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EAS00002 NOTICE This manual was produced by the Yamaha Motor España, S.A., primarily for use by Yamaha/MBK dealers and their qualified mechanics. It is not possible to include all the knowledge of a mechanic in one manual. Therefore, anyone who uses this book to perform maintenance and repairs on Yamaha/MBK vehicles should have a basic understanding of the mechanics and the techniques to repair these types of vehicles.
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EAS00007 HOW TO USE THIS MANUAL FORMAT OF THIS MANUAL This manual consists of chapters for 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.
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EAS00008 ILLUSTRATED SYMBOLS (See illustration) SPEC INFO The symbols from are designed as thumb indices, to indicate the chapter num- ber and index. General information Specifications Periodic checks and adjustments General motor revision Cooling system COOL CARB Carburetor Chassis Electrical system Troubleshooting CHAS ELEC...
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EAS00010 TABLE OF CONTENTS GENERAL INFORMATION INFO SPECIFICATIONS SPEC PERIODIC CHECKS AND ADJUSTMENTS ENGINE COOLING SYSTEM COOL CARBURETOR CARB CHASSIS CHAS ELECTRICAL SYSTEM ELEC TROUBLESHOOTING TRBL SHTG...
INFO CHAPTER 1 GENERAL INFORMATION SCOOTER IDENTIFICATION……………………………………………………1-1 FRAME SERIAL NUMBER ……………………………………………………1-1 ENGINE SERIAL NUMBER……………………………………………………1-1 IMPORTANT INFORMATION …………………………………………………1-2 REPLACEMENT PARTS ………………………………………………………1-2 GASKETS, OIL SEALS AND O-RINGS ……………………………………1-2 LOCK WASHERS/PLATES AND COTTER PINS……………………………1-2 BEARINGS AND OIL SEALS …………………………………………………1-2 CIRCLIPS ………………………………………………………………………1-3 SPECIAL TOOLS …………………………………………………………………1-4...
IDENTIFICATION OF SCOOTER INFO EAS00015 GENERAL INFORMATION SCOOTER IDENTIFICATION FRAME SERIAL NUMBER The frame serial number is stamped on the chassis. ENGINE SERIAL NUMBER The serial number of the engine is stamped on the raised portion of the rear left section of the transmission box.
IMPORTANT INFORMATION INFO IMPORTANT INFORMATION EAS00021 REPLACEMENT PARTS 1. Use only genuine Yamaha/MBK parts for all replacements. Use the oil and/or grease recommended Yamaha/MBK assembly and adjustment. EAS00022 GASKETS, OIL SEALS AND O-RINGS 1. Replace all gaskets, seals and O-rings when overhauling the engine.
IMPORTANT INFORMATION INFO EAS00025 CIRCLIPS 1. Check all circlips carefully before reas- sembly. Always replace piston pin clips after one use. Replace distorted circlips. When installing a circlip , make sure that the sharp-edged corner is positioned opposite the thrust it receives.
SPECIAL TOOLS INFO EAS00027 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 inappropria- te tools or improvised techniques. When placing an order, refer to the list provided below to avoid any mistakes.
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Ignition checker This instrument is necessary to check the components of the ignition system. 90890-85505 Yamaha bond No. 1215 This bond (sealant) is used for crankcase mating surface, etc. 90890-01348 Locknut wrench This tool is used to loosen and tighten the secondary sheave nut.
SPEC GENERAL SPECIFICATIONS SPECIFICATIONS GENERAL SPECIFICATIONS Model CS50 CS50Z Dimensions: Overall lenght 1.740 mm Overall widht 675 mm Overall height 1.065 mm Seat height 770 mm / 776 mm Wheelbase 1.210 mm Minimum ground clearance 132 mm Basic weight (With oil and full fuel tank):...
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SPEC GENERAL SPECIFICATIONS Model CS50 CS50Z Chassis: Frame type Steel tube underbone Front axle incline angle 25° Steering angle base 80 mm Tire: Size/Type (Front) 110/70-12 / 47 L Size/Type (Rear) 120/70-12 / 51 L, 130/70-12 / 56 L Tire pressure (cold tire):...
SPEC MAINTENANCE SPECIFICATIONS CHASSIS Model CS50 CS50Z Steering system: Steering bearing type Upper Ball bearing Lower Ball bearing Front suspension: Front fork travel 70 mm Fork spring free length 224 mm Spring rate 1,33 Kgf/mm 2,0 Kgf/mm Oil capacity 45 cc ± 1...
CONVERSION TABLE / SPEC GENERAL TIGHTENING TORQUES SPECIFICATIONS EAS00028 EAS00029 CONVERSION TABLE GENERAL TIGHTENING TORQUE SPECIFICATIONS All specification data in this manual are listed in SI and METRIC UNITS. This chart specifies tightening torques for Use this table to convert METRIC unit data to standard fasteners with a standard ISO thread IMPERIAL unit data.
SPEC TIGHTENING TORQUES TIGHTENING TORQUES ENGINE TIGHTENING TORQUES Tightening Thread torque Part to be tightened Part name Q’ty Remarks size m•kg Spark plug – M 14 Cylinder head and cylinder Cylinder Stud Air protector 2 (A/C) Screw Air protector 3 (A/C) Screw Fan (A/C) Screw...
SPEC TIGHTENING TORQUES CHASSIS TIGHTENING TORQUES Tihtening torque Part to be tightened Thread size Remarks m•kg Frame, Engine and Parts Frame with bracket 3 M10 x 1.25 Engine bracket 3 with the engine M12 x 1.25 Cushion and related parts Rear shock absorber M10 x 1.25 31.5...
