEDVALVE” section.Reverse the removal procedure for insta

ENG4-43CRANKSHAFTCRANKSHAFT REMOVAL1. Attach :• Crankcase separating tool Crankcase separating tool :90890-011352. Remove :• Crankshaft CRANKSHAFT I

ENG4-44CRANKSHAFT INSTALLATION1. Attach :• Crankshaft Installing ToolCrankshaft installing tool:90890-0127490890-0127590890-0127790890-012882. Insta

5CARB

CARBCHAPTER 5.CARBURETORCARBURETOR...5-1CARBURETOR ...

CARB5-1CARBURETOROrderJob/Part Q'tyRemoving the carburetorAir filter box1 Fuel hose 12 Vacuum hose 13 Oil delivery hose 14 Choke cable 15 Air fil

CARB5-2CARBURETORCarburetor disassemblyQ Carburetor top 1W Gasket 1E Throttle valve spring 1R Needle set 1T Throttle valve 1Y Starter retaining plate

CARB5-3w Float chamber 1e Float chamber gasket 1r Float pin 1t Float / Needle valve 1/1y Main jet 1u Main nozzle 1i Pilot jet 1o Carburetor body 1Orde

GENINFO1-5HOW TO USE THE CONVERSION TABLEHOW TO USE THE CONVERSION TABLEAll specification data in this manual are listed in SI and METRIC UNITS.Use th

CARB5-4CARBURETOREAS00485CHECKING THE CARBURETOR1.Check :•carburetor body 햲•float chamber•jet housing•fuel passagesDurt/Obstruction → CleanCracks/dama

CARB5-5322018햲햳햳햴햴햵CARBURETOR6.Check :•Throttle valve free movementUnsmooth/Stickiness → Replace.Insert the throttle valve 햲 into the carburetorbody 햳

CARB5-6CARBURETOR2.Install :•throttle valve 햲•starter plungerNOTE:Align the groove 햳 of the throttle valve with theprojection 햴 of the carburetor.3.In

CARB5-7352001햲322031햲FUEL COCKFUEL COCKINSPECTING THE FUEL COCK1.Stop the engine.2.Remove:• Side coversRefer to "COVERS" in Chapter 3.3.Insp

CARB5-8Removing the reed valveCarburetor1 Carburetor joint 12 Reed valve assembly 1OrderJob/Part Q'tyRemarksREED VALVEREED VALVEFor installation

CARB5-9REED VALVEYP600051CHECKING THE REED VALVE1.Inspect :• Caburetor jointDamage/Cracks → Replace.• Reed valveFatigue/Cracks → Replace.*************

6CHAS

CHASCHAPTER 6.CHASSISFRONT WHEEL AND BRAKE DISC...6-1FRONT WHEEL AND BARKE DISC ...

CHASFRONT FORK...6-30REMOVING THE FRONT FORK LEGS ...

CHAS6-1FRONT WHEEL AND BRAKE DISCOrderRemoving the front wheel and brakediscI Disconnect:1 Speedometer cable 1II Remove:2 Front brake caliper 13 Wheel

GENINFO1-6SPECIAL TOOLSCrankshaft installer pot Crankshaft installer bolt Adapter Spacer These tools are used to install the crank-shaft.Flywh

CHAS6-2FRONT WHEEL AND BRAKE DISCOrderDisassembling the front wheelI Remove:1 Oil seal 12 Bearing 23 Collar 1Remove the parts in the order listed.Refe

CHAS6-3FRONT WHEEL AND BRAKE DISCEAS00520REMOVING THE FRONT WHEEL1.Stand the motorcycle on a level surface.Securely support the motorcycle so that t

CHAS6-4FRONT WHEEL AND BRAKE DISCa.Clean the outside of the front wheel hub.b.Remove the oil seal  with a flat-headscrewdriver.NOTE:To prevent damagi

CHAS6-5FRONT WHEEL AND BRAKE DISC4.Check:• Wheel bearingsFront wheel turns roughly or is loose → Replacethe wheel bearings.• Oil sealsDamage/wear → Re

CHAS6-6FRONT WHEEL AND BRAKE DISCEAS00528CHECKING THE BRAKE DISC1.Check:• Brake discDamage/galling → Replace.2.Measure:• Brake disc deflectionOut of s

CHAS6-7FRONT WHEEL AND BRAKE DISCBrake disc bolt23 Nm (2.3 m • kg)d.Measure the brake disc deflection.e.If out of specification, repeat the adjustment

CHAS6-8EAS00542*INSTALLING THE FRONT WHEEL1.Lubricate:• Wheel axle• Wheel bearings• Oil seal lips• Speedometer drive gear• Speedometer driven gearReco

CHAS6-9EAS00548ADJUSTING THE FRONT WHEEL STATICBALANCENOTE:• After replacing the tire, wheel or both, the frontwheel static balance should be adjusted

CHAS6-103.Adjust:• Front wheel static balancea.Install a balancing weight  onto the rimexactly opposite the heavy spot “X”.NOTE:Start with the lighte

