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Home / How to Install Headlight Switch on Mio I 125

How to Install Headlight Switch on Mio I 125

  • Contents
  • Table of Contents
  • Troubleshooting
  • Bookmarks

Quick Links

  • 24

    2. Maintenance Information

  • 42

    3. Lubrication System

  • 50

    4. Fuel System

  • 62

    5. Removal & Installation of Engine

  • 70

    6. Cylinder Head / Valve

  • 88

    7. Cylinder / Piston

  • 96

    8. V-Belt Drive System / Kick Starter

  • 110

    9. Final Drive Mechanism

  • 118

    10. Alternator / Starting Clutch

  • 126

    11. Crankcase / Crankshaft

  • 134

    12. Body Cover

  • 150

    13. Brake

  • 164

    14. Steering / Front Wheel / Front Cushion

  • 176

    15. Rear Wheel / Rear Cushion

  • 180

    16. Electrical Equipment

    • 181

      Mechanism Diagram ··························16-1

    • 181

      Operational Precautions

    • 183

      Trouble Diagnosis

    • 184

      Charging System

FORWARD

CONTENTS

HOW TO USE THIS MANUAL

Mechanism Illustrations

Mio 50 / 100

SERVICE MANUAL

Chapters

  • 24

    2. Maintenance Information

  • 42

    3. Lubrication System

  • 50

    4. Fuel System

  • 62

    5. Removal & Installation of Engine

  • 70

    6. Cylinder Head / Valve

  • 88

    7. Cylinder / Piston

  • 96

    8. V-Belt Drive System / Kick Starter

  • 110

    9. Final Drive Mechanism

  • 118

    10. Alternator / Starting Clutch

  • 126

    11. Crankcase / Crankshaft

  • 134

    12. Body Cover

  • 150

    13. Brake

  • 164

    14. Steering / Front Wheel / Front Cushion

  • 176

    15. Rear Wheel / Rear Cushion

  • 180

    16. Electrical Equipment

    • 181

      Mechanism Diagram ··························16-1

    • 181

      Operational Precautions

    • 183

      Trouble Diagnosis

    • 184

      Charging System

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  Related Manuals for Sym Mio 50

  Summary of Contents for Sym Mio 50

  • Page 1: Service Manual

    FORWARD CONTENTS HOW TO USE THIS MANUAL Mechanism Illustrations Mio 50 / 100 SERVICE MANUAL...
  • Page 2 "Service Procedures", "Operation Key Points", and "Inspection Adjustment" so that provides technician with service guidelines. If the style and construction of the scooter, Mio 50 / 100, are different from that of the photos, pictures shown in this manual, the actual vehicle shall prevail.

  • Page 3: General Information

    How To Use This Manual This service manual describes basic information of different system parts and system inspection & service for SANYANG Mio 50 / 100 scooters. In addition, please refer to the manual contents in detailed for the model you serviced in inspection and adjustment.
  • Page 4 Homepage Contents Page Content Index 1-1 ~ 1-18 General Information 2-1 ~ 2-18 Service Maintenance Information 3-1 ~ 3-8 Lubrication System 4-1 ~ 4-12 Fuel System 5-1 ~ 5-8 Engine Removal 6-1 ~ 6-18 Cylinder Head/Valve 7-1 ~ 7-8 Cylinder/Piston 8-1 ~ 8-14 "V"...
  • Page 5 Home page Contents Mechanism Illustrations HU05U / HU10U / HU10W Oil gauge Fuel tank Front winker Fuel tank cap Battery / Fuse / C.D.I. unit Helmet hook Headlight Luggage box Luggage box lock Air cleaner Winker / Horn / Back mirror Hazard or Seat open switch Start / headlight switch...

  • Page 6: General Information

    Homepage Contents 1. General Information Symbols and Marks····························1-1 Torque Values ···································· 1-11 General Safety ····································1-2 Troubles Diagnosis···························· 1-13 Service Precautions ···························1-3 Lubrication Points ····························· 1-17 Specifications ·····································1-9 Symbols and Marks Symbols and marks are used in this manual to indicate what and where the special service are needed, in case supplemental information is procedures needed for these symbols and marks, explanations will be added to the text instead of using the symbols or marks.

  • Page 7: General Safety

    To this chapter contents 1. General Information General Safety Carbon monoxide Battery If you must run your engine, ensure the place is Caution well ventilated. Never run your engine in a closed ¡ E Battery emits explosive gases; flame is strictly area.