SPEC CABLE ROUTING CABLE ROUTING Front brake hose Insert the three tubes through the clamp Rear brake cable Connect the oil hose to the carburettor Front brake calliper Set the intake hose under the reinforcement Front mudguard (L/C) Taillight Clamp the fuel pipe to the carburettor Vacuum pipe Tighten together the ground cable and the Fuel pipe...
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SPEC CABLE ROUTING CABLE ROUTING Rectifier / Regulator Clamp the wire harness, brake cable and Main switch throttle to the frame Fuel level gauge Clamp the oil hose to the tank Horn Connect the oil hose to the pump Ignition coil Tie both ends Spark plug wire Tighten together the ground cable and the...
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SPEC CABLE ROUTING CABLE ROUTING Front brake switch Throttle tension cable. Cover then adjust Wire harness Connect the brake switch cables in this Throttle cable area Rear brake cable Do not pass the brake hose through Front brake hose the clamp 2-13...
• Check operation. and switches • Adjust headlight beam. *: It is recommended that these items be revised by an authorized Yamaha/MBK dealer. **: Apply grease for mid-weight bearings. NOTE: • The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
REAR BODYWORK, MUDGUARD REAR BODYWORK, MUDGUARD REMOVAL 1. Remove: • seat 2. Remove: • central panel NOTE: Slide the panel to the front. 3. Remove: • rear fender 4. Remove: • oil tank cap and grommet • fuel tank cap and grommet •...
REAR BODYWORK, MUDGUARD 5. Remove: • side covers (4 bolts) NOTE: Remove carefully the hook between side cover and tail light. 6. Remove: • battery cover , leads and battery • oil tank fixing bolt NOTE: Fix the oil tank to the frame with a band. •...
FRONT COWLING AND FOOTREST FRONT COWLING AND FOOTREST REMOVAL 1. Remove: • front upper cowling NOTE: Disconect front light and indicator light cou- plers. 2. Remove: • front middle cowling 3. Remove: • lower cowling 4. Remove: • under cowling...
FRONT COWLING AND FOOTREST 5. Remove: • legshield NOTE: Remove first the main switch cover 6. Remove: • hook bracket 7. Remove: • footrest INSTALLATION Reverse the removal process NOTE: After installing all plastic parts, check that all hooks are properly attached.
Turn the pilot screw out the specified num- ber of turns. Pilot air screw setting CS50: Dellorto 2 - 2 Gurtner 1 CS50Z: Dellorto 1 ± d. Turn the throttle stop screw...
ADJUSTING THE THROTTLE CABLE FREE PLAY EAS00058 ADJUSTING THE THROTTLE CABLE FREE PLAY NOTE: Prior to adjusting the throttle cable free play, the engine idling speed should be adjusted. 1. Check: • throttle cable free play k a Out of specification Adjust.
CHECKING THE SPARK PLUG EAS00060 CHECKING THE SPARK PLUG 1. Disconnect: • spark plug cap 2. Remove: • spark plug CAUTION: Before removing the spark plug, blow away any dirt accumulated in the spark plug well with compressed air to prevent it from falling into the cylinder.
The “OIL CAUTION” indicator light is lit. Recommended oil: YAMAHA 2T 2-stroke engine oil or equivalent Total: 1.4 L NOTE: After filling the oil tank, close it with the cap and close the seat.
10W30 type SE or higher engine oil or GL gear oil Capacity: 0,11 L CS50 AUTOLUBE PUMP AIR BLEEDING The air bleeding must be done always the oil tank is empty, when the intake lube is discon- nected or the tank is disassembled.
CAUTION: Do not twist the air filter element when squeezing it. • Apply oil for foam air filters or YAMAHA 2T engine oil or equivalent oil for 2 stroke engines. • Wipe off the excess oil. NOTE: The filter should be wet but not dripping.
CHECKING THE COOLANT LEVEL EAS00103 CHECKING THE COOLANT LEVEL (CS50Z only) 1. Stand the scooter on a level surface. NOTE: • Place the scooter on a suitable stand. • Make sure the scooter is upright. 2. Check: • coolant level The coolant level should be between the maximum level mark k a and minimum level mark k b...
CHANGING THE COOLANT EAS00105 CHANGING THE COOLANT (CS50Z only) 1. Remove: • water pump cover • coolant filler cap s WARNING Do not remove the water pump cover when the engine is hot. Scalding hot fluid and steam may be blown out, which could cause serious injury.
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CHANGING THE COOLANT Handling notes for coolant Coolant is potentially harmful and should be handled with special care. s WARNING • If coolant splashes in your eyes, tho- roughly wash them with water and con- sult a doctor. • If coolant splashes on your clothes, quickly wash it away with water and then with soap and water.
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CHANGING THE COOLANT 6. Install: • coolant filler cap 7. Warm it up for several minutes, and then stop it. 8. Check: • coolant level Refer to “CHECKING THE COOLANT LEVEL”. NOTE: Before checking the coolant level, wait a few minutes until the coolant has settled.
ADJUSTMENT THE FRONT BRAKE LEVER/ ADJUSTMEN THE REAR BRAKE LEVER/ CHECKING THE FRONT BRAKE PADS EAS00109 CHASSIS ADJUSTMENT THE FRONT BRAKE LEVER 1. Check: • free play of the front brake lever k a . Brake lever free play (at the end of the brake lever) 2 ~ 5 mm s WARNING...