CHAS6-11REAR WHEEL AND BRAKEEAS00555REAR WHEEL AND BRAKEOrderRemoving the rear wheel andthe rear brakeLower coverExhaust pipeI Remove:1 Rear axle nut

GENINFO1-7SPECIAL TOOLSTool N° Tool name/usage IllustrationRing nut wrench Steering nut wrench These tools are used to loosen and tightenthe steerin

CHAS6-12REAR WHEEL AND BRAKEOrderQ'tyJob/PartRemarks8 Pin 19 Camshaft lever 110 Wear indicator 111 Brake camshaft 1For installation, reverse the

CHAS6-13346007@REAR WHEEL AND BRAKEEAS00565CHECKING THE REAR WHEEL1.Check:• Wheel axle• Rear wheelRefer to "FRONT WHEEL".2.Check:• Tire• R

CHAS6-14346008aREAR WHEEL AND BRAKEINSTALLING THE REAR BRAKEReverse the removal procedure.Note the following points.1.Install:• Brake camshaft NOTE:A

CHAS6-15INSTALLING THE REAR WHEELReverse the removal procedure.Note the following points.1.Clean:• Rear wheel axle2.Install:• Rear wheel• Plain washer

CHAS6-16FRONT BRAKEEAS00576FRONT BRAKEFRONT BRAKE PADSOrderRemoving the front brake padsI Remove:1 Plastic cap 12 Retaining clip 13 Retaining pin 14 P

CHAS6-17FRONT BRAKERecommanded brake component replacementschedule:Brake pads If necessaryBrake hose Every two yearsBrake fluidEvery two years or when

CHAS6-18@BRAKE PADS REPLACEMENTNOTE:It is not necessary to disassemble the brakecaliper and brake hose to replace the brakepads.1.Remove:• Brake padsN

CHAS6-19OrderRemoving the front brake mastercylinderDrain the brake fluidHandlebar coversI Remove:1 Brake switch 12 Brake lever 13 Union bolt 14 Coppe

CHAS6-20FRONT BRAKEEAS00585OrderDisassembling the master cylinderI Remove:Q Master cylinder cap 1W Diaphragm 1II Remove:E Dust boot 1R Actuator 1T Act

CHAS6-21EAS00588DISASSEMBLING THE FRONT BRAKEMASTER CYLINDERNOTE:• Before disassembling the front brake mastercylinder, drain the brake fluid from the

2SPEC

CHAS6-22FRONT BRAKEEAS00596ASSEMBLING AND INSTALLING THEFRONT BRAKE MASTER CYLINDER• Before installation, all internal brakecomponents should be clean

CHAS6-23FRONT BRAKE4.Fill:• brake master cylinder reservoir(with the specified amount of the recommendedbrake fluid)Recommended brake fluidDOT #3 or D

CHAS6-24FRONT BRAKEOrderRemoving the front brake caliperDrain the brake fluidI Remove:1 Union bolt 12 Copper washer 13 Brake hose 14 Copper washer 1II

CHAS6-25FRONT BRAKEEAS00614OrderRemove the parts in the order listed.Refer to "REMOVING THE FRONTBRAKE PADS".Refer to "DISASSEMBLING TH

CHAS6-26FRONT BRAKEEAS00620DISASSEMBLING THE FRONT BRAKECALIPERNOTE:Before disassembling the brake caliper, drainthe brake fluid from the entire brake

CHAS6-27FRONT BRAKEEAS00631CHECKING THE FRONT BRAKE CALIPERRecommanded brake component replacementschedule:Brake pads If necessaryBrake hose Every two

CHAS6-28FRONT BRAKEEAS00635INSTALLING THE FRONT BRAKE CALIPERBefore installation, all internal brakecomponents should be cleaned andlubricated with cl

CHAS6-294.Fill:• brake master cylinder reservoir(with the specified amount of the recommendedbrake fluid)Recommended brake fluidDOT #3 or DOT #4• Use

CHAS6-30EAS00646FRONT FORKFRONT FORKOrderRemove the parts in the order listed.Refer to "FRONT WHEEL AND BRAKEDISC".Refer to "REMOVING T

CHAS6-31FRONT FORKOrderRemove the parts in the order listed.Refer to "ASSEMBLING THE FRONTFORK LEGS".For installation, reverse the removal p

SPECCHAPTER 2.SPECIFICATIONSGENERAL SPECIFICATIONS ...2-1MAINTENANCE SPECIFICATIONS

CHAS6-32FRONT FORKWARNING REMOVING THE FRONT FORK LEGSThe following procedure applies to both of thefront fork legs.1.Stand the scooter on a level sur

CHAS6-33FRONT FORK4.Remove:• damper rod assembly boltNOTE:While holding the damper rod assembly with thedamper rod holder  and T-handle , loosenthe

CHAS6-34FRONT FORK3.Check:• damper rod Damage/wear → Replace.Obstruction → Blow out all of the oil passageswith compressed air.• oil flow stopper Da