  • Page 8: Service Precautions

    To this chapter contents 1. General Information Service Precautions Always use with SANYANG genuine parts and Never bend or twist a control cable to prevent recommended oils. Using non-designed parts unsmooth control and premature worn out. for SANYANG ATV may damage the ATV. Rubber parts may become deteriorated when Special tools are designed for remove and old, and prone to be damaged by solvent and oil.
  • Page 9 To this chapter contents 1. General Information The length of bolts and screws for assemblies, Remove residues of the old gasket or sealant cover plates or boxes is different from one before reinstallation, grind with a grindstone if another, be sure they are correctly installed. In the contact surface has any damage.
  • Page 10 To this chapter contents 1. General Information Lubricate the rotation face with specified After service completed, make sure all lubricant on the lubrication points before connection points is secured. assembling. Battery positive (+) cable should be connected firstly. And the two posts of battery have to be greased after connected the cables.
  • Page 11 To this chapter contents 1. General Information When separating a connector, it locker has to Insert the terminal completely. be unlocked firstly. Then, conduct the service Check if the terminal is covered by the boot. operation. Do not let boot open facing up. Secure wires and wire harnesses to the frame Do not pull the wires as removing a connector with respective wire bands at the designated...
  • Page 12 To this chapter contents 1. General Information Do not let the wire harness contact with rotating, Protect wires or wire harnesses with electrical moving or vibrating components as routing the tape or tube if they contact a sharp edge or harness.
  • Page 13 To this chapter contents 1. General Information Do not let the wire harness been twisted as With sand paper to clean rust on connector installation. pins/terminals if found. And then conduct connection operation later. Clean rust Wire harnesses routed along the handlebar should not be pulled too tight or have excessive slack, be rubbed against or interfere with adjacent or surrounding parts in all steering...

  • Page 14: Specifications

    To this chapter contents 1. General Information Specifications MAKER SANYANG MODEL HU05U 1710 mm TELESCOPE Overall Length Front Suspension System 700 mm UNlT SWING Overall Width Rear 1005 mm 3.0-10 42J Overall Height Front Tire Specifications 1170 mm 90/90-10 50J Wheel Base Rear 31 kg...
  • Page 15 To this chapter contents 1. General Information Specifications MAKER SANYANG MODEL HU10U/W 1710 mm TELESCOPE Overall Length Front Suspension System 700 mm UNlT SWING Overall Width Rear 1020 mm 90/90-10 50J Overall Height Front Tire Specifications 1220 mm 90/90-10 50J Wheel Base Rear 32.5 kg...

  • Page 16: Torque Values

    To this chapter contents 1. General Information Torque Values The torque values listed in above table are for more important tighten torque values. Please see standard values for not listed in the table. Standard Torque Values for Reference Type Tighten Torque Type Tighten Torque 5 mm bolt¡...
  • Page 17 To this chapter contents 1. General Information Frame Torque Values Item Q'ty Thread Dia. (mm) Torque Value (Kg-m) Remarks Mounting bolt for steering 4.0~5.0 handlebar Mounting nut for steering rod 25.4 1.0~2.0 Cone seat for steering rod 25.4 0.2~0.3 Front wheel shaft nut 5.0~7.0 Rear wheel shaft nut 11.0~13.0...
  • Page 18 To this chapter contents 1. General Information Troubles Diagnosis A. Engine hard to start or can not be started Check and adjustment Fault condition Probable causes Loosen carburetor drain bolt to check if there is gasoline inside the carburetor 1. No fuel in fuel tank 2.
  • Page 19 To this chapter contents 1. General Information B. Engine run sluggish (Speed does not pick up, lack of power) Check and adjustment Fault condition Probable causes Try gradual acceleration and check engine speed 1. Air cleaner clogged 1. Poor fuel supply Engine speed can be Engine speed can not be 2.
  • Page 20 To this chapter contents 1. General Information C. Engine runs sluggish (especially in low speed and idling) Check and adjustment Fault condition Probable causes Check ignition timing (Using ignition lamp) Normal Abnormal 1. Incorrect ignition timing (malfunction of CDI or AC alternator) Adjust the air screw of carburetor Good...
  • Page 21 To this chapter contents 1. General Information E. Clutch, Driving And Driving Pulley FAULT CONDITIONS PROBABLE CAUSES 1. Driving belt worn out or deformation 2. Driving disk damaged Engine can be started but 3. Driving pulley spring broken motorcycle can not be moved. 4.

  • Page 22: Lubrication Points

    To this chapter contents 1. General Information Lubrication Points Acceleration cable/ Front & rear brake lever pivot Seat locker Steering shaft bearing Speedometer gear/ Side stand shaft Main stand shaft Clutch bearing front wheel bearing 1-17...
  • Page 23 To this chapter contents 1. General Information Note: 1-18...

  • Page 24: Table Of Contents

    Home page Contents 2. Maintenance Information Precautions in Operation...... 2-1 Cylinder Compression Pressure..2-9 Periodical Maintenance Schedule..2-2 Driving System ......... 2-9 Lubrication System ....... 2-3 Steering System ....... 2-10 Fuel System ........... 2-4 Suspension System ......2-10 Air Cleaner ..........2-5 Front Disk Brake System....

  • Page 25: Periodical Maintenance Schedule

    They are prohibited to be adjusted or repaired by unauthorized people. Otherwise, SYM is no responsible for the charge. 2. Clean or replace the air cleaner element more often when the motorcycle is operated on dusty roads or in the Heavily- polluted environment.

  • Page 26: Lubrication System

    To this chapter contents 2. Maintenance Information Lubrication System Engine Oil Capacity Caution The vehicle must be parked on a level ground when checking oil capacity. Run the engine for 2-3 minutes then stop, wait about 2-3 more minutes allowing engine oil to settle before checking the oil level.