CHECKING THE REAR BRAKE SHOES/ CHECKING THE BRAKE FLUID LEVEL EAS00126 CHECKING THE REAR BRAKE SHOES 1. Activate the brake lever 2. Check: • wear indicator Indicator on wear limit line Replace the brake shoes. EAS00116 CHECKING THE BRAKE FLUID LEVEL NOTE: Place the scooter upright when inspecting the fluid level.
BLEEDING THE HYDRAULIC BRAKE SYSTEM EAS00133 BLEEDING THE HYDRAULIC BRAKE SYSTEM s WARNING Bleed the hydraulic brake system whene- ver: • the system is disassembled. • a brake hose is loosened, disconnected or replace. • the brake fluid level is very low. •...
CHECKING AND ADJUSTING THE STEERING HEAD EAS00148 CHECKING AND ADJUSTING THE STEERING HEAD 1. Stand the scooter on a level surface. s WARNING Securely support the scooter so that there is no danger of it falling over. NOTE: Place the scooter on a suitable stand so that the front wheel is elevated.
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CHECKING AND ADJUSTING THE STEERING HEAD Lower ring nut (final tightening tor- que) 6.5 Nm (0.65 m • kg) d. Check the steering head for looseness or binding by turning the front fork all the way in both directions. If any binding is felt, remove the lower bracket and check the upper and lower bearings.
CHECKING THE FRONT FORK EAS00163 CHECKING THE TIRES 1. Measure: • air pressure Outside specified value Adjust 158.3 kg (CS50Z) Maximum load*: 161.5 kg (CS50) Pressure cold Front Rear Up to 90 kg 175kpa. 200kpa. (1.75kg/cm (2.0kg/cm 90 kg to 175kpa.
CHECKING AND CHARGING THE BATTERY EAS00179 ELECTRICAL SYSTEM CHECKING AND CHARGING THE BATTERY s WARNING Batteries generate explosive hydrogen gas and contain electrolyte which is made of poisonous and highly caustic sulfuric acid. Therefore, always follow these preventive measures: • Wear protective eye gear when handling or working near batteries.
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CHECKING AND CHARGING THE BATTERY NOTE: Since MF batteries are sealed, it is not possi- ble to check the charge state of the battery by measuring the specific gravity of the electroly- te. Therefore, the charge of the battery has to be checked by measuring the voltage at the battery terminals.
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CHECKING AND CHARGING THE BATTERY 5. Charge: • battery (refer to the appropriate charging method illustration) s WARNING Do not quick charge a battery. CAUTION: • Never remove the MF battery sealing caps. • Do not use a high-rate battery charger since it forces a high-amperage current into the battery quickly and can cause battery overheating and battery plate...
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CHECKING AND CHARGING THE BATTERY Charging method using a variable-current (voltage) charger Measure the open-circuit NOTE: voltage prior to charging. Voltage should be measured 30 minutes after the machine is stopped. Connect a charged and NOTE: AMP meter to the battery Set the charging voltage at 16 ~ 17 V.
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CHECKING AND CHARGING THE BATTERY Charging method using a constant voltage charger Measure the open-circuit NOTE: voltage prior to charging. Voltage should be measured 30 minutes after the machine is stopped. Connect a charged and AMP meter to the battery and start charging.
CHECKING AND CHARGING THE BATTERY/ CHECKING THE FUSE 6. Install: • battery 7. Connect: • battery leads (to the battery terminals) CAUTION: First, connect the positive battery lead and then the negative battery lead 8. Check: • battery terminals Dirt Clean with a wire brush.
REPLACING THE HEADLIGHT BULB/ ADJUSTING THE HEADLIGHT BEAM EAS00182 REPLACING THE HEADLIGHT BULB 1. Remove: • front upper cowling 2. Remove: • headlight bulb holder 3. Remove: • headlight bulb s WARNING Since the headlight bulb gets extremely hot, keep flammable products and your hands away from the bulb until it has cooled down.
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KICKSTARTER ………………………………………………………………4-32 ASSEMBLING THE SECONDARY SHEAVE ………………………………4-33 ASSEMBLING THE PRIMARY SHEAVE……………………………………4-34 INSTALLING THE KICKSTARTER …………………………………………4-36 PISTON, CYLINDER AND CYLINDER HEAD (CS50) ……………………4-37 PISTON, CYLINDER AND CYLINDER HEAD (CS50Z) …………………4-38 PISTON AND PISTON PIN …………………………………………………4-39 CYLINDER AND CYLINDER HEAD ………………………………………4-39 ENGINE REMOUNTING ……………………………………………………4-41...
ENGINE REMOVAL ENGINE REMOVAL 1. Place a suitable stand under the frame. 2. Remove: • rear shock absorber bolt (lower) • engine mounting bolt 3. Remove: • engine NOTE: Lift up the frame and remove the engine. 4. Place the frame on a suitable stand.
ENGINE DISASSEMBLY 2. Remove: • piston pin • piston • piston pin bearing CAUTION: Do not use a hammer to take out the piston pin. REMOVING THE KICKSTARTER SYSTEM 1. Remove: • clamp (air filter) • air filter 2. Remove: •...
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ENGINE DISASSEMBLY 2. Attach: • crankcase puller Crankcase puller 90890-01135 NOTE: Fully tighten the positioning bolts of the tool, but ensure that the tool body is parallel with the box. If necessary, slightly loosen one of the bolts to level the body of the tool. 3.