CHAS6-35FRONT FORKDamper rod holder90890-01294T-handle90890-013264.Install:• oil seal (with the fork seal driver weight  and forkseal driver attach

CHAS6-36FRONT FORKNOTE:• While filling the front fork leg, keep it upright.• After filling, slowly pump the front fork leg upand down to distribute th

CHAS6-37HANDLEBARHANDLEBAROrderRemove the parts in the order listed.Refer to "COVERS" in Chapter 3.Refer to "MASTER CYLINDER".Refe

CHAS6-38HANDLEBAROrderRefer to "INSTALLING THE HANDLE-BAR".For installation, reverse the removal pro-cedure.Q'tyJob/PartRemarks6 Handle

CHAS6-39EAS00666REMOVING THE HANDLEBAR1.Stand the scooter on a level surface.Securely support the scooter so that there isno danger of it falling over

CHAS6-40EAS00673INSTALLING THE HANDLEBAR1.Stand the scooter on a level surface.Securely support the scooter so that there isno danger of it falling ov

CHAS6-41HANDLEBAR7.Install:• right handlebar switchMake sure the throttle grip operates smoothly.NOTE:Align the projection on the right handlebar swit

SPEC2-1GENERAL SPECIFICATIONSSPECIFICATIONSGENERAL SPECIFICATIONSDimensions:Overall length 1,762 mmOverall width 690 mmOverall height 1,151 mmSeat hei

CHAS6-42STEERING HEADEAS00675STEERING HEADOrderRemove the parts in the order listed.Securely support the scooter so thatthere is no danger of it falli

CHAS6-43OrderRefer to "REMOVING THE LOWERBRACKET".For installation, reverse the removal proce-dure.Q'tyJob/PartRemarksSTEERING HEAD7 Ba

CHAS6-44STEERING HEADWARNING EAS00680REMOVING THE LOWER BRACKET1.Stand the scooter on a level surface.Securely support the scooter so that there isno

CHAS6-45STEERING HEADEAS00684INSTALLING THE STEERING HEAD1.Lubricate:• upper bearing• lower bearing• bearing racesRecommended lubricantLithium soap ba

CHAS6-46REAR SHOCK ABSORBER ASSEMBLYOrderRemove the parts in the order listed.Refer to "COVERS" in chapter 3.For installation, reverse the r

CHAS6-47EAS00695CHECKING THE REAR SHOCK ABSORBERASSEMBLY1. Check:• rear shock absorber rodBends/damage → Replace the rear shockabsorber assembly.• re

7ELEC

ELECCHAPTER 7.ELECTRICALCIRCUIT DIAGRAM ...7-1ELECTRICAL COMPONENTS

ELEC7-1ELECTRICALCIRCUIT DIAGRAMCIRCUIT DIAGRAM--MLOCKOFFCHECKON(RED)(RED)BrBrBrLRGyGyGyGYBBGyBBLRGYBRRBrRBW BW BWGyBrRBBWBWOrOrBBOrBBBRBRGWGWWRWRWL

ELEC7-2COLOR CODEQ CDI magnetoW CDI unitE Ignition coilR Spark plugT Main switchY FuseU BatteryI Rectifier/regulatorO Starter relayP Starter motor{ Ri

SPEC2-2GENERAL SPECIFICATIONSSpark plug:Type BR8HSManufacturer NGKGap 0.5 ~ 0.7 mmClutch type: Dry, centrifugal automaticTransmission:Primary reductio

ELEC7-3ELECTRICAL COMPONENTSELECTRICAL COMPONENTSQ Wire harnessW Fuel senderE Starter relayR Ignition coilT CDI unitY Oil senderU BatteryI Resistance햲

ELEC7-4햲햳햴햵Q Main switchW Flasher relayE HornR Rectifier/RegulatorELECTRICAL COMPONENTS

ELEC7-5"∞""Ω x 1""0"SWITCH INSPECTIONSWITCH INSPECTIONUse a pocket tester to check the terminals forcontinuity. If the c

ELEC7-6SWITCH CONTINUITY INSPECTIONBefore checking a switch refer to the checkingswitches as shown in the page 7-5 and checkfor the correct terminal c

ELEC7-7--MLOCKOFFCHECKON(RED)(RED)BrBrBrLRGyGyGyGYBBGyBBLRGYBRRBrRBW BW BWGyBrRBBWBWOrOrBBOrBBBRBRGWGWWRWRWLWLWWYRYRWYRWYRYRRWBYRRBRRLWBGYLWGYLWGYR

ELEC7-8IGNITION AND STARTING SYSTEMTROUBLESHOOTINGTHE STARTING SYSTEM DOES NOTWORK (NO SPARK OR IRREGULARSPARKS)Procedure:Check:1. Fuse (main)2. Batte

ELEC7-9IGNITION AND STARTING SYSTEM4.Spark check• Remove the spark plug cap.• Connect the ignition checker 햲햳 Ground a Spark plug gap• Turn the main s