  • Page 27: Fuel System

    To this chapter contents 2. Maintenance Information Gear Oil Oil refilling bolt Inspection Check gear oil if leaking. Park the motorcycle with main stand on flat level place. Turn off engine and remove the gear oil draining plug. Place a measurement cup under the draining hole. Check gear oil if enough.

  • Page 28: Air Cleaner

    To this chapter contents 2. Maintenance Information Air Cleaner Element Remove the air cleaner cover (7 screws) Remove element. Check the element if dirt or damaged. Replace it with new one if dirt or damaged. Throttle Valve Operation Have a wide open of throttle valve as handle bar in 2~6 mm any position and release it to let back original (full closed) position.

  • Page 29: Crankcase Blow-By Ventilation

    To this chapter contents 2. Maintenance Information Primary adjustment is conducted from cable button side. Loosen fixing nut, and adjust by turning the adjustment nut. Tighten the fixing nut, and check acceleration operation condition. Adjustment nut Crankcase Blow-By Ventilation Pull out the plug from draining hose to clean deposits Caution When always riding in rainy area or full...

  • Page 30: Carburetor Idle Speed Adjustment

    To this chapter contents 2. Maintenance Information Valve clearance inspection and adjustment Check & adjust valve clearance with feeler gauge after open the valve adjustment hole cap. Valve clearance: HU10U/W 0.12±0.02mm (IN/EX) HU05U IN: 0.05±0.02mm EX: 0.10±0.02mm Loosen fixing nut and turn the adjustment nut for adjustment.

  • Page 31: Ignition System

    To this chapter contents 2. Maintenance Information Ignition System "F" Mark Ignition Timing Caution C.D.I ignition system is set by manufacturer so it can not be adjusted Ignition timing check procedure is for checking whether CDI function is in normal or not.

  • Page 32: Cylinder Compression Pressure

    To this chapter contents 2. Maintenance Information Cylinder Compression Pressure Warn up engine and then turn off the engine. Remove the trunk and the central cover. Remove spark plug cap and spark plug Install compression gauge Full open the throttle valve, and rotate the engine by means of stepping the foot-starting lever Caution Rotate the engine until the reading in the...

  • Page 33: Steering System

    To this chapter contents 2. Maintenance Information Steering System Caution Check all wires and cables if they are interfered with the rotation of steering handle bar. Lift the front wheel out of ground. Turn handle from right to left alternative and check if turning is smoothly.

  • Page 34: Front Disk Brake System

    To this chapter contents 2. Maintenance Information Front Disk Brake System Brake System Hose Make sure the brake hoses for corrosion or leaking oil. Brake Fluid Check brake fluid level in the brake fluid reservoir. If the level is lower than the LOWER limit, add brake fluid to UPPER limit.
  • Page 35 To this chapter contents 2. Maintenance Information ADDED BRAKE FLUID Master cylinder cap Add brake fluid to UPPER limit lever. Recommended brake fluid: DOT3 or DOT4 WELL RUN brake fluid Caution Upper limit Never mix or use dirty brake fluid to prevent from damage brake system or reducing brake Brake fluid performance.

  • Page 36: Drum Brake System

    To this chapter contents 2. Maintenance Information Drum Brake System Front Brake Free Play: (Drum brake) Measure free play of rear brake level at the end of 10¡ ã 20mm the lever. Free play: 10~20mm Adjust the free play by turning the front brake adjustment nut if necessary.

  • Page 37: Wheel / Tire

    To this chapter contents 2. Maintenance Information BRAKE LAMP SWITCH Rear brake light The brake light switch lit up brake light as brake switch applied. Make sure that electrical starter can be operated only under brake applying. Wheel / Tire Check if the tire pressure of front &...

  • Page 38: Battery

    To this chapter contents 2. Maintenance Information Battery Battery Removal Open the seat cushion and then the battery cap. (2 screws) Battery cables removal: 1. At first, remove the negative "-" cable. 2. Then, remove the positive "+" cable 3. Remove the battery. If there is some rust on battery posts, clean it with steel brush.

  • Page 39: Special Service Tools Catalogue

    (ø28mm) (ø20mm) Puller/presser for crankcase Puller/presser for crankcase Name Name Name Valve spring compressor bushing bushing Parts no. SYM-1120310 Parts no. SYM-1120320 Parts no. SYM-1471110/20 Valve clearance adjustment Name Name Name Valve spring compressor Valve clearance adjuster wrench Parts no. SYM-1471100 Parts no.
  • Page 40 To this chapter contents 2. Maintenance Information Name Bearing remover (inner type) Name Bearing remover (outer type) Name clutch spring compressor Parts no. SYM-6204002 Parts no. SYM-6204001 Parts no. SYM-2301000 Name Clutch mounting nut wrench Name Universal fixer Name Alternator flywheel remover Parts no.
  • Page 41 To this chapter contents 2. Maintenance Information NOTE: 2-18...
  • Page 42 Home page Contents 3. Lubrication System Mechanism Illustrations ····················· 3-1 Cleaning Engine Oil Strainer··············· 3-4 Operational Precautions····················· 3-2 Oil Pump ··············································· 3-5 Trouble Diagnosis ······························· 3-2 Gear Oil ················································· 3-8 Engine OIL ··········································· 3-3 Mechanism Illustrations Rock Arm Forcedly lubrication Cam Shaft Scoop lubrication Inner passage...

