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It is not possible to put an entire mechanic’s education into one manual, so it is assumed that persons using this book to perform maintenance and repairs on YAMAHA and MBK scooters have a basic understanding of the mechanical concepts and procedures inherent in scooter repair technology.
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HOW TO USE THIS MANUAL CONSTRUCTION OF THIS MANUAL This manual consists of chapters for the main categories of subjects. (See «illustrated symbols). 1st title 1 This is a chapter with its symbol on the upper right of each page. 2nd title 2 This title appears on the upper of each page on the left of the chapter symbol.
ILLUSTRATED SYMBOLS (REFER TO THE ILLUSTRATION) SPEC INFO Illustrated symbols Q to W are designed as thumb tabs to indicate the chapter’s number and content. INSP Q General information W Specifications E Periodic inspection and adjustment R Engine CARB CHAS T Carburetion Y Chassis U Electrical...
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INDEX GENERAL INFORMATION INFO SPECIFICATIONS SPEC PERIODIC INSPECTION INSP AND ADJUSTMENT ENGINE OVERHAUL COOLING SYSTEM CARBURETION CARB CHASSIS CHAS ELECTRICAL ELEC TROUBLESHOOTING TRBL SHTG...
INFO CHAPTER 1. GENERAL INFORMATION SCOOTER IDENTIFICATION ................ 1-1 VEHICLE IDENTIFICATION NUMBER ............ 1-1 ENGINE SERIAL NUMBER ..............1-1 IMPORTANT INFORMATION ............... 1-2 ALL REPLACEMENT PARTS ..............1-2 GASKETS, OIL SEALS, AND O-RINGS ..........1-2 LOCK WASHERS/PLATES AND COTTER PINS ........1-2 BEARINGS AND OIL SEALS ..............
INFO SCOOTER IDENTIFICATION GENERAL INFORMATION SCOOTER IDENTIFICATION VEHICLE IDENTIFICATION NUMBER The vehicle identification number Q is stamped into the frame. NOTE: The vehicle identification number is used to identify your scooter and may be used to register your scooter with the licensing authority in your state.
ALL REPLACEMENT PARTS 1.Use only genuine parts for all replacements. Use oil and/or grease recommended by MBK/ YAMAHA for assembly and adjustment. Other brands may be similar in function and appearance, but inferior in quality. GASKETS, OIL SEALS, AND O-RINGS 1.All gaskets, seals and O-rings should be...
INFO IMPORTANT INFORMATION CIRCLIPS 1.All circlips should be inspected carefully before reassembly. Always replace piston pin clips once they have been removed. Replace bent circlips. When installing a circlip Q make sure that the sharp edge W is positioned opposite to the thrust E it receives.
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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INFO SPECIAL TOOLS Tool N° Tool name/usage Illustration 9079Q-02218 Ring nut wrench. This tool is used to loosen and tighten the steering ring nut. 90890-01326 T-handle Damper rod holder 90890-1294 These tools are used for holding the damper rod holder when removing or in- stalling the damper rod holder.
Compression ratio 7.9 : 1 (F)(B)(P)(E)(I) 8 : 1 (D)(NL)(CHE) Starting system Electric and kick starter Lubrication system: Separate lubrication (Yamaha Autolube ) Oil type or grade: Engine oil: Semi-synthetic, in accordance with the API TC TSC 3 Standard. Transmission oil...
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SPEC GENERAL SPECIFICATIONS Model YQ50 Carburetor: Type/Manufacturer PHBN12HS / DELL'ORTO Spark plug: Type/Manufacturer BR8HS/NGK 0.5 ~ 0.7 mm Clutch type: Dry, centrifugal automatic Transmission: Primary reduction system Helical gear Primary reduction ratio 52/13 (4.000) Secondary reduction system Spur gear Secondary reduction ratio 43/14 (3.071)
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SPEC GENERAL SPECIFICATIONS Model YQ50 Electrical: Ignition system Charging system Flywheel magneto Battery type/model GM4-3B, YB4L-B, FB4L-B Battery capacity 12V 4AH Headlight type: Bulb Bulb wattage / quantity: Headlight 12V 35W/35W x 1 Auxiliary light 12V 5W x 1 Taillight/brake light...
SPEC CABLE ROUTING A Push the end grip againt the handlebar and tighten to 0.6 ~ 0.8 m.kg. CABLE ROUTING B Tighten the front screw first. Q Handlebar end grip C Apply the left switch handle against the handlebar. W Right handlebar switch D Hole for the front flasher harness.