ELEC7-10IGNITION AND STARTER SYSTEM6.Ignition coil resistance• Disconnect the ignition coil leads.• Connect the pocket tester (Ωx1) to the igni-tion c

ELEC7-11IGNITION AND STARTING SYSTEM9.Main switchRefer to "SWITCH INSPECTION" section.10.Connections• Check all connections in the ignition

ELEC7-12IGNITION AND STARTING SYSTEMTROUBLESHOOTINGSTARTER MOTOR DOES NOT WORKProcedureCheck:1. Fuse (main)2. Battery3. Starter motor4. Starter relayN

YQ100SERVICE MANUAL© 2000 by MBK INDUSTRIE1st Edition, February 2000All rights reserved. Anyreprinting or unauthorized usewithout the writtenpermissio

SPEC2-3Wheel travel:Front 80 mmRear 72 mmElectrical:Ignition system CDICharging system Flywheel magnetoBattery type/model YT4L-BSBattery capacity 12V

ELEC7-13IGNITION AND STARTER SYSTEMWORKSReplace the starter relay.4.Starter relay• Disconnect Blue/White lead from the wireharness.• Connect the (-) t

ELEC7-14STARTER MOTOROrderJob name/Part nameQ'tyRemarksStarter motor removalStater motor disassembly햲 O-ring 1햳 Front bracket 1햴 Rubber seal 1햵 B

ELEC7-15STARTER MOTORINSPECTION1.Check:• CommutatorDirty → Clean it with #600 grit sandpaper.2.Measure:• Commutator diameter @Out of specification → R

ELEC7-16STARTER MOTOR6.Measure:• Brush spring forceFatigue/Out of specification → Replace as aset.Brush spring force:563 ~ 844 g5.Measure:• Brush leng

ELEC7-17--MLOCKOFFCHECKON(RED)(RED)BrBrBrLRGyGyGyGYBBGyBBLRGYBRRBrRBW BW BWGyBrRBBWBWOrOrBBOrBBBRBRGWGWWRWRWLWLWWYRYRWYRWYRYRRWBYRRBRRLWBGYLWGYLWGYR

ELEC7-18CHARGING SYSTEMTROUBLESHOOTINGTHE BATTERY IS NOT CHARGEDProcedureCheck:1. Fuse (main)2. Battery3. Charging voltage4. Charging coil resistance5

ELEC7-19CHARGING SYSTEM3. Charging voltage• Connect the engine tachometer to the sparkplug lead.• Connect the pocket tester (DC20V) to thebattery term

ELEC7-20CHARGING SYSTEM4. Charging coil resistance• Disconnect the CDI magneto coupler fromthe wire harness.• Connect the pocket tester (Ω x 1) to the

ELEC7-21--MLOCKOFFCHECKON(RED)(RED)BrBrBrLRGyGyGyGYBBGyBBLRGYBRRBrRBW BW BWGyBrRBBWBWOrOrBBOrBBBRBRGWGWWRWRWLWLWWYRYRWYRWYRYRRWBYRRBRRLWBGYLWGYLWGYR

ELEC7-22LIGHTING SYSTEMTROUBLESHOOTINGTHE HEADLIGHT, HEADLIGHTINDICATOR, POSITION LIGHT, METERLIGHT, LICENSE LIGHT AND/ORTAILLIGHT DO NOT WORKProcedur

SPEC2-4Cylinder head:Warp limit *** 0.02 mm* Lines indicate straight edgemeasurements.Cylinder:Bore size 52.002 ~ 52.012 mm ***Taper *** 0.05 mmPiston

ELEC7-23YP8020181."LIGHTS" switchRefer to "SWITCH INSPECTION" section.NO CONTINUITYLIGHTING SYSTEM2.Lighting coil resistance• Dis

ELEC7-24LIGHTING SYSTEMThere is a defect in the wire harness betweenthe main switch and the bulb socket connector→ Repair.MEETSSPECIFICATIONOUT OF SPE

ELEC7-25LIGHTING SYSTEM2.Voltage• Connect the pocket tester (AC 20 V) to thefront position light connectors.Pocket tester (+) lead → → → → → Blue/Red

ELEC7-26LIGHTING SYSTEM4.The taillight does not work.1.Bulb and socket.Refer to " SWITCH INSPECTION " section.2.Voltage• Connect the pocket

ELEC7-272.Voltage• Connect the pocket tester (AC 20 V) to thelicense light coupler.Pocket tester (+) lead →→→→→ Blue/Red 햲Pocket tester (-) lead →→→→→

ELEC7-28SIGNAL SYSTEM--MLOCKOFFCHECKON(RED)(RED)BrBrBrLRGyGyGyGYBBGyBBLRGYBRRBrRBW BW BWGyBrRBBWBWOrOrBBOrBBBRBRGWGWWRWRWLWLWWYRYRWYRWYRYRRWBYRRBRRL