  • Page 43: Operational Precautions

    Gear oil filling bolt 1.0~1.4kgf-m Oil pump connection screw 0.1~0.3kgf-m Special Service Tools Strainer cap wrench SYM-ALL12361 One way clutch socket SYM-9020100 Universal fixer SYM-2210100 Trouble Diagnosis Low engine oil level Dirty oil Oil leaking No oil change in periodical...

  • Page 44: Engine Oil

    To this chapter contents 3. Lubrication System Engine OIL Turn off engine, and park the motorcycle in flat surface with main stand. Check oil level with oil dipstick Do not screw the dipstick into engine as checking. If oil level is nearly low level, fill out recommended oil to upper level.

  • Page 45: Cleaning Engine Oil Strainer

    Replace with new one if found. Install the oil strainer and spring. Install the oil strainer cap and tighten it. Special Service Tools: Strainer cap wrench SYM-ALL12361 Torque value¡ G 1.3~1.7kgf-m Fill out oil to the oil filler (Oil viscosity SAE 10W-30)

  • Page 46: Oil Pump

    Remove the alternator (refer to chapter 10). Remove the engine right cover. Remove the one-way clutch and starting gear (1 nut) Special Service Tools: One way clutch socket SYM-9020100 Universal fixer SYM-2210100 One way clutch socket Make sure that the pump axle can be rotated freely.
  • Page 47 To this chapter contents 3. Lubrication System Oil Pump Inspection Check the clearance between oil pump body and outer rotor Limit¡ G below 0.12mm Check clearance between inner and outer rotors. Limit¡ G below 0.12mm Check clearance between rotor side face and pump body Limit¡...
  • Page 48 Oil pump drive gear Universal fixer Install the one-way clutch and starting gear (1nut) Install the engine right cover. Install the alternator (refer to chapter 10). Special Service Tools: One way clutch socket SYM-9020100 Universal fixer SYM-2210100 One way clutch socket...

  • Page 49: Gear Oil

    And then, tighten the bolt. Torque Value¡ G 1.0~1.4kgf-m ¡ ° Recommended to apply with SYM HYPOID GEAR OIL (SAE 85W-140) Start engine and run it for 2~3 minutes.
  • Page 50 Home page Contents 4. Fuel System Mechanism Illustration ......4-1 Idle Speed Adjustment ...... 4-8 Operational Precautions....4-2 Fuel Tank ..........4-9 Trouble Diagnosis ......4-3 Air Cleaner.......... 4-11 Carburetor...........4-4 Mechanism Illustration Fuel tank cap Fuel vapor separator Fuel unit Fuel tank Fuel hose Vacuum type fuel coke Vacuum hose Carburetor...

  • Page 51: Operational Precautions

    To this chapter contents 4. Fuel System Operational Precautions General Information Warning Gasoline is a low ignition point and explosive materials, so always work in a well-ventilated place and strictly prohibit flame when working with gasoline. Caution Do not bend or twist throttle valve cable. Damaged cable will make unstable drive ability. When disassembling fuel system parts, pay attention to O-ring position, replace with new one as re-assembly There is a drain screw in the float chamber for draining residual gasoline.

  • Page 52: Trouble Diagnosis

    To this chapter contents 4. Fuel System Trouble Diagnosis Poor engine start Late ignition timing No fuel in fuel tank Malfunction of ignition system Clogged fuel tube Malfunction of carburetor Too much fuel in cylinder No spark from spark plug (malfunction of ignition Power insufficiency and fuel consuming system) Fuel system clogged...

  • Page 53: Carburetor

    To this chapter contents 4. Fuel System Carburetor Air cleaner clamp Heat-isolator clamp Carburetor Removal Remove the luggage box and seat. Loosen the adjustment nut and fixing nut of throttle valve cable, and release the cable from carburetor. Remove fuel pipe, vacuum hose. Remove air cut-off valve hose Disconnect automatic by-starter connectors.
  • Page 54 To this chapter contents 4. Fuel System 2 screws Air Cut-off Valve Removal Removal the throttle cable seat (screws x 2) Remove the screws (screw x 2) of the air cut-off valve and its cover. Remove the spring and vacuum diaphragm. Check if the diaphragm for deterioration or crack.
  • Page 55 To this chapter contents 4. Fuel System AUTOMATIC BY-STARTER Inspection Turn off engine and waiting for over 10 minutes for cooling. Check resistance across the two terminals of the automatic by-starter. Resistance value: Max. 10£ [ (Measured after engine stopped for more than 10 minutes) Replace the automatic by-starter with a new one if resistance value exceeds standard.
  • Page 56 To this chapter contents 4. Fuel System FLOAT CHAMBER Disassembly Remove 4 mounting screws and then the float chamber cover. Remove the float pin and float valve. Checking Drain screw Check float needle valve and valve seat for drop difference damage, wear out, dirty or clogged. Caution Float valve In case of worn out or dirt, the float valve and...