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SPEC CABLE ROUTING A Insert the fuel sender completly. CABLE ROUTING B Turn the fuel sender so that the cable points toward. Q Fuel sender C Pass the fuel lines above the rear brake hose. W Fuel tank D Pass the fuel overflow pipe in the trunk slot. E Fuel overflow pipe E Push the fuel cock (without turning it) completly in the tank and screw R Fuel cock...
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SPEC CABLE ROUTING A Set the seat lock adjuster so that there is a gap betwween 8 ~ 9 mm Q Seat lock W Starter motor at the seat lock aperture. B Install the starter relay on the footrest board. E Ignition coil C Group the connections here.
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SPEC CABLE ROUTING Q Wiring harness A Install the wiring harness in the middle of the frame. W Resistor B Set the resistor at 45°0/+30’ on the frame bracket. E Horn C Clip the front brake hose on the front fork bracket. R Front brake hose D Install the 8 clamps just beside the marks at the end side of the hoses.
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SPEC CABLE ROUTING Q Rear brake hose A Install the rear brake hose in the clip. W Seat lock cable B Install the oil delivery hose (from oil pump to carburator) under the E Wire harness water hose. R Throttle cable C Pass the rear brake hose under the frame reinforcement tube.
• Correct if necessary. Items marked with an asterisk ( * ) require special tools, data and technical skills for servicing. Take the scooter to a Yamaha or MBK Dealer when servicing these items. ** : Medium weight wheel bearing grease.
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INSP PERIODIC MAINTENANCE/LUBRICATION INTERVALS NOTE: Brake fluid replacement: 1.When disassembling the master cylinder or caliper cylinder, replace the brake fluid. Normally check the brake fluid level and add fluid as required. 2.On the inner parts of the master cylinder and caliper cylinder, replace the oil seals every two years. 3.Replace the brake hoses every four years, or when cracked or damaged.
INSP COVERS REMOVAL 8 Nm (0,8 m.kg) 3 Nm (0,3 m.kg) 8 Nm (0,8 m.kg) 2 Nm (0,2 m.kg) Name of the intervention/ Mark Observation of the part Seat Fuel tank cap Rear seat screws and strap Side cover (left and right) Rear seat CAUTION: When removing the cover, be careful...
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INSP COVERS REMOVAL 8 Nm (0,8 m.kg) 3 Nm (0,3 m.kg) 2,5 Nm (0,25 m.kg) 6 Nm (0,6 m.kg) Name of the intervention/ Mark Observation of the part Glove compartment cover Oil cover Side cover (left and right) Rear mudguard CAUTION: When removing the cover, be careful not to damage the mounting clips.
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INSP COVERS REMOVAL 13 Nm (1,3 m.kg) 6,5 Nm (0,65 m.kg) 3 Nm (0,3 m.kg) 6,5 Nm (0,65 m.kg) 2 Nm (0,2 m.kg) Name of the intervention/ Mark Observation of the part Frame reinforcement Fuel tank Rear lower cover Rear light CAUTION: When removing the cover, be careful not to damage the mounting clips.
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INSP COVERS REMOVAL 3 Nm (0,3 m.kg) 3 Nm (0,3 m.kg) 2 Nm (0,2 m.kg) 3 Nm (0,3 m.kg) 3 Nm (0,3 m.kg) Name of the intervention/ Mark Observation of the part Front cover and headlight Front inner cover Front fender Front inner panel CAUTION: When removing the cover, be careful...
INSP COVERS HANDLEBAR COVERS 3 Nm (0,3 m.kg) 3 Nm (0,3m.kg) 3 Nm (0,3 m.kg) Name of the intervention/ Mark Observation of the part Handlebar cover (front) Handlebar cover (rear) Meter Flasher light CAUTION: When removing the cover, be careful not to damage the mounting clips.
INSP COVERS REMOVAL 3 Nm (0,3 m.kg) 3 Nm (0,3 m.kg) Name of the intervention/ Mark Observation of the part Battery cover Lower cover CAUTION: When removing the cover, be careful not to damage the mounting clips. For installation,reverse the “REMOVAL”...
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INSP COVERS REMOVAL 4 Nm (0,4 m.kg) 4 Nm (0,4 m.kg) Name of the intervention/ Mark Observation of the part Inner panel Main switch ring. Turn the ring anticlockwise to remove it Footrest board CAUTION: When removing the cover, be careful not to damage the mounting clips.
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INSP COVERS NOTE: Correct routing of cables and wires is essential for a safe operation of this scooter. Refer to the section “CABLE ROUTING” in Chapter 2. NOTE: Be careful not to pinch any wires with the covers. NOTE: When installing the covers, be careful not to damage the mounting clips. 3-10...