ELEC7-29SIGNAL SYSTEMTROUBLESHOOTINGFLASHER LIGHTS, TAIL/BRAKE LIGHT,"OIL" WARNING LIGHT DO NOT WORK.HORN DOES NOT SOUND, FUEL METERDOES NOT

ELEC7-30SIGNAL SYSTEM4.Connections• Check all connections in the signal system.Refer to "WIRE DIAGRAM".CONTINUITYCheck the condition of eac

ELEC7-31SIGNAL SYSTEMSIGNAL SYSTEM CHECK1. Horn does not sound.1."HORN" switchRefer to "SWITCH INSPECTION".CONTINUITY2.Voltage• Co

ELEC7-32SIGNAL SYSTEM2. The brake light does not work.1.Bulb and socket.Refer to "SWITCH INSPECTION".CONTINUITY2.Brake switchRefer to "

SPEC2-5MAINTENANCE SPECIFICATIONSCrankshaft:Crank width “A” 37.90 ~ 37.95 mm ***Runout limit “C” *** 0.03 mmConnecting rod length 79.9 ~ 80.1 mmSide c

ELEC7-33SIGNAL SYSTEM3.Flashers and flasher indicator do not work.1.Bulb and socketRefer to "SWITCH INSPECTION".CONTINUITY2.Flasher switchRe

ELEC7-34SIGNAL SYSTEM5.Voltage• Connect the pocket tester (DC 20 V) to theflasher coupler.Left flasher bulbPocket tester (+) lead →→→→→ Chocolate 햲Poc

ELEC7-35SIGNAL SYSTEM3. Voltage• Connect the pocket tester (DC20V) to thebulb socket connectorPocket tester (+) lead →→→→→ Grey 햲Pocket tester (-) lea

8TRBLSHTG

TRBLSHTGCHAPTER 8.TROUBLESHOOTINGSTARTING FAILURE/ HARD STARTING ...8-1FUEL SYSTEM ...

TRBLSHTG8-1STARTING FAILURE/HARD STARTINGTROUBLESHOOTINGNOTE:The following troubleshooting does not cover all the possible causes of trouble. It shoul

TRBLSHTG8-2STARTING FAILURE/HARD STARTING/POOR IDLE SPEED PERFORMANCECOMPRESSION SYSTEMCylinder and cylinder head Crankcase and crankshaft• Loose spar

TRBLSHTG8-3POOR MEDIUM AND HIGH SPEED PERFORMANCE/FAULTY AUTOMATICPOOR MEDIUM AND HIGH SPEED PERFORMANCEFUEL SYSTEMFuel tank Carburetor• Clogged fuel

TRBLSHTG8-4FAULTY AUTOMATIC/OVER HEATINGOVER HEATINGOVER HEATINGIgnition system Engine oil• Improper spark plug gap • Improper engine oil quality (hig

TRBLSHTG8-5IMPROPER KICKING/FAULTY BRAKEIMPROPER KICKINGSLIPPINGKick axle assembly Transmission oil• Low tension of kick clip • Improper quality (low

SPEC2-6MAINTENANCE SPECIFICATIONSModel Standard LimitReed valve:Valve stopper height 6.0 ~ 6.4 mm ***Reed Valve Clearance Less than 0.2 mm ***Lubricat

TRBLSHTG8-6FRONT FORK OIL LEAKAGE AND FRONT FORKMALFUNCTION/INSTABLE HANDLINGINSTABLE HANDLINGINSTABLE HANDLINGHandlebar Wheels• Improperly installed

TRBLSHTG8-7FAULTY SIGNAL AND LIGHTING SYSTEMFlasher winks slower Horn is inoperative• Faulty flasher relay • Faulty battery• Insufficient battery capa

YQ100 WIRING DIAGRAMQ C.D.I. magnetoW C.D.I. unitE Ignition coilR Spark plugT Main switchY FuseU BatteryI Rectifier / regulatorO Starter relayP Starte

SPEC2-7TIGHTENING TORQUESENGINETighteningPart to be tightened Part Thread Q'ty torque Remarksname sizeNm m.kgSpark plug - M14 1 20 2.0Head cylind

SPEC2-8MAINTENANCE SPECIFICATIONSSteering system:Steering bearing type Ball bearing ***Size of steel balls x qty:Upper ø4.75 mm x 15 ***Lower ø4.75 m

SPEC2-9MAINTENANCE SPECIFICATIONSModel Standard LimitFront disk brake:Type Single disc ***Diameter and thickness 190.0 x 3.5 mm ***Pad thickness 4.5 m

SPEC2-10MAINTENANCE SPECIFICATIONSTIGHTENING TORQUESCHASSISTighteningPart to be tightened Thread torque Remarkssize Nm m.kgFrame with engine bracket M

SPEC2-11MAINTENANCE SPECIFICATIONSTighteningPart to be tightened Thread torque Remarkssize Nm m.kgScrews tapping in plastic Ø5 3.2 0.32Screws tapping

SPEC2-12MAINTENANCE SPECIFICATIONSELECTRICALVoltage: 12 V ***Ignition system:Ignition timing(B.T.D.C.) 14° at 5000 r/min ***Ignition timing type Const

