YN50 2002 5RN-AE1 SERVICE MANUAL
YN50 SERVICE MANUAL © 2002 Yamaha Motor España, S.A. First Edition, September 2002 All rights reserved. The reprinting or use of this material without the written authorisation of Yamaha Motor España, S.A is forbidden. Printed in Spain.
WARNING This Manual was written by Yamaha Motor España, S.A. principally for the use of Yamaha/MBK agents and qualified mechanics. As it is not possible to give full mechanical instructions in a manual, it is presumed that the persons using the book to carry out the maintenance and repair of Yamaha/MBK motorcycles have a basic knowledge of the concepts and procedures inherent in the technology of motorcycle repair.
HOW TO USE THIS MANUAL FORMAT OF THIS MANUAL This manual is composed of chapters on the main subject categories (See “Illustrated Symbols”). First heading : This is a chapter with a symbol at the top right-hand side of each page. Second heading : This title appears at the top of each page to the left of the chapter symbol. (For the “Inspection and periodic adjustments” chapter the third heading appears) Third heading : This is a final heading.
ILLUSTRATED SYMBOLS GEN INFO (See illustration) Illustrated symbols to are designed as tabs to be followed with the thumb to indicate the chapter number and the index.
INDEX GENERAL INFORMATION GEN/ INFO 1 SPEC 2 PERIODIC INSPECTION AND ADJUSTMENTS INSP ADJ 3 GENERAL OVERHAUL OF ENGINE ENG 4 CARB 5 CHAS 6 ELEC 7 TRBL SHTG 8 SPECIFICATIONS CARBURATION CHASSIS ELECTRICAL SYSTEM TROUBLESHOOTING
GEN/ INFO 1
GEN/ INFO CHAPTER 1 GENERAL INFORMATION IDENTIFICATION OF THE SCOOTER…………………………………………1-1 SERIAL NUMBER OF THE FRAME …………………………………………1-1 ENGINE SERIAL NUMBER……………………………………………………1-1 IMPORTANT INFORMATION …………………………………………………1-2 CHANGE OF ALL PARTS ……………………………………………………1-2 OIL SEALS AND O-RINGS ……………………………………………………1-2 SEALING WASHERS/PLATE AND KEYS……………………………………1-2 BEARING AND OIL SEALS …………………………………………………1-2 CIRCLIPS ………………………………………………………………………1-3 SPECIAL TOOLS …………………………………………………………………1-3 FOR SERVICING THE E
IDENTIFICATION OF THE SCOOTER GEN/ INFO GENERAL INFORMATION SCOOTER IDENTIFICATION FRAME SERIAL NUMBER The serial number of the frame is stamped on the steering head pipe. Frame VTL5AD according standard EU0 Frame VTLSA15 according standard EU1 Frame VTLSA19 according Mofa Version ENGINE SERIAL NUMBER The engine serial number is stamped on the upper part of the rear left-hand section of the gear box.
IMPORTANT INFORMATION GEN/ INFO IMPORTANT INFORMATION CHANGE OF ALL PARTS 1. We recommend that original Yamaha parts are used as spare parts. Use the oil and/or grease recommended by Yamaha for assembly and adjustment. GASKETS, OIL SEALS AND O-RINGS 1. All gaskets and o-rings should be replaced when the engine is overhauled and repaired. All gasket surfaces, the lips of seals and orings should be cleaned. 2. Lubricate with grease all corresponding parts and bearings during assembly.
IMPORTANT INFORMATION / SPECIAL TOOLS GEN/ INFO CIRCLIPS 1. All circlips should be carefully inspected before assembly. Always replace circlips of the piston drum after use. Replace deformed circlips. When installing a circlip , ensure that the corner with the sharp edge is placed in the opposing direction to the thrust it receives. See sectional view. Axle SPECIAL TOOLS Appropriate special tools are needed to complete and perfect assembly with accuracy.
SPECIAL TOOLS GEN/ INFO 4. Pulley wheel clamp (90890-01701) 5. Clutch spring compressor (90890-01337) 6. Crankshaft installer crucible... (90890-01274) 7. Crankshaft installer bolt...
SPECIAL TOOLS GEN/ INFO 8. Adaptor (M10)... (90890-01277) 9. Spacer... (90890-01411) FOR SERVICING THE CHASSIS 1. T-shaped handle 2... (90890-01326) Shock absorber rod support... (90890-01294-A) 2. Counterbalance for insertion of fork seals (90890-01184) 3.
SPECIAL TOOLS GEN/ INFO 4. Steering nuts wrench (90890-01403) FOR ELECTRICAL COMPONENTS 1. Pocket tester (90890-03112) 2.
SPEC 2
SPEC CHAPTER 2 SPECIFICATIONS GENERAL SPECIFICATIONS …………………………………………………2-1 MAINTENANCE SPECIFICATIONS ……………………………………………2-3 ENGINE …………………………………………………………………………2-3 CHASSIS ………………………………………………………………………2-5 ELECTRICAL SYSTEM ………………………………………………………2-6 CABLE ROUTING ……………………………………………………………2-7
GENERAL SPECIFICATIONS Model SPEC YN50R Engine: Engine type Arrangement of cylinders Cylinder capacity Diameter and stroke Compression ratio Starter system Reed valve, petrol, 2-stroke, air-cooled One cylinder inclined to the front 49.2 cc 40.0 x 39.2 mm 11.6:1 5AD 10.
GENERAL SPECIFICATIONS Model SPEC YN50R Brakes: Front brake type Operation Rear brake type Operation Disc brake Right-hand operation Drum brake Left-hand operation Suspension: Front suspension Rear suspension Telescopic fork Balancing unit Shock absorber: Front shock absorber Rear shock absorber Spring/oil shock absorber Spring/oil shock absorber Travel of wheels: Travel of front wheel Travel of rear wheel 70 mm 60 mm Electrical system: Ignition system Generating system Battery type or model Batt
MAINTENANCE SPECIFICATIONS SPEC MAINTENANCE SPECIFICATIONS ENGINE Model YN50R Cylinder head: Warping limit 0.02 mm * The lines indicate the measurement Cylinder: Internal diameter Taper limit Eccentricity limit 39.993 ~ 40.012 mm <40.1 mm> 0.05 mm 0.01 mm Piston: Piston size Measurement point Piston clearance First clearance 39.952 ~ 39.972 mm 5 mm 0.034 ~ 0.047 mm 40.50 mm Piston ring: Cross section BxT Distance between ends (installed) Lateral clearance 1.5 x 1.8 mm 0.15 ~ 0.
MAINTENANCE SPECIFICATIONS Model SPEC YN50R Automatic centrifugal clutch: Thickness of clutch shoe Free length of clutch shoe spring Clutch revolutions Clutch binding revolutions 3.600±250 rpm 5.600±400 rpm Transmission: Main axle deflection limit Drive axle deflection limit 0.08 mm 0.08 mm Choke handle: Type Pedal friction force Ratchet type 150 ~ 250 g 2 mm <1 mm> 29.
MAINTENANCE SPECIFICATIONS SPEC CHASSIS Model YN50R Steering system: Steering bearing type Front suspension: Travel of front shock absorber Free length of shock absorber spring Spring/stroke ratio Oil capacity Oil grade Rear suspension: Shock absorber travel Length of spring coupling Spring/stroke ratio Ball bearing 70 mm 226 mm (K1) (K2) 1.12 Kgf/mm 1.78 Kgf/mm 45 cm3±1 10 W shock absorber oil or equivalent 60 mm 221 mm 3.
MAINTENANCE SPECIFICATIONS SPEC ELECTRICAL SYSTEM Model YN50R Ignition system: Type Ignition distribution (A.P.M.S.) DC-C.D.I. 14*/5.000 r/min C.D.I.: Harnessing coil resistance (colour) 400 ~ 600 Ω a 20 oC (68 oF) (Black/Red-Black) Ignition coil: Spark plug electrodes gap Primary coil resistance Secondary coil resistance 6.0 mm 0.56 ~ 0.84 Ω at 20 °C 5,68 ~ 8,52 KΩ at 20 °C Charging system: Charging output 0.4 A or more/3.000 rpm/min 1 A or less/8.000 rpm/min 4.8 ~ 7.
CABLE ROUTING SPEC CABLE ROUTING A Insert the seat closing cable through the Front brake pipe Rear brake cable Rear brake calliper Rear mudguard Rear warning light Vacuum tube Fuel pipe Speedometer cable Installation 10 Breather 11 Accelerator cable 12 Seat closing cable 13 Oil hose 14 choke wire frame orifice B Connect the oil tube to the carburettor C Splice the fuel pipe to the cock D Splice the fuel pipe to the carburettor E Press the earth cable and the starter
CABLE ROUTING SPEC A Splice the electrical installation to the frame B Splice the oil pipe to the tank C Connect the oil pipe to the pump D Splice the installation to the frame E Tighten the earth cable and the ignition coil Rectifier/Regulator Main switch Fuel level measurer Horn Ignition coil Spark plug cable Oil level sensor Oil tank C.D.I.