INSP ENGINE IDLE SPEED ADJUSTMENT ENGINE ENGINE IDLE SPEED ADJUSTMENT 1. Tighten : • Pilot air screw Turn the pilot air screw in until lightly seated. 2. Loosen : • Pilot air screw Back out from the lightly seated position. Pilot air screw position : DELL'ORTO ±...
INSP AUTOLUBE PUMP AIR BLEEDING AUTOLUBE PUMP AIR BLEEDING 1. Bleed : • Pump housing and oil hose ******************************************************* Pump bleeding steps : Place a rag under the pump. Remove the bleed screw . Let oil run until there are no more air bubbles in it.
INSP COOLANT LEVEL INSPECTION/ COOLANT REPLACEMENT COOLANT LEVEL INSPECTION NOTE: Install the scooter straight up when inspecting the coolant level. 1.Place the scooter on a level surface. NOTE: Place the scooter on its centerstand. 2.Remove: • Front cover Refer to the section "COVER" 3.Inspect: •...
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INSP COOLANT REPLACEMENT toward the detent. This allows any residual pressure to escape. When the hissing soound has stopped, press down on the cap while turning counterclockwise and remove it. NOTE: Position the scooter straight up when replacing the coolant. 2.Place the scooter on a level surface.
INSP AIR CLEANER ELEMENT CLEANING AIR CLEANER ELEMENT CLEANING 1. Remove : • Air cleaner case cover Q 2. Remove : • Air filter element CAUTION: Never operate the engine with the air cleaner element removed. Unfiltered air will cause rapid wear of engine parts and possible engine damage.
INSP BRAKE FLUID LEVEL INSPECTION BRAKE FLUID LEVEL INSPECTION NOTE: Position the scooter straight up when inspecting the fluid level, and make sure be turning the handlebar that the top of the master cylinder is horizontal. 1. Inspect : • Brake fluid level Brake fluid level is under “LOWER”...
INSP AIR BLEEDING (HYDRAULIC BRAKE SYSTEM)/ STEERING HEAD ADJUSTEMENT AIR BLEEDING (HYDRAULIC BRAKE SYSTEM) 1. Bleed : • Brake fluid. ******************************************************* Air bleeding steps : a. Add proper brake fluid into the reservoir. b. Install the diaphragm. Be careful not to spill any fluid or allow the reservoir to overflow.
INSP AIR BLEEDING (HYDRAULIC BRAKE SYSTEM/ STEERING HEAD ADJUSTEMENT Securing nut : 23 Nm (2.3 m.kg) NOTE : Install the torque wrench on the ring nut wrench so that it makes a 90° angle with it. Move the handlebar up and down and from front to rear.
INSP BATTERY INSPECTION/ FUSE INSPECTION CAUTION: Always charge a new battery before using it to ensure maximum performance. WARNING Battery electrolyte is dangerous. It contains sulfuric acid which is poisonous and highly caustic. Always follow these preventive measures : • Avoid bodily contact with electrolyte as it can cause severe burns and permanent eye injury.
FUSE INSPECTION/ INSP HEADLIGHT BEAM ADJUSTEMENT HEADLIGHT LENS REPLACEMENT ****************************************************** Fuse replacement steps : Turn off the ignition. Install a new fuse of the right amperage. Turn on the switches to verify the operation of the electric circuit. If the fuse immediately blows again, check the electric circuit.
ENGINE REMOVAL ENGINE REMOVAL 1. Place a suitable stand under the frame. 2. Remove : • Rear shock absorber bolt (lower) Q • Engine mounting bolt W 3. Remove : • Engine NOTE: Lift up the frame and remove the engine. 4.
ENGINE DISASSEMBLY 2. Remove : • Piston pin Q • Piston W • Piston pin bearing E CAUTION: Do not use a hammer to drive out the piston pin. 307002 KICKSTARTER 1. Remove : • Kick crank • Transmission cover Q (left) 313001 2.
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ENGINE DISASSEMBLY loosen one screw as much as required to level the tool body. 3. Remove : • Crankcase (right) As pressure is applied, keep tapping carefully on the engine mounting bosses. CAUTION: Use a soft hammer to tap on the case. Tap only on reinforced spots of the case.
INSPECTION AND REPAIR INSPECTION AND REPAIR CYLINDER HEAD 1. Eliminate : • Carbon deposits Use a rounded scraper Q NOTE: Take care to avoid damaging the spark plug threads. Do not use a sharp instrument. Avoid scratching the aluminum. 2. Inspect : •...
INSPECTION AND REPAIR If out of specification, replace piston and piston rings as a set. 3rd step : Calculate the piston-to-cylinder clearance with following formula: Piston-to cylinder clearance = Cylinder Bore “C” – Piston Skirt Diameter “P” If out of specification, replace cylinder, piston and piston rings as a set.