INSPECTION AND REPAIR INSPECTION AND REPAIR EAS00229 CHECKING THE CYLINDER HEAD 1. Eliminate: • combustion chamber carbon deposits (with a rounded scraper) NOTE: Do not use a sharp instrument to avoid dama- ging or scratching: • spark plug bore threads 2.
INSPECTION AND REPAIR EAS00258 CHECKING THE CYLINDER AND PISTON 1. Eliminate: • carbon deposits Use a rounde scraper 2. Inspect: • cylinder wall Wear/striping Rectify or change 3. Eliminate: • carbon deposits From the piston crown and ring groovers 4. Remove: •...
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Measure piston skirt diameter “P” with the micrometer. k a 5 mm from the bottom edge of the piston. Piston size “P” CS50: 39.952 ~ 39.972 mm Standard CS50Z: 39.957 ~ 39.977 mm d. If out of specification, replace the piston and piston rings as a set.
INSPECTION AND REPAIR EAS00263 CHECKING THE PISTON RINGS 1. Measure: • piston ring side clearance Out of specification Replace the piston and piston rings as a set. Use a Feeler Gauge NOTE: Before measuring the piston ring side clearan- ce, eliminate any carbon deposits from the piston ring grooves and piston rings.
INSPECTION AND REPAIR EAS00265 CHECKING THE PISTON PIN AND PISTON PIN BEARING 1. Check: • piston pin Blue discoloration/grooves Replace the piston pin and then check the lubrication system. 2. Measure: • piston pin outside diameter Out of specification Replace the piston pin.
INSPECTION AND REPAIR AUTOLUBE OIL PUMP Internal wear or poor operation may cause the pump to deviate from its factory adjustment. However, this is very uncommon. If incorrect operation is suspected, inspect the following: 1. Inspect: • supply line Obstruction Apply air under pressure.
INSPECTION AND REPAIR EAS00401 CHECKING THE BEARINGS 1. Check: • bearings Clean and lubricate the bearings, then rota- te the inner race with your finger. Rough movement Replace. EAS00321 CHECKING THE PRIMARY SHEAVE 1. Inspect: • primary sliding pulley wheel •...
INSPECTION AND REPAIR 6. Inspect: • clutch shoes Shiny parts Polish with sand paper. NOTE: After using sand paper, clean off the polished particles with a cloth. 7. Measure: • clutch shoe thickness Outside specified value Replace Clutch shoe thickness 2.0 mm <Wear limit>: 1.0 mm EAS00320...
ENGINE ASSEMBLY AND ADJUSTMENT EAS00419 TRANSMISSION Circlip Secondary sheave axle Bearing Bearing Oil seal Dowel pin Drive axle Gasket Bearing Transmission case cover Main axle Bearing Conical spring washer Oil seal Flat washer 9 Nm (0.9 m • kg) 4-27...
ENGINE ASSEMBLY AND ADJUSTMENT EAS00428 INSTALLING THE TRANSMISSION 1. Apply: • SE engine oil type 10W30 (on the tansmission box cover bearing) 2. Install: • secondary sheave axle (on transmission case cover) 3. Install: • circlip • oil seal NOTE: Apply grease with lithium soap based onto the oil seal lips.
ENGINE ASSEMBLY AND ADJUSTMENT STARTER SYSTEM Collar Shaft Starter wheel gear Flat washer Bearing Idle gear Starter clutch O-ring Plate Starter motor 8 Nm (0.8 m • kg) 13 Nm (1.3 m • kg) 4-29...
ENGINE ASSEMBLY AND ADJUSTMENT INSTALLING THE 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.
ENGINE ASSEMBLY AND ADJUSTMENT EAS00324 ASSEMBLING THE SECONDARY SHEAVE 1. Lubricate: • secondary fixed sheave’s inner surface • secondary sliding sheave’s inner surface Recommended lubricant assembly lube 2. Install: • secondary sliding sheave NOTE: Take care that the lips of the oil seals do not turn when the pulley wheel is installed.
ENGINE ASSEMBLY AND ADJUSTMENT 8. Adjust: • v-belt Tense the V-belt by turning the primary she- ave several times. 9. Install: • fan (CS50 only) Side right Screw (fan) 7 Nm (0.7 m • kg) INSTALLING THE KICKSTARTER 1. Install: •...
ENGINE ASSEMBLY AND ADJUSTMENT 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 •...
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5. Install: • thermostat (CS50Z only) on cylinder head 5 Nm (0.5 m • kg) • cylinder head • spark plug • air covers (CS50 only) NOTE: • The arrow “EX” from the cylinder head should point to the exhaust side.
ENGINE ASSEMBLY AND ADJUSTMENT 6. Install: • central stand • spring • axle • clasp • rubber washer • strap loop 7. Install: • brake shoes • flat washer • rear wheel • rear brake cable ENGINE REMOUNTING When the engine is being assembled, reverse the removal procedure.
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Rear wheel axle bolt 125 Nm (12.5 m • kg) 6. Install: • muffler • fan cover (CS50 only) Bolt (muffler) 26 Nm (2.6 m • kg) Bolt (exhaust pipe) 9 Nm (0.9 m • kg) • coolant hose (on water pump cover) (CS50Z only) Refill coolant and bleed the air.