CABLE ROUTING A Do not pinch the accelerator cable when Front break switch SPEC assembling the handlebar covers Electrical installation Intermittent relay Speedometer assembly Accelerator cable Rear brake cable Choke cable Front brake hose B Accelerator cable tensioner.
INSP ADJ 3
INSP ADJ CHAPTER 3 PERIODIC INSPECTION AND ADJUSTMENTS INTRODUCTION/PERIODIC MAINTENANCE/LUBRICATION INTERVALS …3-1 REAR BODYWORK AND FOOTREST ………………………………………3-2 REMOVAL ………………………………………………………………………3-2 INSTALLATION …………………………………………………………………3-3 MUDGUARDS, LOWER COVER AND FRONT PANEL ……………………3-4 REMOVAL ………………………………………………………………………3-5 INSTALLATION …………………………………………………………………3-5 HANDLEBAR COVERS …………………………………………………………3-5 REMOVAL ………………………………………………………………………3-5 INSTALLATION …………………………………………………………………3-5 ENGINE ……
INTRODUCTION / PERIODIC MAINTENANCE / LUBRICATION INTERVALS INSP ADJ PERIOD INSPECTION AND ADJUSTMENTS INTRODUCTION This chapter includes all information necessary to carry out inspections and adjustments recommended. These preventive maintenance procedures, if they are correctly followed, will ensure the most reliable operation of the vehicle and a longer useful life. The need for overhauls and costly repairs will be greatly reduced.
REAR BODYWORK AND FOOTREST INSP ADJ REAR BODYWORK AND FOOTREST REMOVAL 1. Raise the seat 2. Remove: • Seat 3. Remove: • Battery cover 4. Remove: • Rear cover 5. Remove: • Side covers NOTE: When the side covers are being removed unhook them from the catches and slide them outwards.
REAR BODYWORK AND FOOTREST INSP ADJ 6. Remove: • Footrest INSTALLATION When the foot support panel and the rear cover are being installed, reverse the removal process. Remember the following points. 1. Install: • Side covers NOTE: • Match up the support and hole and then apply pressure.
REAR BODYWORK, MUDGUARDS INSP ADJ REAR BODYWORK, MUDGUARDS REMOVAL 1. Remove: • Main switch cover. Turn the cover to the left and pull upwards. 2. Remove: • Upper screws in ignition key panel • Rear fairing assembly and headlight NOTE: Disconnect the headlight cable and indicators. 3. Remove: • Front lower fairing screws • Carrier hook bolt • Footrest lower cover screws 4.
HANDLEBAR COVERS INSP ADJ HANDLEBAR COVERS REMOVAL 1. Remove: • Front handlebar cover • Rear handlebar cover INSTALLATION Reverse the removal procedure. Remember the following points. 1. Install: • Front handlebar cover • Rear handlebar cover NOTE: When installing the rear cover, check that the speedometer cables goes through its housing. NOTE: After installing the handlebar cover, ensure that all the hooks are properly coupled.
ADJUSTMENT OF ENGINE IDLING INSP ADJ ENGINE ADJUSTMENT OF ENGINE IDLING 1. Tighten: • Pilot air screw Turn the pilot air screw inwards until it seats itself lightly. 2. Loosen: • Pilot air screw. Unscrew it from its lightly seated position. OUTWARDS TURNS OF THE PILOT AIR SCREW: DELLORTO GURTNER EU0 EU1 EU0 EU1 MOFA 1 1/2±14 2 1/8±1/8 1 1/8 1 7/8 1 7/8 3. Start the engine and let it warm up. s WARNING Before starting the engine, ensure that the central safety stand is being used. 4.
AJUSTE DEL JUEGO LIBRE DEL CABLE DEL ACELERADOR INSP ADJ ADJUSTMENT OF FREE PLAY OF THROTTLE CABLE 1. Check: • Free play of throttle cable a Outside specified value Adjust. Free play 2 ~ 5 mm Steps for adjusting the free play of the throttle cable: NOTE: Before adjusting the free play of the throttle, engine idling should be adjusted. First step: • Loosen the lock nut of the throttle cable.
SPARK PLUG INSPECTION INSP ADJ SPARK PLUG INSPECTION 1. Inspect: • Incorrect type of spark plug Replace Standard spark plug (5AD y SA15) BR8HS/N.G.K. for SA19 BRP4HS/N.G.K. 2. Inspect: • Electrode Worn/Damaged Replace • Insulator Abnormal colour Replace The normal colour is a light to medium coffee colour. 3. Clean the spark plug with a spark plug cleaner or wire brush. 4. Measure: • Distance between electrodes Use a thickness gauge.
INSPECTION OF ENGINE OIL LEVEL INSP ADJ INSPECTION OF ENGINE OIL LEVEL 1. Inspect: • Engine oil level Low oil level Add sufficient oil. Oil indicator light “OIL CAUTION” Visual inspection steps for engine oil level Place main switch in position (h) The “OIL CAUTION” indicator light is not lit. The “OIL CAUTION” indicator light is lit. Place the main switch in position “f” Inspect for defective electric circuit, bulbs, etc. The “OIL CAUTION” indicator light is not lit.
CHANGE OF TRANSMISSION OIL / CLEANING AIR FILTER INSP ADJ CHANGE OF TRANSMISSION OIL 1. Remove: • Drainage bolt Drain the transmission oil. • Oil refill cap 2. Inspect: • Gasket (drainage screw) • O-ring (refill cap) Damaged Change 3. Install: • Gasket • Drainage screw 2 4 Drainage screw 18 Nm (1.8 m • kg) 4. Fill: • Transmission Case Transmission oil SE engine oil type SAE 30 or GL gear oil Caacity: 0.11 L CLEANING AIR FILTER Carburettor side 1.
INSP ADJ CLEANING AIR FILTER 2. Remove: • Air filter box • Air filter ATTENTION: Never start up the engine with the air filter removed. This will allow the entry of unfiltered air, causing rapid wear and possible damage to the engine. Also, using the engine without the filter will affect the carburettor jets resulting in poor performance and the possible overheating of the engine. Be careful not to block the inlet area of the air filter with cloths or rags. 3. Inspect: • Damaged element 4.
ADJUSTMENT OF FREE PLAY OF FRONT BRAKE LEVER / ADJUSTMENT OF FREE PLAY OF REAR BRAKE LEVER / INSPECTION OF BRAKE PADS INSP ADJ CHASSIS ADJUSTMENT OF FREE PLAY OF FRONT BRAKE LEVER 1. Check: • Free play of the front brake lever. 2 ~ 5 mm s WARNING The soft or spongy feeling of the brake lever may indicate the presence of air in the brake system. This air should be extracted by bleeding the brake system before using the vehicle.
INSPECTION OF BRAKE SHOES / INSPECTION OF BRAKE FLUID LEVEL INSP ADJ NSPECTION OF BRAKE SHOES 1. Activate the brake lever 2. Inspect: • Wear indicator Indicator on wear limit line the brake shoes. Change INSPECTION OF BRAKE FLUID LEVEL NOTE: Place the scooter upright when inspecting the fluid level. 1. Inspect: • Fluid level. The fluid level is below the minimum level line Refill up to correct level. Recommended fluid: DOT 4 ATTENTION: The fluid may corrode painted surfaces or plastic parts.
AIR BLEEDING (HYDRAULIC BRAKE SYSTEM) / STEERING ADJUSTMENT INSP ADJ AIR BLEEDING (HYDRAULIC BRAKE SYSTEM) 1. Bleed: • Brake fluid Steps for air bleeding: a. Add the appropriate amount of brake fluid to the sump. b. Install the diaphragm. Take care not to spill fluid or to let the sump overflow. c. Connect the clean plastic tube . d. Place the other end of the tube in a container. e. Slowly apply the brake lever several times. f. Pull the lever inwards.
INSP ADJ INSPECTION OF TYRES Steps for tightening the steering nut: 1. Tighten the lower ring to 3.8 m • kg. 2. Loosen the lower ring nut 1/2 of a turn and tighten to 0.65 m • kg. 3. Check the steering for smooth operation. 4. Install rubber washer . 5. Install central ring nut and hand tighten untill the lower and central ring nuts slots allignet. 6. Install the lock washer . 7.
WHEEL INSPECTION / INSPECTION OF REAR FORK / REAR SHOCK ABSORBER INSPECTION INSP ADJ WHEEL INSPECTION 1. Inspect: • Wheels damaged/warped Replace. s WARNING: Never try to make even the smallest repairs on wheels. INSPECTION OF REAR FORK 1. Inspect: • Rear fork Bent/Damaged Fork bar Change Oil leaks Seals Change Rough operation Fork assembly Change REAR SHOCK ABSORBER INSPECTION 1. Inspect: • Rear shock absorber Oil leaks/Damage Replace 2.