  • Page 57: Idle Speed Adjustment

    To this chapter contents 4. Fuel System Air-fuel mixture Assembly Install main jet, fuel needle jet holder, nozzle, idle jet and air-fuel mixture adjustment screw. Caution Set the adjustment screw in according to number of turns noted before it was removed. Install the float valve, float, and float pin.

  • Page 58: Fuel Tank

    3 screws Turn fuel unit setting plate to the left, and then remove fuel unit. Special Service Tools: Universal fixer SYM-2210100 Check if the float and washer is damaged. Replace it with new ones if damaged. Caution Do not bend the float arm of fuel metering gauge.
  • Page 59 To this chapter contents 4. Fuel System Each side 2 bolts Fuel tank removal Remove the left and right side covers. Open seat. Remove the luggage box. Remove rear carrier. Remove the left and right body covers. Remove the pedal (please refer to chapter 12 for these components above.) Remove fuel unit coupler.

  • Page 60: Air Cleaner

    To this chapter contents 4. Fuel System Air Cleaner Removal the element of the air cleaner Remove the air cleaner cover (7 screws). 7 screws Remove air cleaner element. Installation Install the air cleaner in the reverse order of removal. 4-11...
  • Page 61 To this chapter contents 4. Fuel System Removal of Air Cleaner Open the seat. Remove the luggage box (chapter 12). Remove the left side cover (chapter 12). Loose the air cleaner adapting-pipe clamp. Remove the EEC, PCV, AI system hoses. Remove the mounting bolts of the air cleaner body.

  • Page 62: Engine Removal

    Home page Contents 5. Removal & Installation of Engine Mechanism Illustrations ····················· 5-1 Removal of Engine Bush····················· 5-6 Operational Precautions····················· 5-2 Engine Hanger······································ 5-7 Engine Removal ·································· 5-3 Installation of Engine··························· 5-8 Mechanism Illustrations 3.5~4.5kgf-m 4.5~5.5kgf-m 4.5~5.5kgf-m 2.4~3.0kgf-m 4.5~5.5kgf-m...

  • Page 63: Operational Precautions

    The following parts can be serviced with the engine installed on the frame. 1. Carburetor 2. Driving disk, driving belt, clutch, and transporting disk 3. Final reduction gear mechanism Specification Specification Item MIO 50 MIO 100 Replacement 700 c.c. 650 c.c. Engine Oil Capacity Disassemble 800 c.c.

  • Page 64: Engine Removal

    To this chapter contents 5. Removal & Installation of Engine Engine Removal Open the seat. Remove the luggage box (Bolt× 4, Nut×1). Remove battery cover. Remove the battery negative (-) cable. Remove the battery positive (+) cable. Remove right and left side covers (1 screw on each side.).
  • Page 65 To this chapter contents 5. Removal & Installation of Engine Remove the fuel line, vacuum hose, and throttle valve cable from the carburetor. Loose the strap screw of the air cleaner guide, and then the air cleaner guide. Remove the exhaust muffler (2 Bolts, 2 Nuts). 2 Nuts 2 Bolts Remove the air cleaner connection bolts (2 bolts).
  • Page 66 To this chapter contents 5. Removal & Installation of Engine Remove the rear cushion lower bolt (1 bolt). 1 bolt Remove the engine hanger nuts and bolts (engine Á ³ ® ê ×1 side), and then remove the engine. With a bracket to support the engine to prevent from it damage by falling down as removing the engine.

  • Page 67: Removal Of Engine Bush

    Place the detent section of the bush remover toward the bush, and drive both the pressing ring and bolt in to press the bush out. Special Service Tools: Crankcase bush remover/presser SYM-1120310 Crankcase bush remover/presser SYM-1120320 Pressing In Place the flat section of the remover toward the bush, and then drive the bush, pressing ring, and bolt in to install the bush.

  • Page 68: Engine Hanger

    To this chapter contents 5. Removal & Installation of Engine Engine Hanger Removal Remove the right side bolt of engine hanger. (1 bolt on each side) 1 bolt on each side Remove the engine hanger. Check if the engine hanger bush and cushion rubber for damage.

  • Page 69: Installation Of Engine

    To this chapter contents 5. Removal & Installation of Engine Installation of Engine Install the engine according to the reversing order of removal. Caution Note both feet and hands safety for squeezing as engine installation. Do not bent or squeeze each wires or hose. Route all cables and wires in accordance with the routine layout.
  • Page 70 Home page Contents 6. Cylinder Head / Valve Mechanism Illustrations ····················· 6-1 Cylinder Head Inspection ·················· 6-10 Operational Precautions····················· 6-2 Valve Seat Inspection and Service ··· 6-12 Troubleshooting ·································· 6-3 Cylinder Head Reassembly ··············· 6-14 Cylinder Head Removal ······················ 6-4 Cylinder Head Installation ·················...

  • Page 71: Operational Precautions

    0.7~1.1kgf-m (apply with oil on bolt thread & seat) Spark plug 1.0~1.4kgf-m Special service tools Valve reamer: 5.0mm Valve guide driver: 5.0mm Valve cover wrench SYM-ALL12361 Valve spring compressor SYM-1471100 0r Valve spring compressor/installer SYM-1471110/20 Valve clearance adjustment wrench SYM-9001200 or Valve clearance adjuster SYM-9001210...