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COOL CHAPTER 5 COOLING SYSTEM (CS50Z only) RADIATOR AND WATER PUMP ………………………………………………5-1 REMOVING THE RADIATOR …………………………………………………5-2 REMOVING THE WATER PUMP ……………………………………………5-2 CHECKING THE RADIATOR …………………………………………………5-3 CHECKING THE WATER PUMP ……………………………………………5-3 INSTALLING THE WATER PUMP ……………………………………………5-4 INSTALLING THE RADIATOR…………………………………………………5-5 THERMOSTAT ……………………………………………………………………5-5 REMOVING THE THERMOSTAT ……………………………………………5-5 CHECKING THE THERMOSTAT ……………………………………………5-6 INSTALLING THE THERMOSTAT ……………………………………………5-6...
COOL RADIATOR AND WATER PUMP EAS00454 COOLING SYSTEM (CS50Z only) RADIATOR AND WATER PUMP Radiator Water pump outlet hose Radiator inlet hose O-ring Radiator outlet hose Reservoir tank Carburetor inlet hose Reservoir tank hose Carburetor outlet hose Thermostatic valve Impeller Thermo switch Water pump cover 9 Nm (0.9 m •...
COOL RADIATOR AND WATER PUMP REMOVING THE RADIATOR 1. Remove: • front upper cowling • front middle cowling • front lower cowling Refer to “FRONT COWLING AND FOO- TREST” in chapter 3. 2. Drain: • coolant (from cooling system) Refer to “CHANGING THE COOLANT” in chapter 3.
COOL RADIATOR AND WATER PUMP EAS00455 CHECKING THE RADIATOR 1. Check: • radiator fins Obstruction Clean. Apply compressed air to the rear of the radiator. Damage Repair or replace. NOTE: Straighten any flattened fins with a thin, flathe- ad screwdriver. 2.
COOL RADIATOR AND WATER PUMP EAS00477 INSTALLING THE WATER PUMP NOTE: Always replace the entire water pump assembly. 1. Install: • impeller • pin • water pump drive pulley • circlip NOTE: After installation, check that the impeller shaft rotates smoothly. 2.
COOL RADIATOR AND WATER PUMP / THERMOSTAT EAS00456 INSTALLING THE RADIATOR 1. Install: • hose clamp NOTE: Install the hose clamp with a pliers 2. Fill: • cooling system (with the specified amount of the recom- mended coolant) Refer to “CHANGING THE COOLANT” in chapter 3.
COOL THERMOSTAT EAS00462 CHECKING THE THERMOSTAT 1. Check: • thermostat Does not open at 70.0°C ~ 82.0°C Replace. a. Suspend the thermostat in a container filled with water. b. Slowly heat the water. c. Place a thermometer in the water. d.
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.
CARB REED VALVE 2. Measure: • valve stopper height Out of specification Adjust the stop- per/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.
CHAS CHAPTER 7 CHASSIS FRONT WHEEL …………………………………………………………………7-1 REMOVING THE FRONT WHEEL ……………………………………………7-2 CHECKING THE FRONT WHEEL ……………………………………………7-3 CHECKING HE SPEED SENSOR UNIT ……………………………………7-4 CHECKING THE BRAKE DISC ………………………………………………7-4 INSTALLING THE FRONT WHEEL …………………………………………7-6 FRONT BRAKE……………………………………………………………………7-7 REPLACING THE FRONT BRAKE PADS……………………………………7-8 REMOVING THE BRAKE HOSE ……………………………………………7-10 CHECKING THE BRAKE HOSE ……………………………………………7-10 INSTALLING THE BRAKE HOSE …………………………………………7-11...
CHAS FRONT WHEEL EAS00518 CHASSIS FRONT WHEEL Wheel axle Tyre Speed sensor unit Front rim Bearing Oil seal Collar Spacer Valve Tyre: Size: 110/70-12 Type: 47 L Rim runout limit: Vertical: 1.0 mm Lateral: 1.0 mm Wheel axle bend limit: 0.25 mm 47.5 Nm (4.75 m •...
CHAS FRONT WHEEL EAS00520 REMOVING THE FRONT WHEEL 1. Stand the scooter on a level surface. s WARNING Securely support the scooter so that there is no danger of it falling over. NOTE: Place the scooter on a suitable stand so that the front wheel is elevated.
CHAS FRONT WHEEL EAS00525 CHECKING THE FRONT WHEEL 1. Check: • wheel axle Roll the wheel axle on a flat surface. Bends Replace. s WARNING Do not attempt to straighten a bent wheel axle. 2. Check: • tire • front wheel Damage/wear Replace.
CHAS FRONT WHEEL CAUTION: Do not contact the wheel bearing inner race or balls . Contact should be made only with the outer race NOTE: Use a socket that matches the diameter of the wheel bearing outer race and oil seal. EAS00535 CHECKING THE SPEED SENSOR UNIT 1.
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CHAS FRONT WHEEL 3. Measure: • brake disc thickness Measure the brake disc thickness at a few different locations. Out of specification Replace. Brake disc thickness limit (mini- mum) 3.0 mm 4. Adjust: • brake disc deflection a. Remove the brake disc. b.
CHAS FRONT WHEEL EAS00542 INSTALLING THE FRONT WHEEL 1. Lubricate: • wheel axle • wheel bearings • oil seal lips • speedometer drive gear • speedometer driven gear Recommended lubricant Lithium-soap-based grease 2. Install: • speed sensor unit NOTE: Make sure the speed sensor unit and the wheel hub are installed with the two projec- tions engaged into the flat surface of the wheel.