BATTERY INSPECTION INSP ADJ ELECTRICAL SYSTEM BATTERY INSPECTION 1. Remove: • Battery cover See “REAR BODYWORK” section 2. Inspect: The fluid level between the maximum and minimum marks. Incorrect Refill ATTENTION: Add only distilled water; tap water contains minerals which are damaging to the battery. 3. Inspect: • Battery terminals Dirty terminals Clean with a wire brush Bad connection Correct NOTE: Once the terminals are clean, apply a thin cover of grease. 4.
BATTERY INSPECTION INSP ADJ Change the battery in the following cases: • When the voltage does not reach the specified value and bubbles do not appear, even after several hours of charging. • When one or more of the trays become sulphated, which can be seen when the plates become white are material accumulates on the bottom. • When the density readings after slow charging over a prolonged period, indicate that one of the trays is lower than the other.
INSPECTION OF FUSES INSP ADJ INSPECTION OF FUSES 1. Remove: • The battery cover See the “FRONT BODYWORK” section 2. Inspect: • Fuse Defective Replace Steps to be taken for blown fuses: • Disconnect the ignition and circuit. • Install a new fuse of the correct amperage. • Connect the switches to check the correct operation of the electrical device. • If the fuse blows immediately after, check the circuit concerned.
ADJUSTMENT OF HEADLAMP BEAM / REPLACEMENT OF HEADLAMP BULB INSP ADJ ADJUSTMENT OF HEADLAMP BEAM 1. Adjust: • Headlamp (vertically) To raise the beam Turn the screw inwards To lower the beam Turn the screw outwards REPLACEMENT OF HEADLAMP BULB 1. Remove: • Front fairing 2. Disconnect • Headlamp cables 3. Remove: • Headlamp bulb cover • Headlamp bulb 4.
ENG 4
ENG CHAPTER 4 GENERAL OVERHAUL OF ENGINE ENGINE REMOVAL ………………………………………………………………4-1 REAR COVER AND FOOTREST PANEL ……………………………………4-1 CARBURETTOR ………………………………………………………………4-1 SILENCER ASSEMBLY ………………………………………………………4-1 CABLES AND TUBES …………………………………………………………4-2 REMOVAL OF ENGINE ………………………………………………………4-3 DISASSEMBLY THE ENGINE …………………………………………………4-4 REAR WHEEL …………………………………………………………………4-4 CENTRAL SUPPORT …………………………………………………………4-4 CYLINDER HEAD AND CYLINDERS ………………………………………4-4 PISTON PINS AND PISTON …………………………………
ENGINE REMOVAL ENG GENERAL OVERHAUL OF THE ENGINE REMOVAL OF ENGINE REAR BODYWORK AND FOOTREST 1. Remove: • Side covers (left and right) • Rear cover • Footrest panel See section in chapter 3 “REAR BODYWORK AND FOOTREST” CARBURETTOR 1. Remove: • Air filter box assembly 1 2. Disconnect: • Autochoke wire • Trhottle cable 3. Remove: • Oil discharge tube • Fuel supply tube • Carburettor 1 SILENCER ASSEMBLY 1. Remove: • Silencer assembly • Ventilator cover 2.
ENGINE REMOVAL ENG CABLES AND PIPES 1. Remove: • Oil pipe from side of oil pump. NOTE: Position oil pipe so that the oil does not spill out. 2. Remove: • Bolts (trunk) • Overflow bowl rivets NOTE: To remove the overflow bowl, take off the fuel and oil caps and replace them immediately after removing the bowl. 3. Disconnect: • Battery cable • Starter motor cable • Magnetic flywheel cable • Spark plug pipe 4.
ENGINE REMOVAL ENG ENGINE REMOVAL 1. Remove: • Rear shock absorber screw (lower) 2. Remove: • Engine assembly screw • Engine Lift the frame and remove the engine 3.
DISASSEMBLY THE ENGINE ENG DISASSEMBLY ENGINE REAR WHEEL 1. Remove: • Rear wheel • Brake shoes • Flat washer CENTRAL STAND 1. Remove: • Clip • Rubber washer • Axle • Clasp • Spring • Central stand CYLINDER HEAD AND CYLINDER 1. Remove: • Cover • Cylinder head • Cylinder head gasket NOTE: • Before loosening the cylinder head, loosen the spark plug . • The position nuts of the cylinder head should be loosened by 1/2 a turn each time and then removed. 2.
DISASSEMBLY THE ENGINE ENG 2. Remove: • Piston pin • Piston • Piston pin bearing ATTENTION: Do not use a hammer to take out the piston pin. KICKSTART SYSTEM 1. Remove: • Kickstart pedal • Crankcase cover (left) 2. Remove: • Guide(air filter) • Air filter 3. Remove: • Pedal gear NOTE: When the pedal gear removed, move the pedal axle. 4. Unhook: • Return spring 5.
DISASSEMBLY THE ENGINE ENG PRIMARY PULLEY WHEEL 1. Remove: • Fan 2. Remove: • Nut (primary pulley wheel) NOTE: When the nut is loosened (primary pulley wheel), support the magnetic flywheel using the engine wheel support tool Engine wheel holding tool: 90890-01235 3. Remove: • Conical spring washer • One-way clutch • Washer • Fixed primary pulley wheel • Shim • Trapezoidal belt 4. Remove: • Hub • Primary pulley wheel assembly SECONDARY PULLEY WHEEL 1.
DISASSEMBLY THE ENGINE ENG 3. Apply: • Pulley wheel clamp • Nut spanner (41MM) Pulley wheel clamp: 90890-01701 4. Loosen: • Clutch positioning nut ATTENTION: Do not remove the clutch positioning nut yet. 5. Apply: • Clutch spring compressor Clutch spring compressor: 90890-01337 6. Remove: • Clutch positioning nut 7. Remove: • Clutch assembly • Clutch spring • Spring seat • Guide pins • Secondary sliding pulley wheel STARTER SYSTEM 1.
DISASSEMBLY THE ENGINE ENG TRANSMISSION 1. Remove: • Transmission box cover • Gasket • Centring devices NOTE: Before proceeding to disassemble the transmission cap, empty the oil. 2. Remove: • Main axle • Drive axle • Flat washer • Conical spring washer 3. Remove: • Oil seal • Bearing • Secondary pulley wheel axle MAGNETIC FLYWHEEL 1. Remove: • Nut (rotor) • Flat washer NOTE: Support the rotor to loosen the nut with the engine flywheel support tool .
DISASSEMBLY THE ENGINE ENG AUTOLUBRICATION PUMP 1. Remove: • Autolubrication pump 2. Remove: • Elastic circlip • Pump drive gearing • Pin • Elastic circlip 3. Remove: • Carburettor gasket • Reed valve • Reed valve gasket CRANKCASE AND CRANKSHAFT 1. Remove: • Oil seal catch • Screws (crankcase) NOTE: Loosen each screw 1/4 of a turn and remove them after loosening them. 2.
DISASSEMBLY THE ENGINE ENG 3. Remove: • Crankcase (right) While pressure is applied, strike alternatively on the engine assembly hubs. 4. Apply: • Crankcase separation tool Crankcase separation tool 90890-01135 5.
INSPECTION AND REPAIR ENG INSPECTION AND REPAIR CYLINDER HEAD 1. Eliminate: • Carbon deposits Use a rounded scraper 2. Inspect: • Cylinder head warping. Outside specified value Rectify Steps for measuring warping and rectification: • Join a straight edge and a thickness calibration on the cylinder head • Measure the limit of the warping Warping limit 0.
ENG INSPECTION AND REPAIR 4. Remove: • Cracking marks and carbon deposits on piston sides. 5. Inspect: • Piston wall Wear/striping/damage Change 6. Measure: • Cylinder piston clearance Steps for measuring the clearance of the cylinder piston First step: • Measure the lower diameter “C” with a dial gauge. NOTE: Measure the inner diameter of cylinder “C” in parallel and at right angles to the crankshaft. Then find the mean of the measurements. Standard Wear limit 40.
INSPECTION AND REPAIR ENG Size of the piston P Standard 1st Clearance 2st Clearance 39.952 ~ 39.997 mm 40.25 mm 40.50 mm • If this is outside the specified value change the piston and the set of rings. Third step: • Calculate the clearance of the piston to the cylinder using the following formula: Clearance of piston to cylinder = Inner diameter of cylinder “C” – Diameter of piston skirt “P” • If this is outside the specified value, rectify or change the cylinder and change the piston and set of rings.
INSPECTION AND REPAIR ENG 3. Measure: • Gap between ends Outside specified value Change set of rings. Use a thickness gauge . Standard Limit Top ring 0.15~0.35 mm 0.60 mm Second ring 0.15~0.35 mm 0.60 mm a Measurement point 20 mm (0.8 in) 4. Clearance of piston rings: The size of the rings is not stamped on its upper part. Piston ring clearance 1st Clearance 40.25 mm 2st Clearance 40.50 mm PISTON PIN AND PISTON PIN BEARING 1.