  • Page 72: Troubleshooting

    To this chapter contents 6. Cylinder Head / Valve Troubleshooting Engine performance will be affected by troubles on engine top end. The troubles usually can be determinate or by performing cylinder compression test and judging the abnormal noise generated. Rough Idle Low compression pressure Low compression pressure 1.

  • Page 73: Cylinder Head Removal

    To this chapter contents 6. Cylinder Head / Valve Cylinder Head Removal 5 Screws Remove the right cooling shroud from the engine outer cover. (5 screws) Remove the left cooling shroud (1 bolt). 1 bolt Remove the crankcase blow-by system hose from the cylinder head.
  • Page 74 To this chapter contents 6. Cylinder Head / Valve Turn the flywheel in counter clockwise motion with 1 bolt T type wrench until the "Timing" mark on camshaft aligned with the mark on the cylinder head. Remove camshaft sprocket mounting bolt and remove the sprocket.

  • Page 75: Cylinder Head Disassembly (Hu05U)

    6. Cylinder Head / Valve Cylinder Head Disassembly (HU05U) Remove the valve cover from the cylinder head. Special Service Tool: Cylinder head wrench: SYM-ALL12361 Remove the camshaft stopper of the rocker arm Camshaft stopper shaft (1 bolt). With valve rocker arm puller to drive into the rocker arm shaft, and then remove the rocker arm shaft and the rocker arm.

  • Page 76: Cylinder Head Disassembly (Hu10U/W)

    Cylinder Head Disassembly (HU10U/W) Remove the valve cover from the cylinder head. Special Service Tool: Cylinder head wrench: SYM-ALL12361 Remove the camshaft stopper of the rocker arm © T © w ¾ × ª O shaft (1 bolt). With valve rocker arm puller to drive into the rocker arm shaft, and then remove the rocker arm shaft and the rocker arm.
  • Page 77 To this chapter contents 6. Cylinder Head / Valve Remove the camshaft. Camshaft Inspection Inspect cam lobe height for damaged. Service Limit: (Refer to page 2) Inspect the camshaft bearing for looseness or wear out. If any damaged, replace whole set of camshaft and bearing.

  • Page 78: Valve Disassembly

    To this chapter contents 6. Cylinder Head / Valve Valve Disassembly Remove the valves Special Service Tool: Valve remover/installer SYM-1471110/20 Caution Place a rag under the bottom of the combustion chamber as disassembling to prevent from valve stem deformation. Remove the valve spring retainer, valve springs Valve stem and valves.

  • Page 79: Cylinder Head Inspection

    To this chapter contents 6. Cylinder Head / Valve Cylinder Head Inspection Cylinder Head Check if spark plug and valve holes are crack. Measure cylinder head wrap age with a straightedge and flat feeler gauge. Service limit: 0.05mm Valve spring free length Measure the free length of intake and exhaust valve springs.
  • Page 80 To this chapter contents 6. Cylinder Head / Valve Caution If clearance between valve stem and valve guide exceeded service limit, check whether the new clearance that only replaces new valve guide is within service limit or not. If so, replace valve guide. Correct it with reamer after replacement.

  • Page 81: Valve Seat Inspection And Service

    To this chapter contents 6. Cylinder Head / Valve Valve Seat Inspection and Service Clean up all carbon deposits onto intake and exhaust valves. Apply with emery slightly onto valve contact face. Grind valve seat with a rubber hose or other manual grinding tool.
  • Page 82 To this chapter contents 6. Cylinder Head / Valve Use 60° cutter to cut a quarter lower parts out. Remove the cutter and check new valve seat. Old valve seat width 60° Use 45° cutter to grind the valve seat to specified width.

  • Page 83: Cylinder Head Reassembly

    Valve Install the valves with the valve remover/installer. Special Service Tool: Valve remover / installer SYM-1471110/20. Caution Place a rag under the bottom of the combustion chamber as disassembling to prevent from valve stem deformation.

  • Page 84: Cylinder Head Installation

    To this chapter contents 6. Cylinder Head / Valve Assembly the cylinder head. Caution The tangent of rocker shaft of intake valve should match with the bolt hole of camshaft mounting seat. Lock pins Cylinder Head Installation Install the lock pins and new cylinder head gasket onto the cylinder.

  • Page 85: Valve Clearance Adjustment

    Adjustment nut. Standard Value: (Refer to page 2) Special Service Tool: Valve clearance adjustment wrench SYM-9001200 or valve clearance adjuster SYM-9001210. Install the side cover of the cylinder head. (2 bolts) 2 bolts Install the left cooling shroud of the engine body 1 bolt outer cover.
  • Page 86 To this chapter contents 6. Cylinder Head / Valve Install the cooling shroud of the engine body outer 5 Screws cover. (5 bolts) Install the engine onto the frame. (Refer to chapter 5) 6-17...
  • Page 87 To this chapter contents 6. Cylinder Head / Valve Notes: 6-18...
  • Page 88 Home page Contents 7. Cylinder / Piston Mechanism Illustrations ····················· 7-1 Piston Removal ····································7-5 Operational Precautions····················· 7-2 Piston Ring Installation ·······················7-7 Trouble Diagnosis ······························· 7-2 Piston Installation ································7-8 Cylinder Removal ································ 7-3 Cylinder Installation·····························7-8 Mechanism Illustrations 0.8~1.2kgf-m...