CHAS FRONT BRAKE EAS00576 FRONT BRAKE Retaining bolt Master cylinder cap Air bleed screw Diaphragm Caliper assembly Brake hose Pad spring Brake pump assy Pad set Front brake lever Retaining pin Copper washers Brake pad cover Union bolt Brake disc Brake light switch cable Type of brake fluid: DOT #4...
CHAS FRONT BRAKE 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 •...
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CHAS FRONT BRAKE NOTE: The triangle mark k a on the brake pad shim must point in the direction of disc rotation. e. Install new brake pads and a new brake pad spring NOTE: The arrow mark k b of the brake pad spring must point in the direction of disc rotation.
CHAS FRONT BRAKE REMOVING THE BRAKE HOSE NOTE: Before replacing the brake hose, drain the brake fluid from the entire brake system. 1. Remove: • union bolt • copper washers • brake hose NOTE: To collect any remaining brake fluid, place a container under the end of the brake hose.
CHAS FRONT BRAKE EAS00596 INSTALLING THE BRAKE HOSE s WARNING • Never use solvents on internal brake components. Recommended brake fluid DOT #4 1. Install: • copper washers • brake hose • union bolt 23 Nm (2.3 m • kg) s WARNING Proper brake hose routing is essential to insure safe scooter operation.
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CHAS FRONT BRAKE s WARNING • Use only the designated brake fluid. Other brake fluids may cause the rubber seals to deteriorate, causing leakage and poor brake performance. • Refill with the same type of brake fluid that is already in the system. Mixing brake fluids may result in a harmful che- mical reaction, leading to poor brake performance.
CHAS REAR WHEEL Bolt (cam lever) 10 Nm (1.0 m • kg) 4. Install: • plain washer • brake cable EAS00574 INSTALLING THE REAR WHEEL When installing the rear wheel, reverse the removal procedure. The following points should be remembered. 1.
CHAS FRONT FORK EAS00646 FRONT FORK Steering bracket Spring Bolt Piston Rubber cap Rebound spring Circlip Circlip Spring stopper Inner tube O-ring Oil lock piece Collar Outer tube Dust seal Washer Oil seal circlip Bolt Oil seal Fork spring free lenght: 224 mm Fork oil capacity: 45 cc ±...
CHAS FRONT FORK EAS00651 REMOVING THE FRONT FORK LEGS 1. Place the scooter on its central stand and place an adequate support under the engi- 2. Remove: • brake calipers Refer to “FRONT BRAKE REMOVAL” sec- tion. 3. Remove: • front fender •...
CHAS FRONT FORK 4. Remove: • bolt (hydraulic rod) • copper washer NOTE: Remove the bolt (hydraulic rod) while the hydraulic rod is held with the T-handle a support T-handle: 90890-01326 Support: 90890-01294 5. Remove: • inner tube • piston (hydraulic rod) •...
CHAS FRONT FORK EAS00658 ASSEMBLING THE FRONT FORK LEGS 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 • Circlips • Ensure that all components are clean before assembly.
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CHAS FRONT FORK 3. Install: • circlip • dust seal NOTE: Couple the circlip correctly on the groove of the outer tube 4. Fill: • fork oil Quantity (each front fork leg) 45 cc Recommended oil SAE 10W or equivalent From fork leg oil level (from the top of the inner tube, with the inner tube fully compressed and...
CHAS FRONT FORK EAS00663 INSTALLING THE FRONT FORK LEGS Reverse the removal procedure. The following points should be remembered 1. Install: • front fork • circlip NOTE: Attach the circlip correctly on the inner tube groove. 2. Tighten: • pinch bolt (steering bracket): Pinch bolt (steering bracket) 30 Nm (3.0 m •...
CHAS HANDLEBAR AND STEERING EAS00666 REMOVING THE HANDLEBAR 1. Stand the scooter on a level surface. s WARNING Securely support the scooter so that there is no danger of it falling over. 2. Remove: • front upper cowling • front middle cowling •...
CHAS HANDLEBAR AND STEERING EAS00678 REMOVING THE LOWER BRACKET 1. Stand the scooter on a level surface. s WARNING Securely support the scooter so that there is no danger of it falling over. 2. Remove: • handlebar 3. Remove: • brake caliper •...
CHAS HANDLEBAR AND STEERING EAS00668 CHECKING THE HANDLEBAR 1. Check: • handlebar Bends/cracks/damage Replace. s WARNING Do not attempt to straighten a bent handle- bar as this may dangerously weaken it. 2. Install: • handlebar grip a. Apply a thin coat of rubber adhesive onto the left end of the handlebar.
CHAS HANDLEBAR AND STEERING EAS00673 INSTALLING THE HANDLEBAR 1. Stand the scooter on a level surface. s WARNING Securely support the scooter so that there is no danger of it falling over. 2. Install: • handlebar NOTE: Align the slot k a on the steering with the pin on the handlebar.
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ELEC CHAPTER 8 ELECTRICAL SYSTEM ELECTRICAL COMPONENTS …………………………………………………8-1 CHECKING SWITCH CONTINUITY……………………………………………8-3 CHECKING THE SWITCHES……………………………………………………8-4 CHECKING THE BULBS AND BULB SOCKETS ……………………………8-5 TYPS OF BULBS ………………………………………………………………8-5 CHECKING THE CONDITION OF THE BULBS ……………………………8-5 CHECKING THE CONDITION OF THE BULB SOCKETS…………………8-6 IGNITION SYSTEM ………………………………………………………………8-8 CIRCUIT DIAGRAM ……………………………………………………………8-8 TROUBLESHOOTING …………………………………………………………8-9 ELECTRIC STARTING SYSTEM………………………………………………8-12...