INSPECTION AND REPAIR ENG 4. Inspect: Bearing (piston pin) Pitting/Damage Change KICKSTART 1. Inspect: • Pedal gear teeth • Pedal pinion gear teeth Burrs/Spalling/Non-uniformity/Wear Change 2. Inspect: • Locking bolt(pedal pinion gear and one way clutch) Rounded edges/Wear Change 3.
INSPECTION AND REPAIR ENG TRANSMISSION 1. Inspect: • Drive axle • Main axle • Secondary pulley wheel axle Burrs/Spalling/Non-uniformity/Wear Change 2. Inspect: • Secondary pulley wheel axle bearing • Main axle bearing • Drive axle bearing Pivot the inner guide of the bearing. Excessive play/Non-uniformity Change Pitting/Damage Change AUTOLUBRICATION PUMP Internal wear or poor operation may cause the pump to deviate from its factory adjustment. However, this is very uncommon.
INSPECTION AND REPAIR ENG Deflection limit “C”: 0.03 mm Clearance on big end side “D”: 0.2 ~ 0.5 mm Free play at small end “F”: 0.4 ~ 0.8 mm 2. Inspect: • Bearings (crankshaft) Pivot the inner bearing guide. Excessive play/Non-uniformity Change Pitting/Damage Change PRIMARY PULLEY WHEEL 1. Inspect: • Primary sliding pulley wheel • Primary fixed pulley wheel Wear/Cracks/Striping/Damage Change 2.
INSPECTION AND REPAIR ENG SECONDARY PULLEY WHEEL 1. Inspect: • Secondary fixed pulley wheel • Secondary sliding pulley wheel Striping/Cracks/Damage Change set. • Oil seal Damage Change. 2. Inspect: • Turning cam groove • Guide pin Wear/Damage Change set. • O-ring Damaged Change. 3. Measure: • Free length of variator spring. Outside specified value Change Free length of secondary pulley wheel 109.6 mm 90.4 mm 4.
INSPECTION AND REPAIR ENG 6. Inspect: • Clutch shoes shiny parts sand paper. Polish with NOTE: After using sand paper, clean the polished particles with a cloth. 7. Measure: • Thickness of clutch shoe a Outside specified value Change Thickness of clutch shoe 2.0 mm 1.0 mm TRAPEZOIDAL BELT 1. Inspect: • Trapezoidal belt Cracks/Wear Change NOTE: Replace the trapezoidal belt if it is dirty with oil or grease. 2.
INSPECTION AND REPAIR ENG 2.
ASSEMBLY AND ADJUSTMENT OF ENGINE ASSEMBLY AND ADJUSTMENT OF ENGINE CRANKSHAFT AND CRAKCASE Oil seal Oil seal catch Crankcase (right) Centring device Bearing Crankcase (right) Bearing Crankshaft pin Connecting rod 10 Crankcase (left) 11 Bearing 12 Engine mounting spacer 13 Crankcase (left) 14 Oil seal CRANKSHAFT A: 37.90 ~ 37.95 mm C: 0.03 mm D: 0.2 ~ 0.5 mm F: 1.0 mm 0.4 ~ 0.
ASSEMBLY AND ADJUSTMENT OF ENGINE MOT CRANKSHAFT AND CRANKCASE 1. Place: • Crankshaft installation tool Crankshaft installation tool: : 90890-01411 : 90890-01274 : 90890-01275 : 90890-01277 2. Install: • Crankshaft (in left crankcase) 3. Install: • Centring device • Engine mounting spacer 4. Apply: • Yamaha N.º 1215 adhesive on the corresponding surfaces of both halves of the crankcase Yamaha N. 1215 adhesive: 90890-85505 5.
ASSEMBLY AND ADJUSTMENT OF ENGINE AUTOLUBRICATION PUMP AND MAGNETIC FLYWHEEL Fan Flat washer Rotor assembly Charge coil Lighting coil Harnessing coil Stator plate Oil seal Gasket 10 Oil outlet pipe 11 Oil pipe 12 Bushing 13 Autolubrication pump 14 O-ring 15 Elastic circlip 16 Oil pump drive gear 17 Pin 4-23 MOT
ASSEMBLY AND ADJUSTMENT OF ENGINE MOT AUTOLUBRICATION PUMP 1. Install: • Elastic circlip • Pin • Pump drive gear • Elastic circlip 2. Apply: • Grease with lithium soap base (on the o-ring ) 3. Install: • Autolubrication pump Screw (autolubrication pump) 0.4 m • kg 4. Apply: • Grease with lithium soap base (on the autolubrication pump gear , ) 15 cc FLYWHEEL MAGNETO 1. Install: • Seal 2. Apply: • Grease with lithium soap base (on the oil reten ) 3.
ASSEMBLY AND ADJUSTMENT OF ENGINE MOT TRANSMISSION Circlip Bearing Oil seal Drive axle Bearing Main axle Conical spring washer Flat washer Secondary pulley wheel axle 10 Bearing 11 Centring device 12 Seal 13 Transmission box cover 14 Bearing 15 Oil seal 4-25
ASSEMBLY AND ADJUSTMENT OF ENGINE MOT 6. Tighten: • Nut (flywheel magneto) Use the engine wheel support tool . Engine wheel support tool 90890-01235 Flywheel nut 4.3 m • kg TRANSMISSION 1. Apply: • SE engine oil type 10W30 (on the transmission box cover bearing) 2. Install: • Secondary pulley wheel axle (on transmission box cover) 3. Install: • Circlip • Oil seal NOTE: Apply grease with lithium soap based on the oil seal lips. 4. Check: • Rotation of secondary pulley wheel axle.
ASSEMBLY AND ADJUSTMENT OF ENGINE STARTER SYSTEM Bushing Bearing Starter wheel gear Starter clutch Plate Axle Flat washer Intermediate gear O-ring 10 Starter engine 4-27 MOT
ASSEMBLY AND ADJUSTMENT OF ENGINE MOT STARTER SYSTEM 1. Install: • Bushing • Bearing • Starter wheel gear • Starter clutch NOTE: • Apply grease with a lithium soap base on the bearing . • Apply molybdenum disulphide oil on the pin (starter clutch) . 2. Install: • Flat washer • Intermediate gear • Flat washer • Plate (intermediate gear) Screw (intermediate gear plate) 0,8 m • kg NOTE: Apply engine oil on the intermediate gear . 3.
ASSEMBLY AND ADJUSTMENT OF ENGINE MOT SECONDARY AND PRIMARY PULLEY WHEEL Nut Clutch drum Clutch plate Shoe spring Clutch spring Spring seat Oil seal O-ring Secondary sliding pulley wheel 10 Trapezoidal belt 11 Guide pin 12 Secondary fixed pulley wheel 13 Conical washer 14 One-way clutch 15 Washer 16 Fixed primary pulley wheel FREE LENGTH LIMIT OF VARIATOR: 83 mm WASTE LIMIT OF CLUTCH HOUSING: 107.4 mm WASTE LIMIT OF CLUTCH SHOES: 1.0 mm TRAPEZOIDAL BELT WASTE LIMIT: 15.
ASSEMBLY AND ADJUSTMENT OF ENGINE KICKSTART PEDAL Pedal axle Return spring Bushing Flat washer Elastic retainer Starter pedal Spring Pedal pinion gear 10 Nm (1.
ASSEMBLY AND ADJUSTMENT OF ENGINE MOT SECONDARY PULLEY WHEEL When assembling the secondary pulley wheel, reverse the disassembly procedure. Remember the following points: 1. Apply: • Assembly grease (in the sliding/fixed pulley wheel) 2. Install: • Sliding pulley wheel NOTE: Take care that the lips of the oil seals do not turn when the pulley wheel is installed. 3. Apply: • Assembly grease (on the torsion cam grooves and o-rings) 4. Check: • Sliding pulley wheel. Faulty operation Repair. 5.
ASSEMBLY AND ADJUSTMENT OF ENGINE MOT 7. Install: • Conical pin • Crankcase cover seal • Secondary pulley wheel assembly • Clutch drum 8. Tighten: • Nut (secondary pulley wheel) Use the pulley wheel support Pulley wheel clamp 90890-01701 Clutch drum nut 4.0 m • kg 9. Install • O-ring PRIMARY PULLEY WHEEL 1. Clean: • Surface of primary sliding pulley wheel • Surface of primary fixed pulley wheel • Hubs • Rollers • Roller races 2.