  • Page 89: Operational Precautions

    To this chapter contents 7. Cylinder / Piston Operational Precautions General Information Both cylinder and piston service cannot be carried out when engine mounted on frame. Specification Unit: mm Model HU10U/W HU05U Item Standard Limit Standard Limit 49.995~50.015 50.500 37.015~36.995 37.500 ¡...

  • Page 90: Cylinder Removal

    To this chapter contents 7. Cylinder / Piston Cylinder Removal Remove cylinder head. (Refer to chapter 6) Remove cam chain plate. Cam chain plate Remove cylinder. Remove cylinder gasket and lock pins. Cover the holes of crankcase and cam chain with a piece of cloth.
  • Page 91 To this chapter contents 7. Cylinder / Piston Inspection Check if the inner diameter of cylinder is worn out Exhaust side Intake side or damaged. In the 3 positions (top, center and bottom) of cylinder, measure the X and Y direction values respective in the cylinder.

  • Page 92: Piston Removal

    To this chapter contents 7. Cylinder / Piston Piston Removal Plug crankcase opening with a cleaning cloth to prevent from piston pin snap ring or other parts falling into crankcase when disassembling. Hold another snap ring with pliers. Push out the piston pin from the side that not removed the snap ring.
  • Page 93 To this chapter contents 7. Cylinder / Piston Measure the outer diameter of piston pin. Service Limit: (Refer to page 2) Measure the inner diameter of connecting rod small end. Service Limit: (Refer to page 2) Measure the inner diameter of piston pin hole. Service Limit: (Refer to page 2) Calculate clearance between piston pin and its hole.

  • Page 94: Piston Ring Installation

    To this chapter contents 7. Cylinder / Piston Piston Ring Installation Clean up piston top, ring groove, and piston shirt. Install the piston ring onto piston carefully. Place the openings of piston ring as diagram shown below. Caution Do not damage piston and piston rings as installation. All marks on the piston rings must be forwarded to up side.

  • Page 95: Piston Installation

    To this chapter contents 7. Cylinder / Piston Piston Installation Install piston and piston pin, and place the IN marks on the piston top side forward to intake valve. Install new piston pin snap ring. Caution Do not let the opening of piston pin snap ring align with the opening piston ring.
  • Page 96 Home page Contents 8. V-Belt Drive System / Kick Starter Mechanism Illustrations ····················8-1 Kick Starter········································· 8-3 Operational Precautions····················8-2 Drive Belt ············································ 8-5 Trouble Diagnosis ······························8-2 Movable Drive Face ··························· 8-7 Left Crankcase Cover ························8-3 Clutch / Driven Pulley ························ 8-10 Mechanism Illustrations 5.0~6.0kgf-m 5.0~6.0kgf-m...

  • Page 97: Operational Precautions

    Torque value: Special Service Tools Movable drive face nut: 5.0~6.0kgf-m Clutch spring compressor SYM-2301000 Clutch outer nut: 5.0~6.0kgf-m Bearing puller (inner type) SYM-6204002 Driven pulley nut: 5.0~6.0kgf-m Clutch mounting nut wrench SYM-9020200 Universal fixture SYM-2210100 Trouble Diagnosis Insufficient horsepower or poor high...

  • Page 98: Left Crankcase Cover

    To this chapter contents 8. V-Belt Drive System / Kick Starter Left Crankcase Cover Left crankcase cover removal Remove body cover Remove air cleaner (2 bolts) 2 bolts Remove left crankcase cover (8 bolts). Installation of the left crankcase cover Install the left crankcase cover (8 bolts) Tighten the air cleaner (2 bolts) 8 bolts...
  • Page 99 To this chapter contents 8. V-Belt Drive System / Kick Starter Remove the inner plate inside of left crankcase cover. (6 screws) 6 screws Install kick starter arm, rotate the lever slightly and Return spring then remove driven gear and washer. Remove the kick starter arm, kick starter spindle, spindle bush and return spring as well as socket.

  • Page 100: Drive Belt

    Remove left crankcase cover Hold drive face with universal fixture, and remove nut and drive face. Special Service Tool: Universal fixture SYM-2210100 Universal fixture Hold the clutch outer with the universal fixture, and the remove the nut and the clutch outer.
  • Page 101 Install the clutch with universal fixture, and then Clutch outer tighten nut to specified torque value. Torque value: 5.0~6.0kgf-m Special Service Tool: Universal fixture SYM-2210100 Universal fixer Caution When install the drive belt, if there is a arrow mark, then the arrow mark must point to rotation motion.

  • Page 102: Movable Drive Face

    Remove left crankcase cover. Hold drive face with universal fixture, and then remove drive face nut. Remove drive face. Special Service Tool: Universal fixture SYM-2210100 Universal fixture Take out the drive belt from the drive face. Drive face boss Movable drive face Remove movable drive face set and drive face boss from crankshaft.
  • Page 103 To this chapter contents 8. V-Belt Drive System / Kick Starter Inspection Weight roller The operation of movable drive face is means of the weight roller to pressing on it with centrifuge force. And then the speed is changed by the ramp plate rotation.
  • Page 104 To this chapter contents 8. V-Belt Drive System / Kick Starter Apply with some grease to inside of drive face Drive face surface boss hole, and install drive face boss. Caution The drive face surface has to be free of grease.