CAUTION:WARNING NOTICEThis manual was written by the MBK INDUSTRIE primarily for use by YAMAHA and MBK dealersand their qualified mechanics. It is not

SPEC2-13Model Standard LimitBattery :Specific gravity 1.280 ***Starter motor:Model / Type MORYAMAOutput 0.14 kW ***Armature coil resistance 0.06 ~ 0.0

SPEC2-14GENERAL TORQUE SPECIFICATIONSBAA B General torque(Nut) (Bolt) specificationsNm m.kg10 mm 6 mm 60 0.612 mm 8 mm 15 1.514 mm 10 mm 30 3.017 mm 1

SPEC2-15LUBRICATION POINTS AND LUBRICANT TYPESLubrication point Lubricant typeOil seal lipsO-ringCrankshaft bearingsNeedle bearings (connecting rod)Ma

SPEC2-16LUBRICATION POINT AND GRADE OF LUBRICANTLubrication point Lubricant typeFront wheel oil seal (right/left)Rear wheel oil sealSteering bearing a

SPEC2-17CABLE ROUTING햲 Taillight햳 Rear left flasher light햴 Seat lock assy'햵 Band switch햶 Clip햷 Starter relay햸 Fuse햹 Battery assy'햺 Ignition

SPEC2-18CABLE ROUTINGA Untight the seat lock plate to give to the seat lock cable more free play. Tight the seat lock cable at 1 1/2turn.B Fix on the

SPEC2-19CABLE ROUTINGQ Fuel senderW C.D.I. unitE Band switchR Oil level senderT Wire cylinder assy'Y Rectifier / RegulatorU Band switch cordonI M

SPEC2-20CABLE ROUTINGA Fix the wire harness, starter motor wire and the flywheel wire all together.B Fix the wire harness.C Pass the wire harness betw

SPEC2-21CABLE ROUTING햲 Resistor assy'햳 Horn햴 Band switch햵 Frame햶 Front brake hose햷 Speedometer cable햸 Gear unit assy'햹 Front mudguard햺 Front

SPEC2-22CABLE ROUTING햲 Right hand grip햳 Master cylinder햴 Speedometer assy'햵 Left hand grip햶 Rear brake lever햷 Rear brake cable햲햳햵햶햵햶햷햸햹햺햻햽햾햾햲햳 햴햴

ENGENGCDI MAGNETOCDI magneto, Rotor, Startor removalSeat coverSide coversFootrest board1 Fan cover 12 Fan 13 Nut 14 Washer 15 Magneto rotor 16 Woodruf

SPEC2-23CABLE ROUTINGA Fix the wire harness on the frame bracket.B Group all connection in this area.C Pass the starter cable through the hole.D Tight

SPEC2-24햲 Speedometer cable햳 Wire harness햴 Front brake hose햵 Rear brake cable햶 Front handlebar cover햷 Speedometer cover햸 Speedometer햹 Rear handlebar c

3CHKADJ

CHKADJCHAPTER 3.PERIODIC CHECKS AND ADJUSTMENTSPERIODIC MAINTENANCE AND LUBRICATION... 3-1COVERS ...

INSPREG3-1PERIODIC MAINTENANCE AND LUBRICATIONPERIODIC CHECKS AND ADJUSTMENTSEAS00036PERIODIC CHECKS AND ADJUSTMENTSINTRODUCTIONThis chapter includes

INSPREG3-2PERIODIC CHECKS AND ADJUSTMENTSNOTE:• The air filter needs more frequent service if you are riding in unusually wet or dusty areas.• Brake f

INSPREG3-3COVERSSEAT AND SIDE COVERSOrder Job/Part Q’ty Remarks125 344T.R2 Nm (0,2 m.kg) T.R3 Nm (0,3 m.kg) T.R8 Nm (0,8 m.kg) T.R8 Nm (0,8 m.kg

INSPREG3-4COVERSBOX, LOWER SIDE COVERS AND MUDGUARD453312 T.R2,5 Nm (0,25 m.kg) T.R6 Nm (0,6 m.kg) T.R3 Nm (0,3 m.kg) T.R8 Nm (0,8 m.kg) Removing

INSPREG3-5COVERSOrderRemoving the frame reinforcement,fuel tank and rear under cover.Rear side coversSeatRemove the parts in the order listed.Refer to

INSPREG3-6COVERSOrderRemoving the front coversI Disconnect:Headlight lead 1II Remove:1 Front cover and headlight 12 Front fender 13 Front inner panel

INSPADJELECGENINFOENGCARBCHASSPECQWRETYUIOP{}qweryoptuiT.RTRBLSHTG[]BLSMEAS00009SYMBOLSThe following symbols are not relevant to everyvehicle.Symbols

INSPREG3-7OrderRemoving the handlebar coversI Untighten:Handlebar under cover 햲II Disconnect:Speedometer lead 1Wires and leadsIII Remove:1 Handlebar c