ASSEMBLY AND ADJUSTMENT OF ENGINE MOT 6. Install: • Shim • Primary fixed pulley wheel • Washer • One-way clutch • Conical spring washer • Nut 7. Tighten: • Nut (primary pulley wheel) Primary pulley wheel nut 3,3 m • kg NOTE: When the nut is tightened (primary pulley wheel), support the magnetic flywheel using the engine wheel support tool Engine wheel support tool 90890-01235 8. Adjust: • Trapezoidal belt Tense the trapezoidal belt by turning the primary pulley wheel several times 9.
ASSEMBLY AND ADJUSTMENT OF ENGINE MOT 2. Hook on: • Return spring (on pedal gear and hub) 3. Install: • Pedal pinion gear 4. Install: • Crankcase cover Screw (crankcase cover) 7 Nm (0.7 m • kg) 5. Install: • Kickstart pedal Kickstart pedal 0.
ASSEMBLY AND ADJUSTMENT OF ENGINE MOT PISTON, CYLINDER AND CYLINDER HEAD Carburettor gasket Reed valve Gasket Cylinder head Cylinder head gasket Cylinder Cylinder seal Piston rings Piston 10 Piston pin 11 Circlips 12 Bearing SPARK PLUG MANUFACTURER/TYPE: NKG/BR7HS GAP BETWEEN ELECTRODES 0.06 ~ 0.7 mm CLEARANCE FROM PISTON TO CYLINDER: 0.034 ~ 0.047 mm Limit: 0.1 mm BETWEEN ENDS (INSTALLED): Top ring 0.15 ~ 0.35 mm Limit: 0.60 mm Second ring 0.15 ~ 0.35 mm Limit: 0.
ASSEMBLY AND ADJUSTMENT OF ENGINE MOT PISTON AND PISTON PIN 1. Apply: • Engine oil (in the crankshaft bearing, big end bearing, small end bearing, piston pin, piston ring grooves and piston skirt areas.) 2. Install: • Reed valve gasket • Reed valve • Carburettor gasket Carburettor gasket 0.9 m • kg 3. Install: • Small end bearing • Piston • Piston pin • Piston circlips NOTE: • The arrow of the piston should point to the exhaust side.
ASSEMBLY AND ADJUSTMENT OF ENGINE MOT 3. Install: • Cylinder NOTE: Install the cylinder with one hand while compressing the piston rings with the other. 4. Install: • Cylinder head gasket (new gasket) 5. Install: • Cylinder head • Spark plug • Air protector NOTE: • The arrow “EX” from the cylinder head should point to the exhaust side. • Tighten the cylinder head positioning nuts in several steps, using a cris-cross pattern Cylinder head positioning screws 1.4 m • kg spark plug 2.0 m • kg 6.
ASSEMBLY AND ADJUSTMENT OF ENGINE ASSEMBLY OF ENGINE When the engine is being assembled, reverse the removal procedure 1. Install: • Engine assembly bolt • Rear shock absorber bolt (lower) MOT Engine assembly bolt 8.4 m • kg Rear shock absorber bolt (lower) 1.8 m • kg 2. Install: • Carburettor • Oil supply pipe • Fuel pipes • Air filter box assembly NOTE: • Align the projection of the carburettor with the projections of the head • Before installing the oil supply pipe, fill it with oil. 3.
ASSEMBLY AND ADJUSTMENT OF ENGINE MOT 6. Install: • Silencer • Fan cover 2 Bolt (silencer) 2.6 m • kg Bolt (exhaust pipe) 0.9 m • kg 1 7. Apply: • Transmission oil. See chapter 3 section - “CHANGING TRANSMISSION OIL”. 8. Adjust: • Free play of brake levers. See chapter 3, section – “ADJUSTMENT OF FREE PLAY OF FRONT/REAR BRAKE LEVER”. • Free play of accelerator cable See section “ADJUSTMENT OF FREE PLAY OF ACCELERATOR CABLE”. 9.
CARB 5
CARB CHAPTER 5 CARBURETOR CARBURETOR ……………………………………………………………………5-1 REMOVING THE CARBURETOR ……………………………………………5-2 DISASSEMBLING THE CARBURETOR ……………………………………5-2 CHECKING THE CARBURETOR ……………………………………………5-3 ASSEMBLING THE CARBURETOR …………………………………………5-5 CHECKING THE AUTOCHOKE UNIT ………………………………………5-6 INSTALLING THE CARBURETOR……………………………………………5-7 FUEL COCK ………………………………………………………………………5-7 CHECKING THE FUEL COCK ………………………………………………5-7 REED VALVE ………………………………………………………………………5-8 REMOVING THE REED VALVE ………………………………………
CARBURETOR CARB EAS00480 CARBURETOR CARBURETOR Pilot jet Throttle valve spring Spring catch Throttle valve Jet needle Pilot air screw Throttle stop screw Needle jet Main jet 10 Float 11 Float gasket 12 Drain screw 13 Needle valve 14 Float chamber 15 Autochoke unit carburetor dell’orto 15 carburetor gurtner 15 13 13 10 10 11 11 14 14 12 5-1
CARBURETOR REMOVING THE CARBURETOR 1. Remove: • air filter box • helmet box Refer to “REAR BODYWORK, MUDGUARD” in chapter 3 2. Drain: • fuel (from drain screw ) 3. Disconnect: • autochoke lead coupler • fuel hose • vacuum hose • oil delivery hose • throttle cable (with throttle valve) • clamp (fixing clip) CARB 4. Remove: • carburetor DISASSEMBLING THE CARBURETOR 1. Remove: • float chamber 2. Remove: • float pin • float • needle valve 3.
CARBURETOR CARB 4. Remove: • throttle stop screw (with spring, washer and o-ring) • pilot air screw (with spring) 5. Remove: • spring seat • jet needle • throttle valve • throttle valve spring EAS00485 CHECKING THE CARBURETOR 1. Check: • carburetor body Dirty Clean NOTE: For cleaning, use a petrol based solvent. Clean the pipes and jets with compressed air 2. Check: • main jet • needle jet • pilot jet Dirty Clean 3.
CARBURETOR CARB 4. Check: • throttle valve Wear/Damage Change 5. Check: • throttle valve displacement Irregular movement/Catches Change Insert the throttle valve in the body and check its displacement. 6. Check: • throttle stop screw • pilot air screw • jet needle • starter plunger Wear/Damage Change 7. Measure: • Float height a Outside specifications float and valve seat Check valve, Float height a 15.0 mm ~ 17.
CARBURETOR CARB NOTE: The arm of the float should be supported on the valve without compressing it. • If the height of the float is not within the specified limits, inspect the valve and its seat. • Substitute both parts if any part of them is worn. • If both are in good condition, replace the float. • Check the height of the float again. NOTE: The height of the float is adjusted in the factory. Do not try to modify it under any circumstances.
CARB CARBURETOR EAS00503 CHECKING THE AUTOCHOKE UNIT NOTE: When checking the autochoke unit, the ambient temperature must be lower than 45°C (113°F). 1. Remove: • carburetor 2. Check: • autochoke unit a. Connect a 3.3 mm hose to the starter air passage and blow into the hose. NOTE: When the starter plunger is open, air should come out of the other side of the starter air passage.
CARBURETOR/ FUEL COCK CARB EAS00492 INSTALLING THE CARBURETOR 1. Adjust: • engine idling speed Engine idling speed 1.800 rpm Refer to “ADJUSTING HE ENGINE IDLING SPEED” in chapter 3. 2. Adjust: • throttle cable free play Throttle cable free play (at the flange of the throttle grip) 2 ~ 5 mm Refer to “ADJUSTING HE ENGINE IDLING SPEED” in chapter 3. EAS00505 FUEL COCK CHECKING THE FUEL COCK 1. Stop the engine. 2. Remove: • helmet box Refer to chapter 3, “REAR BODYWORK, MUDGUARD” section. 3.
REED VALVE CARB REED VALVE REMOVING THE REED VALVE 1. Remove: • helmet box Refer to “REAR BODYWORK, MUDGUARD” in chapter 3. • air filter box assembly 2. Remove: • carburetor See section “REMOVING THE CARBURETOR” 3. Remove: • carburetor joint • reed valve assembly CHECKING THE REED VALVE 1. Inspect: • carburetor joint Damage/Cracks Change • reed valve Fatigue/Cracks Change Inspection steps: • Visually inspect the reed valve.
REED VALVE CARB 2. Measure: • valve stopper height Out of specification Adjust the stopper/Replace the valve stopper. Height of valve stopper 6.0 ~ 6.4 mm 3. Measure: • clearance of reed valve Out of specification Replace the reed valve. Clearance of reed valve Less than 0.2 mm INSTALLING THE REED VALVE When the reed valve assembly is installed, reverse the removal procedure. Bear in mind the following points. 1. Install: • gasket New 2.