INSPECTION AND REPAIR Standard Limit 0.15 ~ 0.30 mm 0.70 mm ring (0.005 ~ 0.011 in) (0.028 in) 0.15 ~ 0.30 mm 0.70 mm ring (0.005 ~ 0.011 in) (0.028 in) @ Measuring Point 20 mm (0.8 in) PISTON PIN AND PISTON PIN BEARING 1.
ENGINE ASSEMBLY AND ADJUSTMENT CRANKSHAFT AND CRANKCASE Q Oil seal I Crankshaft pin W Oil seal holder O Connecting rod E Crankcase (right) P Crankshaft (left) R Dowel pin { Bearing T Bearing } Engine mount shaft Y Crankshaft (right) q Crankcase (left) U Bearing w Oil seal...
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3. Install : • Dowel pins • Spacer 313005 4. Apply : • HEATPROOF or Yamaha Bond No.1215 To the mating surfaces of both case halves. HEATPROOF or Yamaha Bond No.1215 313006 4-21...
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ENGINE ASSEMBLY AND ADJUSTMENT 5. Attach : • Crankshaft installation tool Q, W, E, R Crankshaft installation tool : Q : 90890-01274 W : 90890-01275 E : 90890-01277 R : 90890-01411 313007 NOTE: Hold the connecting rod at top dead center with one hand while tightening the nut of the installation tool with the other.
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ENGINE ASSEMBLY AND ADJUSTMENT AUTOLUBE PUMP AND CDI MAGNETO Q Nut O Gasket W Plain washer P Oil hose { Oil delivery hose E Rotor assembly R Lighting coil } Clip q Autolube pump T Charge coil Y Pick up coil w O-ring e Circlip U Stator assembly...
ENGINE ASSEMBLY AND ADJUSTMENT AUTOLUBE PUMP 1. Install : • Circlip Q • Pin W • Pump drive gear E • Circlip R 314004 2. Apply : • Lithium soap base grease (to O-ring ) 3. Install : • Autolube pump Screw (autolube pump) : 4 Nm (0.4 m.kg) 314005...
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ENGINE ASSEMBLY AND ADJUSTMENT 5. Install : • Woodruff key Q • Magneto rotor W • Plain washer E • Nut R NOTE: When installing the magneto rotor, make sure the woodruff key is properly seated in the key 321002 way of the crankshaft.
ENGINE ASSEMBLY AND ADJUSTMENT TRANSMISSION Q Circlip O Secondary sheave axle W Bearing P Bearing { Dowel pin E Oil seal R Drive axle } Gasket q Transmission case cover T Bearing Y Main axle w Circlips e Oil seal U Conical spring washer I Plain washer 10 Nm (1.0 m.kg)
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ENGINE ASSEMBLY AND ADJUSTMENT TRANSMISSION 1. Apply : • 10W30 Type SE Motor oil (to transmission case cover bearing) 2. Install : • Bearing Q 3. Install : • Oil seal W • Secondary sheave axle E NOTE: Apply lithium soap base grease onto the oil seal lips.
ENGINE ASSEMBLY AND ADJUSTMENT STARTER SYSTEM Q Collar Y Shaft W Starter wheel gear U Washer E Bearing I Idle gear R Starter clutch O O-Ring T Plate P Starter motor 8 Nm (0.8 m.kg) 13 Nm (1.3 m.kg) 4-28...
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ENGINE ASSEMBLY AND ADJUSTEMENT STARTER SYSTEM 1. Install : • Collar Q • Washer W • Bearing E • Starter wheel gear R • Starter clutch T NOTE: 317010 • Apply lithium soap base grease to the bearing. • Apply molybdenum disulfide oil to the shaft (starter clutch).
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ENGINE ASSEMBLY AND ADJUSTMENT KICK STARTER Y Washer Q Kick shaft U Circlips W Return spring I Kick crank E Collar O Kick clip R Gasket P Rachet T Transmission case 12 Nm (1.2 m.kg) 150 ~ 250 g 10 Nm (1.0 m.kg) 4-31...
ENGINE ASSEMBLY AND ADJUSTEMENT SECONDARY SHEAVE When assembling the secondary sheave, reverse the disassembly procedure. Note the following points. 1. Apply : • BEL-RAY Assembly Lube ® (to the sliding parts of the sheave) 319018 2. Install : • Sliding sheave Q NOTE: Wind adhesive tape around the end of the sheave to avoid turning over the oil seal lips when...
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ENGINE ASSEMBLY AND ADJUSTEMENT 5. Install : • V-belt Place the V-belt around the secondary sheave, and compress the secondary sheave spring hard so that the V-belt moves toward the clutch hub. NOTE: • The arrow on the V-belt must point to the front. •...