ELEC CHECKING SWITCH CONTINUTY EAS00730 CHECKING SWITCH CONTINUITY Check each switch for continuity with the poc- ket tester. If the continuity reading is incorrect, check the wiring connections and if necessary, replace the switch. CAUTION: Never insert the tester probes into the cou- pler terminal slots.
ELEC CHECKING THE SWITCHES EAS00731 CHECKING THE SWITCHES Check each switch for damage or wear, proper Damage/wear Repair or replace. connections, and also for continuity between the Improperly connected Properly connect. terminals. Refer to “CHECKING SWITCH CON- Incorrect continuity reading Replace the TINUITY”.
ELEC CHECKING THE BULBS AND BULB SOCKETS EAS00733 CHECKING THE BULBS AND BULB SOCKETS Check each bulb and bulb socket for damage or wear, proper connections, and also for con- tinuity between the terminals. Damage/wear Repair or replace the bulb, bulb socket or both.
ELEC CHECKING THE BULBS AND BULB SOCKETS • Avoid touching the glass part of the headlight bulb to keep it free from oil, otherwise the transparency of the glass, the life of the bulb, and the luminous flux will be adversely affected. If the head- light bulb gets soiled, thoroughly clean it with a cloth moistened with alcohol or lacquer thinner.
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ELEC CHECKING THE BULBS AND BULB SOCKETS b. Connect the pocket tester probes to the respective leads of the bulb socket. c. Check the bulb socket for continuity. If any of the readings indicate no continuity, repla- ce the bulb socket.
ELEC IGNITION SYSTEM EAS00740 EAS00736 TROUBLESHOOTING 1. Spark plug The ignition system fails to operate • Check the condition of the spark plug. (no spark or intermittent spark). • Check the spark plug type. • Measure the spark plug gap. Check: Refer to “CHECKING THE SPARK PLUG”...
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ELEC IGNITION SYSTEM EAS00744 • Connect the pocket tester (Ω x 1k) to the 3. Spark plug cap resistance ignition coil as shown. • Remove the spark plug cap from the spark plug lead. • Connect the pocket tester (“Ω x 1k” range) to the spark plug cap as shown.
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ELEC IGNITION SYSTEM EAS00748 EAS00739 6. Pickup coil resistance 8. Battery • Disconnect the pickup coil coupler from the • Check the condition of the battery. wire harness. Refer to “CHECKING AND CHARGING THE • Connect the pocket tester (Ω x 100) to the BATTERY”...
ELEC ELECTRIC STARTING SYSTEM EAS00755 ELECTRIC STARTING SYSTEM CIRCUIT DIAGRAM Main switch Starter relay Front brake switch Fuse Starter motor Rear brake switch Battery Start switch 8-12...
ELEC ELECTRIC STARTING SYSTEM EAS00756 STARTING CIRCUIT CUT-OFF SYSTEM LOCK OPERATION If the main switch is set to “ON” the starter OPEN motor can only operate if at least one of the following conditions is met: CHECK • The front brake switch is ON. •...
ELEC ELECTRIC STARTING SYSTEM EAS00757 EAS00739 TROUBLESHOOTING 2. Battery • Check the condition of the battery. The starter motor fails to turn. Refer to “CHECKING AND CHARGING THE Check: BATTERY” in chapter 3. 1. main fuse Minimum open-circuit voltage 2. battery 12.8 V or more at 20°C 3.
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ELEC ELECTRIC STARTING SYSTEM EAS00761 EAS00766 4. Starter relay 7. Wiring • Disconnect the starter relay coupler from • Check the entire starting system’s wiring. the coupler. Refer to “CIRCUIT DIAGRAM”. • Connect the pocket tester (Ω x 1) and bat- •...
ELEC ELECTRIC STARTING SYSTEM EAS00767 STARTER MOTOR O-ring Armature assembly Starter motor front cover Starter motor rear cover Rubber seal Wiring Brush holder / brushes Brush wear limit: 0.9 mm Commutator wear limit: 14.8 mm Mica lower cut-off: 1.15 mm 8-16...
ELEC ELECTRIC STARTING SYSTEM REMOVING THE STARTER MOTOR 1. Remove: • exhaust pipe assembly • rear wheel • starter motor EAS00769 CHECKING THE STARTER MOTOR 1. Check: • commutator Dirt Clean with 600-grit sandpaper. 2. Measure: • commutator diameter k a Out of specification Replace the starter motor.
ELEC ELECTRIC STARTING SYSTEM EAS00772 ASSEMBLING THE STARTER MOTOR 1. Install: • brush set • rubber seal • starter motor front cover 2. Install: • starter motor rear cover 3. Install: • Starter motor bolts 13 Nm (1.3 m • kg) NOTE: When install the starter motor the ground ter- minal k a is installed with upper side bolt.
ELEC CHARGING SYSTEM EAS00774 EAS00738 TROUBLESHOOTING 2. Main fuse The battery is not being charged. • Check the fuse for continuity. Refer to “CHECKING THE FUSES” in chap- Check: ter 3. • Is the fuse OK? 1. charging voltage 2. main fuse 3.