CHAS 6
CHAS CHAPTER 6 CHASSIS FRONT WHEEL …………………………………………………………………6-1 EXTRACTION …………………………………………………………………6-2 INSPECTION……………………………………………………………………6-2 INSTALLATION …………………………………………………………………6-3 REAR BRAKE ……………………………………………………………………6-4 CHANGE OF BRAKE BLOCKS ………………………………………………6-5 DISASSEMBLY OF CALLIPER ………………………………………………6-6 INSPECTION AND REPAIR …………………………………………………6-7 ASSEMBLY OF CALLIPER ……………………………………………………6-7 ASSEMBLY OF PUMP ………………………………………………………6-8 REAR WHEEL ……………………………………………………………………6-9 EXTRACTION ……………………
FRONT WHEEL CHASSIS FRONT WHEEL Tyre Oil seal Spacer 10 Nut 11 Washer Wheel axle Speedometer gear unit Bearing Spacer Hub Rim assembly TYRE SIZE: 120/70/12 RIM RUN-OUT LIMIT: Vertical: 1.0 mm Lateral: 1.0 mm WHEEL AXLE BEND LIMIT: 0.
FRONT WHEEL CHAS REMOVAL 1. Remove: • brake caliper • Axle • Wheel NOTE: Do not press the brake lever when the wheel is removed from the scooter, otherwise the brake blocks will be closed under force. INSPECTION 1. Measure: • Bend of wheel axle Outside specified value Change Bend limitof wheel axle 0.25 mm s WARNING Do not try to straighten a bent axle 2. Measure: • Run out of wheel Outside specified value Change Run-out limit: Vertical: 1.0 mm Lateral: 1.0 mm 3.
FRONT WHEEL CHAS INSTALLATION Reverse the removal process. Bear in mind the following points. 1. Lubricate: • Front wheel axle • Bearings • Oil seal (edges) • Drive gear (speedometer) Recommended lubricant: Grease with lithium soap base 2. Install: • Speedometer gear unit NOTE: Ensure that the two projections in the gear unit are engaging with the flat surface of the gear unit. 3.
FRONT BRAKE FRONT BRAKE Retaining bolt Bleed screw Calliper assembly Block spring Pad set Piston seal Piston Brake disc Master cylinder cap 10 Diaphragm 11 Hose 12 Brake pump assembly 13 Assembly plate 14 Copper washer 15 Assembly bolt 16 Brake light switch cable TYPE OF BRAKE FLUID DOT 3 or 4 WEAR LIMIT OF BRAKE PADS: 0.8 mm WEAR LIMIT OF BRAKE DISC: 3.
FRONT BRAKE CHAS EAS00583 REPLACING THE FRONT BRAKE PADS NOTE: When replacing the brake pads, it is not necessary to disconnect the brake hose or disassemble the brake caliper. 1. Remove: • brake pad cover • brake pad clip • brake pad pin • brake pad spring 2. Remove: • brake pads (along with the brake pad shims ) 3. Measure: • brake pad wear limit a Out of specification Replace the brake pads as a set. Brake pad wear limit 0.5 mm 4.
FRONT BRAKE CHAS NOTE: a on the brake pad shim The triangle mark must point in the direction of disc rotation. e. Install new brake pads and a new brake pad spring . b NOTE: b of the brake pad spring The arrow mark must point in the direction of disc rotation. 5. Install: • brake pad pins • brake pad clips • brake pad cover 6. Chek: • brake fluid level Below the minimum level mark Add the recommended brake fluid to the proper level.
FRONT BRAKE CHAS CHECKING THE BRAKE HOSE 1. Check: • brake hoses cracks/damage/wear Replace. BRAKE HOSE ASSEMBLY s WARNING • All internal parts should be cleaned only in new brake fluid. • Internal parts should be lubricated with brake fluid when installed. Recommended brake fluid DOT 4 2 3 1. Install: • Brake hose • Copper washers • Assembly bolts • Brake switch 1 Assembly bolt: 2.
FRONT BRAKE CHAS CHECKING THE BRAKE DISC 1. Measure: • Deflection of brake disc Outside specified value Inspect runout of wheel. If the wheel is in good condition, change the brake disc Maximum deflection 0.5 mm • Brake disc thickness Outside specified value Minimum thickness 3.0 mm Bolt (brake disc) 2.
REAR WHEEL CHAS REAR WHEEL Brake shoe Brake cam Shoe axle Wear indicator 10 Brake lever Flat washer Valve Nut Flat washer Return spring TYRE SIZE: 130/70-12 BRAKE DRUM WEAR LIMIT: 110.5 mm BRAKE SHOE WEAR LIMIT: 2.0 mm WHEEL RUN-OUT LIMIT: Vertical: 1.0 mm Lateral: 1.
REAR WHEEL CHAS REMOVAL 1. Remove: • Exhaust pipe assembly 2. Loosen: • Rear axle nut NOTE: When the axle nut is loosened, apply rear brake. 3. Remove: • Rear wheel 4. Remove: • Rear brake cable • Brake shoes • Flat washer INSPECTION 1. Inspect: • Wheel See “INSPECTION OF REAR WHEEL” section 2. Measure: • Wheel run-out See “INSPECTION OF REAR WHEEL” section Rim run-out limits: Vertical: 1.0 mm Lateral: 1.0 mm 3.
REAR WHEEL CHAS 5. Measure: • Thickness of brake shoes a Outside specified value Change Brake shoes thickness 4.0 mm Limit: 2.0 mm 6. Inspect: • Drum brake iner surface Oil/Scratches Change 7. Measure • Drum brake inner diameter a: Out of specification Change Wear limit of brake drum 110.5 mm ASSEMBLY When the brake shoe carrier plate is assembled, reverse the removal procedure. Bear in mind the following points. 1.
REAR WHEEL CHAS Bolt (cam lever): 0.7 m • kg 4. Install: • Flat washer • Brake cable INSTALLATION When installing the rear wheel, reverse the removal procedure. The following points should be remembered. 1. Install: • Rear wheel • Flat washer • Nut Nut (Rear wheel axle): 12.5 m • kg 2. Install: • Silencer Bolt (exhaust pipe side): 0.9 m • kg Bolt (silencer side): 2.6 m • kg 3. Adjust: • Free play of rear brake lever See section in chapter 3 “CHECKING FREE PLAY OF REAR BRAKE LEVER”.
FRONT FORK CHAS FRONT FORK Front fork assembly (left) Rubber cap Restraining ring Restraining ring Cap O-ring Dust guard Retainer Oil seal 10 Fork spring 11 Sliding metal 12 Shock absorber rod 13 Return spring 14 Bar 15 Oil lock piece 16 Outer tube 17 Front fork assembly (right) FREE LENGTH OF FORK SPRING: LIMIT: LEFT 226 mm RIGHT 226 mm FORK OIL CAPACITY: 50 cc ± 1 cc GRADE: 10 W oil fork or equivalent 6-13
FRONT FORK CHAS REMOVAL 1. Place the scooter on its central stand and place an adequate support under the engine 2. Remove: • Brake callipers Consult “FRONT BRAKE REMOVAL” section 3. Remove: • Front wheel See “FRONT WHEEL REMOVAL SECTION” 4. Remove: • Mudguard, front fairing See chapter 3 “FRONT BODYWORK, MUDGUARD” 1 5. Loosen: • Positioning bolt (fork) 6. Remove: • Restraining ring • FRONT FORK 2 3 DISASSEMBLY 1. Remove: • Rubber cap • Restraining ring • Cap • Fork spring 2.
CHAS FRONT FORK 4. Remove: • Bolt (shock absorber rod) • Copper washer NOTE: Remove the bolt (shock absorber rod) while the shock absorber rod is held with the Thandle and a support T-handle: 90890-01326 Support: 90890-01294-A 5. Remove: • Inner pipe • Shock absorber rod • Oil lock piece (left side) • Oil seal INSPECTION 1.
FRONT FORK CHAS ASSEMBLY Reverse the disassembly procedure. Bear in mind the following points. NOTE: • When assembling the fork, ensure that the following new parts are used. • Oil seal • Mudguard • Sliding metal • Ensure that all components are clean before assembly. 1. Install: • Shock absorber rod • Oil lock piece (left side) • Bar • Copper washer (new) • Bolt (shock absorber rod) Bolt (hydraulic rod): 23 Nm (2.
FRONT FORK CHAS 3. Install: • Retainer • Dust guard NOTE: Couple the retainer correctly on the groove of the outer tube . 4. Fill : • Fork oil Each fork: 50 cm3 10 W fork oil or equivalent after filling, slowly pump the fork to distribute the oil. Oil level: 95 mm From the upper part of the inner fork tube totally compressed without the spring. NOTE: Place the fork in a vertical position. 5.
FRONT FORK CHAS INSTALLATION Reverse the removal procedure. The following points should be remembered 1. Install: • Front fork: • Stopper ring NOTE: Attach the stopper ring correctly on the inner tube groove. 2. Tighten: • Positioning bolt (lower bracket) Positioning bolt (inner lever arm) 30 Nm (3.0 m • kg, 22 ft • lb) 3.