INSPREG3-8OrderRemoving the battery cover andlower cover.SeatBox and side coversFront coversI Remove:1 Battery cover 12 Lower cover 1Remove the parts

INSPREG3-9COVERSOrderRemoving the inner panel andfootrest board.I Remove:1 Inner panel 12 Footrest board 1Remove the parts in the order listed.NOTE:To

INSPREG3-10COVERSNOTE:Correct routing of cables and wires is essential for a safe operation of this scooter. Refer to the section“CABLE ROUTING” in Ch

INSPREG3-11ADJUSTING THE ENGINE IDLING SPEEDEAS00054ENGINEADJUSTING THE ENGINE IDLING SPEEDFor safety reasons, place the scooter on thecenterstand bef

INSPREG3-12ADJUSTING THE THROTTLE CABLE FREE PLAY@EAS00058ADJUSTING THE THROTTLE CABLE FREEPLAYNOTE:Prior to adjusting the throttle cable free play, t

INSPREG3-13햳햲Handlebar sidea.Loosen the locknut.b.Turn the adjusting nut in direction left or rughtuntil the specified throttle cable free play isobta

INSPREG3-14햲CHECKING THE SPARK PLUG5.Clean:•spark plug(with a spark plug cleaner or wire brush)6.Measure:•spark plug gap 햲(with a wire gauge or feeler

INSPREG3-15CHECKING THE ENGINE OIL LEVELEAS00070CHECKING THE ENGINE OIL LEVEL1.Inspect:•oil levelOil level low → Add oil to proper level asfollows.햲 &

INSPREG3-16CHANGING THE TRANSMISSION OIL/AUTOLUBE PUMP AIR BLEEDINGCHANGING THE TRANSMISSION OIL1.Remove:•drain plug 햲•oil filler plug 햳Drain the tran

EAS00011TABLE OF CONTENTSGENERAL INFORMATIONSPECIFICATIONSPERIODIC CHECKS ANDADJUSTMENTSENGINECARBURETORCHASSISELECTRICAL SYSTEMTROUBLESHOOTING1234567

INSPREG3-17AUTOLUBE PUMP AIR BLEEDING/CLEANING THE AIR FILTER ELEMENTEAS00089CLEANING THE AIR FILTER ELEMENT1.Remove:•air cleaner case cover 햲Never op

INSPREG3-18CLEANING THE AIR FILTER ELEMENT/CHECKING THE EXHAUST PIPE SYSTEMb. Squeeze excess solvent out of the elementand let dry.Do not twist the el

INSPREG3-19ADJUSTING THE FRONT BRAKE/ADJUSTING THE REAR BRAKEEAS00108CHASSISADJUSTING THE FRONT BRAKE1.Check:•brake lever free play @Out of specificat

INSPREG3-20CHECKING THE BRAKE FLUID LEVELEAS00116CHECKING THE BRAKE FLUID LEVEL1.Stand the scooter on a level surface.NOTE:• Place the scooter on a su

INSPREG3-21346002(a)햲햲햳CHECKING THE FRONT BRAKE PADS/CHECKING THE BRAKE SHOES/BLEEDING THE HYDRAULIC BRAKE SYSTEM햲EAS00126CHECKING THE BRAKE SHOES1.Op

INSPREG3-22BLEEDING THE HYDRAULIC BRAKE SYSTEM /CHECKING AND ADJUSTING THE STEERING HEADWARNING i. Repeat steps (e) to (h) until all air bubbleshave b

INSPREG3-23Steering nut wrench90890-01403Lower ring nut (initial tighteningtorque)38 Nm (3.8 m•kg)c.Loosen the lower ring nut 햶 of 1/4 turn andthen ti

INSPREG3-245.Install:•front coverRefer to "FRONT COVER"•HandlebarRefer to "HANDLEBAR" in chapter 6.Handlebar holder bolt60 Nm (6.0

INSPREG3-25EAS00165CHECKING THE TIRESThe following procedure applies to both of thetires.1.Measure:•tire pressureOut of specification → Regulate.The t

INSPREG3-26Minimum tire tread depth0.8 mm햲 Tire tread depth햳 Side wall햴 Wear indicatorDo not use a tubeless tire on a wheel designedonly for tube tire

1GENINFO

INSPREG3-27CHECKING THE WHEELS/CHECKING AND LUBRICATING THE CABLESEAS00168CHECKING THE WHEELSThe following procedure applies to both of thewheels.1.Ch

INSPREG3-28LUBRICATING THE CENTERSTAND/LUBRICATING THE REAR SUSPENSIONEAS00173LUBRICATING THE CENTERSTANDLubricate the pivoting point and metal-to-met

INSPREG3-29CHECKING THE BATTERYEAS00177ELECTRICAL SYSTEMCHECKING THE BATTERYBatteries generate explosive hydrogen gasand contain electrolyte which is

INSPREG3-304.Check:•electrolyte levelThe electrolyte level should be between theminimum level mark 햳 and the maximumlevel mark 햲.Below the minimum lev