ENGINE ASSEMBLY AND ADJUSTEMENT 9. Install : • Fan Screw (fan) : 7 Nm (0.7 m.kg) KICK STARTER 1. Install : • Return spring Q • Kick shaft W • Collar E • Washer R • Circlip T 317014 2. Hook : •...
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ENGINE ASSEMBLY AND ADJUSTMENT PISTON, CYLINDER AND CYLINDER HEAD Q Carburetor joint U Cylinder gasket W Reed valve I Piston ring E Gasket O Piston R Cylinder head P Piston pin T Cylinder head gasket { Piston pin clip Y Cylinder } Bearing A Piston clearance: 0.029 ~ 0.042 mm...
ENGINE ASSEMBLY AND ADJUSTEMENT PISTON PIN AND PISTON 1. Apply : • Engine oil (to crankshaft bearing, connecting rod big end bearing, small end bearing, piston pin, piston ring grooves and piston skirt .) 2. Install : • Small end bearing •...
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ENGINE ASSEMBLY AND ADJUSTEMENT 3. Install : • Cylinder NOTE: Install the cylinder with one hand, while compressing the piston rings with the other hand. 4. Install : • Cylinder head gaskets (new gaskets) 5. Install : • Cylinder head •...
COOL COOLING SYSTEM RADIATOR Q Coolant tank cap U Impeller O-Ring W Coolant tank I Cylinder Head E Radiator O Cylinder R Hose P Thermostatic valve T Water pump { Thermo switch Y O-Ring 7 Nm (0.7 m.kg) 16 Nm (1.6 m.kg)
COOL COOLING SYSTEM COOLING SYSTEM RADIATOR REMOVAL 1.Remove: • Air filter • Carburetor assembly Refer to chepter 6 "CABURETOR" 2.Drain: • Radiator Refer to chapter 3 "COOLANT REPLACEMENT" 3.Remove: • Hose • Radiator assembly. INSPECTION 1.Inspect: • Radiator core Obstruction → Blow out with compressed air through rear of the radiator.
COOL COOLING SYSTEM WATER PUMP Q Water pump housing I Bearing W O-Ring O Rotor E Impeller P Circlips R Seal { Rubber T Cover } Driving plug Y Bearing q Washer U Spacer 7 Nm (0.7 m.kg) 6.5 Nm (0.65 m.kg) 6.5 Nm (0.65 m.kg)
CARB CARBURETOR DELL'ORTO CARBURETOR Q Carburetor top P Pilot jet W Gasket { Needle jet E Throttle valve spring } Needle valve R Needle set q Main jet T Throttle valve w Float pin Y Starter plunger spring e Float U Starter plunger r Float chamber gasket I Air screw...
CARB CARBURETOR REMOVAL 1. Remove : • Side covers and footrest board Refer to the section “SIDE COVERS AND FOOTREST BOARD” in Chapter 3. • Air filter case assembly 2.Drain: • Coolant Refer to chapter 3 "COOLANT REPLACEMENT" 3. Disconnect : •...
CARB CARBURETOR 3. Remove : • Pilot jet Q • Main jet W • Main nozzle E • Starter jet R 322027 4. Remove : • Throttle stop screw Q • Spring (throttle stop screw) • Air screw W • Spring (air screw) 322028 5.
CARB CARBURETOR ****************************************************** Float height measurement steps : • Install the needle valve, float and float pin into the carburetor body. • Hold the carburetor upside down. • Measure the height distance between the mating surface of the float chamber (gasket removed) and the top of the float, using a gauge.
CARB CARBURETOR 2. Install : • Throttle valve Q • Starter plunger NOTE: Align the groove W of the throttle valve with the projection E of the carburetor body. 322019 3. Install : • Carburetor NOTE: Align projection Q with projection W. 322020 INSTALLATION To install the carburetor reverse the “REM-...
CHAS FRONT WHEEL CHASSIS FRONT WHEEL Q Axle Y Tire W Speedometer gear U Valve E Bearing I Collar R Collar O Spacer T Front rim P Nut TIRE SIZE: 130/60 - 13 RIM RUNOUT LIMIT: VERTICAL: 1,0 mm LATERAL: 1,0 mm 35 Nm (3.5 m.kg)
CHAS FRONT WHEEL REMOVAL 1. Remove : • Front caliper fixing bolts • Front caliper • Speedometer cable Q • Axle W • Front wheel NOTE: 340003 Never depress the brake lever when the wheel is off the scooter. Otherwise the brake pads will be forced out.