HANDLEBAR AND STEERING CHAS HANDLEBAR AND STEERING 11 Lock washer 12 Center ring nut 13 Rubber washer 14 Lower ring nut 15 Bearing cover 16 Upper bearing race 17 Bearing cage 18 Bearing race 19 Lower bracket Handlebar Grip cap Throttle grip Throttle grip guide Grip Nut Bolt Throttle cable Brake cable 10 Upper ring nut 10 11 13 15 17 16 18 12 14 16 18 17 19 6-19
HANDLEBAR AND STEERING CHAS REMOVAL 1. Place the scooter on its central stand and place a suitable support under the engine. 2. Remove: • Front wheel See section “REMOVAL OF FRONT WHEEL” 3. Remove: • Mudguard • Front fairing See chapter 3,“FRONT BODYWORK, MUDGUARDS” section. 4. Remove: • Handlebar covers See chapter 3 “HANDLEBAR COVER” section NOTE: Before completely removing the rear cover with the speedometer, disconnect the speedometer cable and the signalling and lighting system cables. 5.
HANDLEBAR AND STEERING CHAS 8. Remove: • Upper ring nut Ring nut wrench for steering 90890-01403 s WARNING Support the steering axle so that it does not fall. 9. Remove: • Lock washer • Central ring nut • Rubber washer • Lower ring nut • Bearing cover • Lower bracket INSPECTION 1. Wash the bearing and race with solvent. 2.
HANDLEBAR AND STEERING CHAS NOTE: • Always change the bearing and the races together. • Change the mudguard whenever the steering head is disassembled. ATTENTION: If the bearing race is not coupled correctly, the steering tube may be damaged. 3. Inspect: • Lower lever arm (with steering rod) Cracks/Damage Change 4. Inspect: • Handlebar Cracks/Damage Change s WARNING Do not try to straighten a bent handlebar since this can weaken it dangerously.
HANDLEBAR AND STEERING CHAS 3. Tighten: • Steering nut Steps for tightening the steering nut: 1. Tighten the lower ring nut to 3.8 m•kg. 2. Loosen the lower ring nut 1/2 of a turn and tighten to 0.65 m•kg. 3. Check the steering for smooth operation. 4. Install rubber washer . 5. Install central ring nut and hand tighten untill the lower and central ring nuts slots allignet. 6. Install the lock washer . 7.
HANDLEBAR AND STEERING CHAS 7. Install: • Brake pump 1 NOTE: First tighten the upper bolt, then the lower bolt. Bolt (brake pump) 0.9 m • kg 8. Install: • Rear handlebar cover with speedometer • Front handlebar cover NOTE: Connect the speedometer cables, signalling and lighting systems. ATTENTION: Situate the speedometer cable through its housing in the rear cover. 9. Install: • Front fork See “INSTALLATION OF FRONT FORK SECTION”. 10.
ELEC 7
ELEC CHAPTER 7 ELECTRICAL SYSTEM ELECTRICAL COMPONENTS …………………………………………………7-1 IGNITION AND STARTER SYSTEM……………………………………………7-3 CIRCUIT DIAGRAM ……………………………………………………………7-3 IGNITION AND STARTER CIRCUIT SYSTEM ………………………………7-4 TROUBLESHOOTING …………………………………………………………7-5 CHARGING SYSTEM …………………………………………………………7-10 CIRCUIT DIAGRAM …………………………………………………………7-10 LOCATION AND REPAIR OF FAULTS ……………………………………7-11 LIGHTING SYSTEM ……………………………………………………………7-13 CIRCUIT DIAGRAM …………………………………………………………7-13 LOCATION AND REPAIR OF FAU
ELECTRICAL COMPONENTS ELEC ELECTRICAL SYSTEM ELECTRICAL COMPONENTS Wire harness Starter motor CDI unit Engine oil level gauge Starter relay Fuel level gauge Battery Ignition coil BATTERY SPECIFIC GRAVITY: 1,280 IGNITION COIL: PRIMARY COIL RESISTANCE: 0.56 ~ 0.84 Ω at 20 °C (68 °F) SECONDARY COIL RESISTANCE: 5.7 ~ 8.
ELECTRICAL COMPONENTS Main switch/seat lock Turn signal relay Rectifier/regulator Horn 7-2 ELEC
IGNITION AND STARTER SYSTEM IGNITION AND STARTER SYSTEM CIRCUIT DIAGRAM . CDI magneto . CDI . Spark plug . Main switch . Fuse . Battery . Starter relay 10 . 11 . 24 . 25 . 34 .
ELEC IGNITION AND STARTER SYSTEM SISTEMA DE ENCENDIDO Y ARRANQUE 11 Starter switch 12 Main switch 18 Front brake switch 19 Rear brake switch B Pick-up coil G To oil level switch Spark plug Ignition coil CDI unit Starter motor Starter relay Fuse 10 Battery INDUCED COIL RESISTANCE: 0.05 ~ 0.06 _ at 20 °C (68 °F) BRUSH WEAR LIMIT: 0.9 mm COMMUTATOR WEAR LIMIT: 16.6 mm MICA LOWER CUT-OFF: 1.
IGNITION AND STARTER SYSTEM ELEC TROUBLESHOOTING IF THE IGNITION SYSTEM IS NOT OPERATING (NO SPARK OR INTERMITTENT SPARK) NOTE: • Remove the following parts before carrying out the repair of fault . 1) Side covers (right and left) 2) Rear cover 3) Footrest panel • Use the following special tools to repair faults. Ignition tester: 90890-06754 Pocket tester: 90890-03112 Standard spark plug BR7HS (NGK) 1. Spark plug • Check spark plug conditions. • Check type of spark plug.
IGNITION AND STARTER SYSTEM ELEC 3. Spark plug cap resistance • Remove spark plug cap • Connect the pocket tester (Ωx1k) on the spark plug cap. • Check if the spark plug pipe has the specified resistance Resistance of spark plug: 5 kΩ at 20 °C (68 °F) SATISFIES THE SPECIFIED VALUE OUTSIDE SPECIFIED VALUE Replace the spark plug cap 4. Resistance of ignition coil • Disconnect the ignition coil cables. • Connect the pocket tester (Ωx1) on the ignition coil .
IGNITION AND STARTER SYSTEM ELEC 5. Pick up coil resistance • Disconnect the Pick up coil coupler of the installation • Connect the pocket tester (Ωx100) on the pick up coil terminal. Cable (+) of tester White blue Cable (–) of tester Black • Check if the pick up coil has the specified resistance. OUTSIDE SPECIFIED VALUE Resistance of harnessing coil 250 ~ 370 Ω at 20 °C (68 °F) The pick up coil is defective, replace it SATISFIES THE SPECIFIED VALUE 6.
IGNITION AND STARTER SYSTEM ELEC THE STARTER MOTOR DOES NOT FUNCTION NOTE: • Remove the following parts before repairing the faults. 1) Side covers (right and left) 2) Rear cover 3) Front mudguard 4) Handlebar cover (upper) • Use the following special tool for these repairs. Pocket tester: 90890-03112 1. Fuse • Remove the fuse. • Connect the pocket tester (Ωx1) on the fuse. • Check the fuse to see if there is continuity. NO CONTINUITY The fuse is defective CONTINUITY 2.
IGNITION AND STARTER SYSTEM ELEC 4. Starter relay • Disconnect the starter relay cable from the installation. • Connect the battery to the starter relay cables as shown using the bridge cables . • Check the operation of the starter motor. INCORRECT The main switch is defective, change. DOES MOVE 5. Main switch • Disconnect the coupler of the main switch from the installation. • Check the switch component to see if there is continuity between “Red and Brown ”.
CHARGING SYSTEM CHARGING SYSTEM CIRCUIT DIAGRAM Flywheel Magneto Fuse Battery Rectifier/Regulator 7-10 ELEC
CHARGING SYSTEM ELEC TROUBLESHOOTING THE BATTERY IS NOT CHARGED NOTE: • Remove the following parts before carrying out the repair of the fault. 1) Side covers (right and left) 2) Rear cover • Use the following special tool for this repair. Inductive tachometer: 90890-03113 Pocket tester: 90890-03112 1. Fuse (main) • Remove the fuse. • Connect the pocket tester (Ωx1) to the fuse. • Check the fuse to see if there is continuity NO CONTINUITY The fuse is defective, change. CONTINUITY 2.
CHARGING SYSTEM ELEC 4. Charge coil resistance • Disconnect the charge coil coupler from the installation. • Connect the pocket tester(Ωx1) on the charge coils. • Measure the resistances of the charge coil. Cable (+) of the tester White cable Cable (–) of tester Yellow/Red Cable Charge coil resistance: 0,288 ~ 0.432 Ω at 20 °C (68 °F) OUTSIDE SPECIFIED VALUE SATISFIES THE SPECIFIED VALUE The charge coil is defective, change 5.