INSPREG3-31• Make sure the battery charger lead clipsare in full contact with the battery terminaland that they are not shorted. A corrodedbattery cha

INSPREG3-32CHECKING THE BATTERY/CHECKING THE FUSEEAS00181CHECKING THE FUSEThe following procedure applies to all of thefuses.To avoid a short circuit,

INSPREG3-333.Replace:• blown fuse 햲a.Set the main switch to “OFF”.b.Install a new fuse of the correct amperage.c.Set on the switches to verify if the

INSPREG3-34REPLACING THE HEADLIGHT BULB/ ADJUSTING THE HEADLIGHT BEAMCAUTION:4.Install:•headlight bulb Secure the new headlight bulb with theheadlight

4ENG

ENGCHAPTER 4.OVERHAULING THE ENGINEENGINE ...4-

GENINFOCHAPTER 1.GENERAL INFORMATIONSCOOTER IDENTIFICATION... 1-1VEHICULE IDENTIF

ENGCRANKCASE AND REED VALVE ...4-37CRANKCASE (RIGHT) REMOVAL ...

ENG4-1OVERHAULING THE ENGINEEAS00188OVERHAULING THE ENGINEENGINELEADS AND HOSESOrder Job/Part Q’ty RemarksRemoving the leads and hoses Remove the part

ENG4-2OVERHAULING THE ENGINEOrder Job/Part Q’ty Remarks7 Starter motor lead coupler 1III Untighten :8 Rear wheel nut 1 Note:Loosen the rear wheel nu

ENG4-3OVERHAULING THE ENGINEEXHAUST PIPEOrder Job/Part Q’ty RemarksRemoving the exhaust pipe Remove the parts in the order listed.Lower cover Refer to

ENG4-4OVERHAULING THE ENGINEOrder Job/Part Q’ty RemarksRemoving the engine Remove the parts in the order listed.Leads and hoses NOTE:Exhaust pipe Plac

ENG4-5Order Job/Part Q’ty RemarksI. Install: Engine mounting bolt  1 Rear shock absorber bolt (lower)  1 NOTE:Do not fully tighten the bolts.II. Tig

ENG4-6CYLINDER HEADEAS00222CYLINDER HEAD, CYLINDER AND PISTONOrder Job/Part Q’ty RemarksRemoving the cylinder head Remove the parts in the order liste

ENG4-7PISTON PIN AND PISTON REMOVAL1. Remove:• Piston pin clip NOTE:Before removing the piston pin clip, cover thecrankcase with a clean rag so you w

ENG4-8CYLINDER AND PISTON INSPECTION1. Eliminate :• Carbon depositsUse a rounded scraper .2. Inspect :• Cylinder wallWear/Scratches→Rebore or replace

ENG4-9• If out of specification, rebore or replacecylinder, and replace piston and piston ringsas a set.2nd step:• Measure the piston skirt diameter “

GENINFO1-1112GENERAL INFORMATIONEAS00015GENERAL INFORMATIONSCOOTER IDENTIFICATIONEAS00017VEHICLE IDENTIFICATION NUMBERThe vehicle identification numb

ENG4-10 a Measuring Point 20 mmPISTON RINGS INSPECTION1. Measure:• Side clearanceOut of specification→Replace piston and/or rings.Use a feeler gauge 

ENG4-112. Measure :• Outside diameter @ (piston pin)Out of specification→Replace.Outside diameter (piston pin) :13.996~14.000 mm3. Measure:• Piston pi

ENG4-123. Install :• Small end bearing• Piston • Piston pin • Piston pin clip NOTE:• The arrow a on the piston to the exhaust side.• Before insta

ENG4-134. Install :• Cylinder head gasket (new gasket)5. Install :• Cylinder head  14Nm(1.4m.kg)• Spark plug  20Nm(2.

ENG4-14RemarksRemove the parts in order.Reverse the removal procedure for installation.Order123456Q’ty111112Job name/Part nameCrankcase cover (left) r

ENG4-15OrderQ’ty111/1111KICK STARTERJob name/Part nameKick starter removalKickstarter pinion gearKickstarter pinion gear clipCirclip/Plain washe

ENG4-16KICK STARTER INSTALLATION1. Install :• Return spring • Kick shaft • Collar • Plain washer • Circlip **************************************

ENG4-17Order12345678910Q’ty1111/1111/111/36V-BELT, CLUTCH AND SECONDARY/PRIMARY SHEAVERemarksRemove the parts in order.Refer to “BATTERY COVER ANDLOWE

ENG4-18SECONDARY SHEAVESECONDARY SHEAVE50Nm(5.0kg.m)T R..OrderQ’ty1131121221RemarksDisassemble the parts in order.Refer to “SECON

ENG4-19PRIMARY SHEAVE REMOVAL1. Remove :• Fan2. Remove :• Nut  (primary sheave)NOTE:When loosening the nut (primary sheave), holdthe C.D.I. magneto u