CHAS FRONT WHEEL INSTALLATION Reverse the “Removal” procedure. Note the following points. 1.Lubricate : • Front wheel axle • Bearings • Oil seal (lips) • Drive/driven gear (speedometer) Recommended lubricant : Lithium soap base grease 2. Install : • Speedometer gear unit Q NOTE: Be sure that the two projections at the gear unit mesh with the two slots on the wheel hub.
CHAS FRONT BRAKE FRONT BRAKE NOTE: Q Disk U Pad spring Be sure to install the pads correctly. W Bolt I Pad retainer E Caliper O Brake pads R Piston P O-Ring T Piston seals { Bolt Y Air bleed screw } Mounting bolt A Front brake pad wear limit: 2mm B Front disk wear limit: 3.2 mm...
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CHAS FRONT BRAKE FRONT MASTER CYLINDER Q Master cylinder U Union bolt NOTE: W Master cylinder piston ass'y I Brake hose Drain completely before removing E Diaphragm O Union bolt the master cylinder. R Master cylinder cap P Front brake switch T Master cylinder bracket { Front brake lever Y Copper washer...
CHAS FRONT BRAKE WARNING • Disc brake components rarely require disassembly. Do not disassemble components unless absolutely necessary. hydraulic connection disconnected, the entire system must be disassembled, drained, cleaned, and then properly filled and bleed after reassembly. Do not use solvents on internal brake component.
CHAS FRONT BRAKE ******************************************************* Removal steps : Blow compressed air into the hose joint opening to force out the piston from the caliper body. WARNING • Never try to pry out the piston. • Cover the piston with a rag. Use care so that the piston does not cause injury as it is 346004 expelled from the cylinder.
CHAS FRONT BRAKE 4. Remove : • Master cylinder dust boot Q • Master cylinder kit W 347008 INSPECTION AND REPAIR Recommended brake component replacement schedule : Brake pads As required Piston seal, Every two years Dust seal Brake hoses Every four years Replace only...
CHAS REAR WHEEL REAR WHEEL Q Cover plug Y Valve W Nut U Rear rim E Washer I Distance collar R Bolt O Rear brake disk T Rear wheel tire TIRE SIZE: 140/60 - 13 RIM RUNOUT LIMIT: VERTICAL: 1,0 mm LATERAL: 1,0 mm 120 Nm (12.0 m.kg)
CHAS REAR WHEEL REAR MASTER CYLINDER NOTE: Q Master cylinder U Union bolt Drain completely before removing W Master cylinder piston ass'y I Brake hose the master cylinder. E Diaphragm O Union bolt R Master cylinder cap P Rear brake switch T Master cylinder bracket { Rear brake lever Y Copper washer...
CHAS REAR WHEEL WARNING • Disc brake components rarely require disassembly. disassemble components unless absolutely necessary. If any hydraulic connection is disconnected, the entire system must be disassembled, drained, cleaned, and then properly filled and bled after reassembly. Do not use solvents on internal brake component.
CHAS REAR WHEEL 3. Check : • Wheel bearings Refer to the section “FRONT WHEEL INSPECTION”. REAR BRAKE For removal, inspection and assembly refer to the section "FRONT BRAKE" INSTALLATION Reverse the REMOVAL procedure. Note the following points. 1.Install • Rear wheel 2.
CHAS FRONT FORK FRONT FORK Q Steering bracket P Spring W Bolt { Spacer E Circlip } Plunger R Rubber cap q Dust boot T Circlip w Retainer Y Spring seat e Oil seal U O-Ring r Outer fork tube I Spring t Washer O Piston...
CHAS FRONT FORK REMOVAL WARNING Securely support the scooter with a stand under the engine. 1. Place the scooter on an even surface. 2. Disconnect : • Speedometer cable 3. Remove : • Front wheel Refer to section “FRONT WHEEL” in Chapter 7. 4.
CHAS FRONT FORK DISASSEMBLY 1. Remove : • Rubber plug Q • Circlip W • Spring seat E • Spring R 342014 2. Remove : • Bolt Q • Copper washer NOTE: To remove the drain bolt Q, use the T-handle W and the holder E.
CHAS FRONT FORK 3. Install : • Copper washer • Bolt NOTE: Tighten the drain bolt Q while holding the piston with the T-handle W and holder E. T-handle for front fork : 342010 90890-01326 Holder : 90890-01294 4. Fill : •...
CHAS STEERING HEAD AND HANDLEBAR STEERING HEAD AND HANDLEBAR Q Handlebar W Nut E Bolt R Trottle grip T Throttle cable Y Starter cable (Choke) 60 Nm (6.0 m.kg) 7-22...
CHAS STEERING HEAD AND HANDLEBAR STEERING HEAD AND HANDLEBAR REMOVAL WARNING Securely support the scooter so there is no danger of it falling over. 1. Place the scooter on an even surface. 2. Remove : • Front fender • Inner panels •...