LIGHTING SYSTEM LIGHTING SYSTEM CIRCUIT DIAGRAM Flywheel 14 Light dinmer switch 16 Headlamp 21 Brake and rear light 27 Meter light 7-13 ELEC
LIGHTING SYSTEM ELEC TROUBLESHOOTING HEADLAMP, “HIGH BEAM” LIGHT INDICATOR, REAR LIGHT AND/OR METER LIGHT DO NOT LIGHT UP NOTE: • Remove the following parts before repairing the faults. 1) Side covers (right and left) 2) Rear cover 3) Handlebar cover (upper) • Use the following special tool for these repairs. Pocket tester: 90890-03112 1. Light switch “k j” • Disconnect the coupler of the main switch (left) from the installation. • Place the switch “k j” in position “j”.
LIGHTING SYSTEM ELEC 3. Connections Check the connections throughout the lighting system. See “ELECTRICAL DIAGRAM” section BAD CONNECTION Correct CORRECT The circuit is in good condition CHECKING LIGHTING SYSTEM 1. The headlight does not light NO CONTINUITY 1. Bulb and bulb holder • Check the bulb and bulb holder to see if there is continuity. Replace the bulb and/or bulb holder. CONTINUITY 2. Voltage • Connect the pocket tester (20 V AC) on the headlight.
LIGHTING SYSTEM ELEC 2. The panel light does not light. NO CONTINUITY 1. Bulb and bulb holder • Check the bulb and bulb holder to see if there is continuity. Replace the bulb and/or bulb holder. CONTINUITY 2. Voltage • Connect the pocket tester (20 V AC) on the bulb holder coupler. Cable (+) of the tester Blue terminal Cable (–) of tester Black terminal • Place the main switch on “ON” • Check if there is a voltage (12 V) in the “Blue cable” of the connector of the bulb holder.
SIGNALLING SYSTEM SIGNALLING SYSTEM CIRCUIT DIAGRAM Speed sensor Main switch Fuse Battery 13 Horn 13 “HORN” switch 15 “TURN” switch 17 Front indicator light (Left) 18 Front indicator light (Right) 19 Rear indicator light (Left) 20 21 22 23 24 25 26 27 28 7-17 Rear indicator light (Right) Tail light Horn Indicator relay Front brake switch Rear brake switch Oil level switch Motor lights Fuel sensor ELEC
SIGNALLING SYSTEM ELEC TROUBLESHOOTING • INDICATOR LIGHT, BRAKE LIGHT, AND/OR INDICATING LIGHTS DO NOT LIGHT. • THE HORN DOES NOT SOUND NOTE: • Remove the following parts before repairing the faults . 1) Front cover . 4) Front lower fender 2) Inner cover 3) Rear panel (battery box) • Use the following special tool for the repairs. Pocket tester: 90890-03112 1. (Main) fuse • Remove the fuses. • Connect the pocket tester (Ωx1) on the fuses. • See “INSPECTION OF FUSES” in chapter 3.
SIGNALLING SYSTEM ELEC 4. Connections • Check the connections throughout the signalling system. • See the “ELECTRICAL DIAGRAM”section BAD CONNECTION Repair CORRECT Check the conditions for each signalling system circuit. Consult the “CHECKING SIGNALLING SYSTEM” section. CHECKING SIGNALLING SYSTEM 1. Horn does not operate 1.“HORN” switch. • Disconnect the coupler of the handlebar switch (left) from the installation and horn cable.
SIGNALLING SYSTEM ELEC 3. Horn • Disconnect the “Pink” cable from the horn terminal. • Connect a bridge cable on the horn terminal and earth the bridge cable. • Place the main switch on “ON”. THE HORN SOUNDS The horn is in good condition. THE HORN DOES NOT SOUND. 4. Voltage • Connect the pocket tester (20 V DC) on the horn, on the “Pink” terminal. Cable (+) of tester Pink Cable (–) of tester Earth of frame • Place main switch on “ON”.
SIGNALLING SYSTEM ELEC INCORRECT The brake switch is defective, change. CORRECTO 3.Voltage • Connect the pocket tester (20 V DC) on the bulb holder connector. Cable (+) of tester Green/Yellow Cable (–) of tester Black • Place the main switch on “ON”. • Activate the brake lever. • Check if there is a voltage (12 V) on the “Green/Yellow” cable of the bulb holder connector.
SIGNALLING SYSTEM ELEC INCORRECT The “TURN” is defective, change the handlebar switch (left). 3.Voltage • Connect the pocket tester (20 V DC) on the flasher relay . Cable (+) of tester Brown Cable (–) of tester Fame ground • Place the main switch on “ON”. • Check if there is a voltage (12 V) on the “Brown” cable and “Frame ground” of the flasher relay terminal. OUTSIDE SPECIFIED VALUE SATISFIES THE SPECIFIED VALUE (12 V) The indicator relay is defective, change 4.
SIGNALLING SYSTEM • Place the main switch on “f”. • Place the switch “b” on position “c” or “d”. • Check if there is a voltage (12 V) on the “Chocolate” or “Dark Green” cable of the bulb holder connector. ELEC OUTSIDE SPECIFIED VALUE SATISFIES THE SPECIFIED VALUE (12 V) The connection circuit from the “TURN” switch to the bulb holder connector is defective, review. The circuit is in good condition. 4. The oil indicator light “OIL” does not light. 1.
SIGNALLING SYSTEM • Place main switch on “*” • Check if there is a voltage (12 V) on the “Gray” cable of the bulb holder connector OUTSIDE SPECIFIED VALUE SATISFIES THE SPECIFIED VALUE (12 V) 4. Connections • Check the connections throughout the signalling system. See the “ELECTRICAL DIAGRAM” section. The circuit is in good condition. 5. The speedometer fails to come on. 1. Voltage • Connect the pocket tester (DC 20 V) to the multi-function meter socket coupler (wire harness side) as shown.
SIGNALLING SYSTEM 2. Speed sensor • Connect the pocket tester (DC 20 V) to the speed sensor coupler (wire harness side) as shown. Positive tester probe blue/green Negative tester probe black/yellow L B R L/ B/ R/ G Y Y • Set the main switch to “ON”. • Elevate the front wheel and slowly rotate it. • Measure the voltage (DC 12 V) of red/yellow and black/yellow. With each full rotation of the front wheel, the voltage reading should cycle from 0 V to 5 ~ 11V to 0 V to 5 ~ 11V, etc.
? LOC AVER 8
LOC AVER CHAPTER 8 LOCATION AND REPAIR OF BREAKDOWNS LOCATION AND REPAIR OF ENGINE BREAKDOWNS ……………………8-1 ELECTRICAL SYSTEM ………………………………………………………8-1 COMPRESSION SYSTEM ……………………………………………………8-2 INLET AND EXHAUST SYSTEM ……………………………………………8-3 ELECTRICAL DIAGRAM YN50
TROUBLE SHOOTING LOC AVER ELECTRICAL SYSTEM IGNITION COIL • The primary and secondary coils are broken or defective. • The high voltage cable is defective. • The spark plug cap is defective. * CHECK ALL CABLE CONNECTIONS MAIN SWITCH • The main switch is short circuited. SPARK PLUG • Excessive carbon deposits. • Damp electrodes. • Incorrect gap. • Broken. SOURCE COIL • The coils are broken. PICK-UP COIL • The coils are broken. • Incorrect ignition distribution.
TROUBLE SHOOTING LOC AVER COMPRESSION SYSTEM FATIGUE/CRACKS DEFECTIVE SEALING DAMAGE DAMAGE/WEAR DAMAGE/WEAR WEAR/CRACKS/DAMAGE DAMAGE WEAR/STRIPING INSUFFICIENT TIGHTENING TORQUE WEAR/CATCHING/BREAKS CARBON DEPOSITS DAMAGE WARPING/CARBON DEPOSITS 8-2
TROUBLE SHOOTING LOC AVER INLET AND EXHAUST SYSTEM FUEL TANK CAP • Obstructed FUEL COCK • Obstructed DAMP TYPE FUEL PIPE • Obstructed AIR FILTER ELEMENT • Dirty or obstructed CARBURETTOR JOINT • Air leaks MUFFLER • Obstructed EXHAUST PIPE • Cracked or broken • Carbon deposits (CARBURETTOR) NEEDLE • Badly adjusted (Average speed) AIR SCREW • Badly adjusted (Idling and starting) MAIN JET • Incorrect size • Obstructed (High speed) ACCELERATOR STOPPING SCREW • Badly adjusted (Idling and starting) FLO
ELECTRICAL DIAGRAM YN50 COLOUR CODE COMPONENTS B ...............................BLACK R ...............................RED L................................BLUE G...............................GREEN O...............................ORANGE Y ...............................YELLOW P ...............................PINK BR.............................BROWN CH ............................CHOCOLATE SB.............................SKY BLUE DG ............................DARK GREEN W ..............................