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ELEC CHARGING SYSTEM Positive tester probe white Negative tester probe black • Measure the charging coil resistance. Charging coil resistance 0.288 ~ 0.432 Ω at 20°C • Is the charging coil OK? Replace the char- ging coil assembly. EAS00779 5. Wiring •...
ELEC LIGHTING SYSTEM EAS00782 EAS00784 TROUBLESHOOTING 2. Dimmer switch • Check the dimmer switch for continuity. Any of the following fail to light: head- Refer to “CHECKING THE SWITCHES”. light, high beam indicator light, taillight, • Is the dimmer switch OK? position light, and meter light.
ELEC LIGHTING SYSTEM EAS00788 CHECKING THE LIGHTING SYSTEM Meter light coupler (wire harness side) • Set the main switch to “ON”. 1. The headlight and the high beam indicator • Start the engine. light fail to come on. • Set the dimmer switch to “HI” or “LO”. •...
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ELEC LIGHTING SYSTEM • Set the main switch to “ON”. • Set the main switch to “ON”. • Start the engine. • Start the engine. • Measure the voltage (DC 12 V) of blue • Measure the voltage (DC 12 V) of blue the meter light coupler (wire harness side).
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ELEC LIGHTING SYSTEM • Set the main switch to “ON”. • Start the engine. • Measure the voltage (DC 12 V) of blue the position light coupler (positionlight side). • Is the voltage within specification? This circuit is OK. Wiring circuit from the main switch to the position light coupler is faulty...
ELEC SIGNALING SYSTEM EAS00793 SIGNALING SYSTEM CIRCUIT DIAGRAM Main switch Fuse Battery Front brake switch Rear brake switch Tail/brake light Turn signal relay Turn signal switch Front turn signal light (left) Front turn signal light (right) Rear turn signal light (left) Rear turn signal light (right) Horn Horn switch...
ELEC SIGNALING SYSTEM EAS00794 EAS00749 TROUBLESHOOTING 3. Main switch •Any of the following fail to light: flasher • Check the main switch for continuity. light, brake light or an indicator light. Refer to “CHECKING THE SWITCHES”. •The horn fails to sound. •...
ELEC SIGNALING SYSTEM EAS00796 CHECKING THE SIGNALING SYSTEM 3. Horn 1. The horn fails to sound. • Disconnect the pink connector at the horn 1. Horn switch terminal. • Connect a jumper lead to the horn terminal • Check the horn switch for continuity. and ground the jumper lead.
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ELEC SIGNALING SYSTEM EAS00798 • Set the main switch to “ON”. 2. The tail/brake light fails to come on. • Pull in the brake levers. 1. Tail/brake light bulb and socket • Measure the voltage (DC 12 V) of green/yellow on the tail/brake light cou- •...
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ELEC SIGNALING SYSTEM 3. Voltage • Set the main switch to “ON”. • Set the turn signal switch to “L” or “R”. • Connect the pocket tester (DC 20 V) to the • Measure the voltage (DC 12 V) on turn signal relay coupler (wire harness side) brown/white at the turn signal relay cou-...
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ELEC SIGNALING SYSTEM • Set the main switch to “ON”. 3. Voltage • Set the turn signal switch to “L” or “R”. • Connect the pocket tester (DC 20 V) to the • Measure the voltage (DC 12 V) of the cho- meter coupler (wire harness side) as colate or dark green 2 at the turn signal...
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ELEC SIGNALING SYSTEM • Measure the fuel sender resistances. 3. Fuel level gauge • Set the main switch to “ON”. Fuel sender resistance (up position • Move the float up or down. “F”) • Check that the display segments of the fuel (Ω...
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ELEC SIGNALING SYSTEM EAS00802 • Set the main switch to “ON”. 7. The water temperature warning light fails to • Measure the voltage (DC 12 V) of red/yellow come on (CS50Z only). on the multi-function meter coupler (wire harness side). 1.
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ELEC SIGNALING SYSTEM s WARNING • Handle the thermo switch with special care. • Never subject the thermo switch to strong shocks. If the thermo switch is dropped, replace it. Thermo switch 16 Nm (1.6m • kg) ® Three bond sealock •...
TRBL STARTING FAILURE/HARD STARTING SHTG EAS00845 TROUBLESHOOTING NOTE: The following guide for troubleshooting does not cover all the possible causes of trouble. It should be helpful, however, as a guide to basic troubleshooting. Refer to the relative procedure in this manual for checks, adjustments, and replacement of parts.
TRBL FAULTY FRONT FORK LEGS / UNSTABLE HANDLING SHTG EAS00861 FAULTY FRONT FORK LEGS LEAKING OIL MALFUNCTION • Bent, damaged or rusty inner tube • Bent or damaged inner tube • Cracked or damaged outer tube • Bent or damaged outer tube •...
TRBL FAULTY LIGHTING OR SIGNALING SYSTEM SHTG EAS00866 FAULTY LIGHTING OR SIGNALING SYSTEM HEADLIGHT DOES NOT COME ON TURN SIGNAL BLINKS SLOWLY • Wrong headlight bulb • Faulty turn signal relay • Too many electrical accessories • Faulty main switch •...
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CS50/Z 2002 WIRING DIAGRAM COLOR CODE B.......BLACK 1. DC-CDI magneto R.......RED 2. DC-CDI. unit L........BLUE 3. Ignition coil G.......GREEN 4. Spark plug O.......ORANGE Y........YELLOW 5. Main switch P........PINK 6. Fuse Br......BROWN 7. Battery Ch......CHOCOLATE 8. Rectifier/regulator Sb.