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CHAS STEERING HEAD AND HANDLEBAR CAUTION: Hold the steering shaft until it is securely attached. 4. Install : • Washer Q • Steering shaft lock nut W NOTE: 354002 Tighten the steering shaft lock nut with the ring nut wrench. Set the torque wrench to the ring nut wrench so that they form a right angle.
ELEC ELECTRICAL SYSTEM ELECTRICAL SYSTEM ELECTRICAL COMPONENTS Q Wire harness W Fuel sender E Starter relay R Ignition coil T CDI unit Y Oil sender U Battery I Resistance...
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ELEC ELECTRICAL SYSTEM ELECTRICAL COMPONENTS Q Main switch W Flasher relay E Horn R Rectifier/Regulator...
ELEC CIRCUIT DIAGRAM CIRCUIT DIAGRAM Br Gy LOCK LOCK CHECK CHECK Br Gy YB LR L r r r Br/W Br/W Dg Ch Br/W HI HI...
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ELEC CIRCUIT DIAGRAM Q Spark plug u Rear stop switch W Ignition coil i Flasher relay E CDI magneto o Flasher switch R CDI unit p Flasher indicator T Rectifier/regulator [ Rear flasher light (Left) Y Dimmer switch ] Front flasher light (Left) U Starter motor A Front flasher light (Right) I Starter relay...
ELEC IGNITION AND STARTING SYSTEM IGNITION AND STARTING SYSTEM Br Br Gy LOCK LOCK CHECK CHECK Br Gy YB LR LR L r r r Br/W Br/W Dg Ch Br/W HI HI Spark plug Fuse Ignition coil Battery CDI magneto Starter switch CDI unit Main switch...
ELEC IGNITION AND STARTING SYSTEM IGNITION AND STARTING SYSTEM CIRCUIT DIAGRAM Q Spark plug } Main switch Source coil W Ignition coil t Front brake switch Pickup coil R CDI unit y Rear brake switch Wave-shape shaping circuit U Starter Motor Condenser I Starter relay Diode...
ELEC IGNITION AND STARTING SYSTEM TROUBLESHOOTING THE STARTING SYSTEM DOES NOT WORK (NO SPARK OR IRREGULAR SPARKS). NOTE : • Remove the following parts before proceeding with the troubleshooting : 1) Side covers (left and right) • For accurate troubleshooting use the following special tools : Ignition checker : Pocket tester : 90890-06754...
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ELEC IGNITION AND STARTING SYSTEM 3.Spark plug cap resistance • Disconnect the spark plug cap. • Connect the pocket tester (Ω x 1 k) to the spark plug cap. • Check the resistance of the spark plug cap. Spark plug cap resistance : Ω...
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ELEC IGNITION AND STARTING SYSTEM TROUBLESHOOTING STARTER MOTOR DOES NOT WORK NOTE : • Remove the following parts before proceeding with the troubleshooting: 1) Side covers (left and right) 2) Footrest boards 3) Front panel 4) Handlebar cover • For accurate troubleshooting use the following special tools: Pocket tester : 90890-03112 1.Fuse...
ELEC CHARGING SYSTEM CHARGING SYSTEM WIRING DIAGRAM Br Br Gy LOCK CHECK Br Gy YB LR L r r r Br/W Br/W Dg Ch Br/W CDI magneto Rectifier/regulator Fuse Battery 8-13...
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ELEC CHARGING SYSTEM TROUBLESHOOTING THE BATTERY IS NOT CHARGED NOTE : • Remove the following parts before proceeding with the troubleshooting : 1) Side covers (left and right) and foot rest board. • For accurate troubleshooting use the following special tools : Inductive tachometer : Pocket tester : 90890-03113...
ELEC LIGHTING SYSTEM LIGHTING SYSTEM CIRCUIT DIAGRAM Br Gy LOCK CHECK Br Gy YB LR L r r r Br/W Ch Br/W Dg CDI magneto Meter light Dimmer switch Tail/Stop light Lighting switch Position light “HIGH BEAM indicator” Resistor Head light 8-16...
ELEC LIGHTING SYSTEM TROUBLESHOOTING THE AUXILIARY LIGHT, HEADLIGHT, HEADLIGHT INDICATOR, TAIL LIGHT OR METER LIGHT DO NOT WORK NOTE : Remove the following parts before proceeding with the troubleshooting : • Side covers and footrest board • Handlebar covers For accurate troubleshooting use the following special tools : Pocket tester : 90890-03112 1.
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ELEC LIGHTING SYSTEM LIGHTING SYSTEM INSPECTION 1. Headlight and headlight indicator do not work. 1. Bulb and socket NO CONTINUITY • Check the bulb and socket for continuity. Replace bulb or socket. CONTINUITY 2. Voltage • Connect the pocket tester (AC20V) to the headlight coupler.
ELEC SIGNAL SYSTEM SIGNAL SYSTEM WIRING DIAGRAM Br Br Gy LOCK LOCK CHECK CHECK Br Gy YB LR LR L r r r Br/W Ch Br/W Dg HI HI Fuse Rear flasher light (Right) Battery Horn Main switch Horn switch Tail/Stop light Oil lever indicator Flasher relay...
ELEC SIGNAL SYSTEM TROUBLESHOOTING FLASHER LIGHTS, TAIL/BRAKE LIGHT, “OIL” WARNING LIGHT DOES NOT WORK HORN DOES NOT SOUND, FUEL METER DOES NOT WORK NOTE : Remove the following parts before proceeding with the troubleshooting: • Side covers and footrest board •...
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ELEC SIGNAL SYSTEM 4. Connections POOR CONNECTIONS • Check all connections in the signal system. Refer to “WIRING DIAGRAM”. GOOD Repair. CONNECTIONS Check the condition of each circuit of the signal system. Refer to the section “SIGNAL SYSTEM CHECK”. SIGNAL SYSTEM CHECK 1.
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ELEC SIGNAL SYSTEM 2. The tail light does not work. 1. Bulb and socket NO CONTINUITY • Check the bulb and socket for continuity. CONTINUITY Replace bulb or socket. 2. Brake switch • Disconnect the brake switch leads from the wire harness.
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ELEC SIGNAL SYSTEM 3. Flasher does not work NO CONTINUITY 1. Bulb and socket • Check the bulb and socket for continuity. Replace bulb or socket. CONTINUITY 2. “TURN” switch • Disconnect the handlebar switch (left) from the wire harness. •...
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ELEC SIGNAL SYSTEM This circuit is in good condition. 4. The “OIL” indicator light does not work. 1. Bulb and socket NO CONTINUITY • Check the bulb and socket for continuity. CONTINUITY Replace bulb or socket. 2. Oil level switch •...
ELEC COOLING SYSTEM COOLING SYSTEM WIRING DIAGRAM Br Br Gy LOCK LOCK CHECK CHECK Br Gy YB LR LR L r r r Br/W Ch Br/W Br/W Dg HI HI Fuse Battery Main switch Water temperature indicator Water sender 8-30...
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ELEC COOLING SYSTEM TROUBLESHOOTING WATER TEMPERATURE METER DOES NOT MOVE, WHEN THE ENGINE IS WARM. NOTE : Remove the following parts before proceeding with the troubleshooting: • Side covers and footrest board • Handlebar cover For accurate troubleshooting use the following special tools : Pocket tester : 90890-03112 1.
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ELEC COOLING SYSTEM 4. Thermo unit • Remove the thermo unit from the head cylinder. • Connect the pocket tester (Ω x100) then (Ω x 10) to the thermo unit • Immerse the thermo unit in the water. • Measure the resistance. Thermo unit resistance: °...
TRBL SHTG STARTING FAILURE/HARD STARTING 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. STARTING FAILURE/HARD STARTING FUEL SYSTEM Fuel tank...
TRBL POOR MEDIUM AND HIGH SPEED PERFORMANCE/ FAULTY AUTOMATIC SHTG POOR MEDIUM AND HIGH SPEED PERFORMANCE FUEL SYSTEM Fuel tank Carburetor • Clogged fuel filter • Deteriorated fuel, fuel containing water or • Deteriorated fuel or fuel containing water or foreign material foreign material •...
FRONT FORK OIL LEAKAGE AND FRONT FORK TRBL MALFUNCTION/ SHTG INSTABLE HANDLING FRONT FORK OIL LEAKAGE AND FRONT FORK MALFUNCTION OIL LEAKAGE MALFUNCTION • Bent, damaged or rusty inner tube • Bent, deformed or damaged inner tube • Damaged or cracked outer tube •...
TRBL SHTG FAULTY SIGNAL AND LIGHTING SYSTEM FAULTY SIGNAL AND LIGHTING SYSTEM Headlight dark Flasher does not light • Improper bulb • Improperly grounded • Too many electric accessories • Discharged battery • Hard charging (broken charging coil) • Faulty flasher switch •...
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Q Handlebar switch (right) YQ50 WIRING DIAGRAM W ”START“ switch E ”LIGHT“ switch Meter with tachometer R Resistor T Main switch Y Ignition coil YB LR L LOCK U Spark plug LW B CHECK I Rectifier / regulator - - - -...
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