  • Page 105: Clutch / Driven Pulley

    Release the clutch spring compressor and remove clutch and spring from driven pulley. Special Service Tool: Clutch spring compressor SYM-2301000 Clutch mounting nut wrench SYM-9020200 Remove oil seal collar from driven pulley. Oil seal collar Remove guide pin, guide pin roller, and sliding Sliding driven face Guide pin driven face, and then remove O-ring &...
  • Page 106 To this chapter contents 8. V-Belt Drive System / Kick Starter Clutch lining Measure each clutch lining thickness. Replace it Clutch lining if exceeds service limit. Service limit: 2.0mm Clutch Driven pulley spring Measure the length of driven pulley spring. Replace it if exceeds service limit Service limit: HU01U/W...
  • Page 107 To this chapter contents 8. V-Belt Drive System / Kick Starter Clutch Block Replacement Drive plate Remove snap and washer, and the remove clutch Spring block and spring from driving plate. Check if spring is damage or insufficient elasticity. Snap ring Clutch block Check if shock absorption rubber is damage or Shock absorption...
  • Page 108 To this chapter contents 8. V-Belt Drive System / Kick Starter Install snap ring and mounting plate onto setting pin. Snap ring Replacement of Driven Pulley Bearing Remove inner bearing. Outer bearing Caution Oil seal If the inner bearing equipped with oil seal on one side in the driven pulley, then remove the oil seal firstly.
  • Page 109 To this chapter contents 8. V-Belt Drive System / Kick Starter Installation of Clutch / Driven Pulley Oil seal Assembly Install new oil seal and O-ring onto sliding driven face. Apply with specified grease to lubricate the inside of sliding driven face. Specified grease O-ring...

  • Page 110: Final Drive Mechanism

    Home page Contents 9. Final Drive Mechanism Mechanism Illustrations ····················· 9-1 Inspection of Final Drive Mechanism ··· 9-4 Operational Precautions····················· 9-2 Bearing Replacement ···························· 9-5 Trouble Diagnosis ······························· 9-2 Re-assembly of Final Driven Mechanism ································································· 9-7 Disassembly of Final Drive Mechanism ······························································...

  • Page 111: Operational Precautions

    Gear box cover 2.0~2.4kgf-m Gear oil drain plug 1.0~1.4kgf-m Gear oil filling bolt 0.8~1.2kgf-m Special service tools Inner type bearing puller SYM-6204002 Outer type bearing puller SYM-6204001 Gear box oil seal installer SYM-9120200 Gear box bearing installer SYM-9125500 Bearing (6204) installer...
  • Page 112 To this chapter contents 9. Final Drive Mechanism Disassembly of Final Drive HU05U Mechanism HU05U Remove the rear wheel (refer to chapter 15). Remove the clutch. Drain gear oil out from gear box. Remove gear box cover and then remove the cover and the drive shaft.

  • Page 113: Inspection Of Final Drive Mechanism

    To this chapter contents 9. Final Drive Mechanism Inspection of Final Drive Mechanism Check if the countershaft and the gear are worn out or damage. Check if the final driven shaft and gear are wear out or damage. Check bearings on gear box and cover. Rotate each bearing's inner ring with fingers.

  • Page 114: Bearing Replacement

    Remove drive shaft bearing from left crankcase using following tools; Special Service Tool: Inner type bearing puller SYM-6204002 Install new drive shaft bearing into left crankcase. Special Service Tool: Bearing (6204) installer...
  • Page 115 Then, install the drive shaft. Special Service Tool: Bearing (6204) installer SYM-9110400 Install the drive shaft. Special Service Tool: Drive shaft puller SYM-1130010 Puller set SYM-1130000-L Install new oil seal with the special service tool. Special Service Tool: Oil seal (20x32x6) installer SYM-9120200...

  • Page 116: Re-Assembly Of Final Driven Mechanism

    To this chapter contents 9. Final Drive Mechanism Re-assembly of Final Driven Dowel pin Mechanism HU05U Apply with grease onto the oil seal lip of final driven shaft. Final driven Install final driven shaft and final driven gear, shaft / Gear countershaft, and countershaft gear.
  • Page 117 Install the driven pulley / clutch outer / belt / movable drive face / drive face. Install the left crankshaft cover and kick starter. Install the rear wheel. Add gear oil. ¡ ° Recommended usage: SYM HYPOID GEAR OIL (SAE 85W-140)

  • Page 118: Alternator

    Home page Contents 10. Alternator / Starting Clutch Mechanism Illustrations ····················· 10-1 Starting Clutch ····································· 10-5 Operational Precautions····················· 10-2 Right Crankcase Cover Installation···· 10-7 Alternator Removal ····························· 10-3 Alternator Coil Set Installation············ 10-8 Right Crankcase Cover Removal ······· 10-4 Flywheel Installation···························· 10-8 Mechanism Illustrations 5.0~6.0kgf-m 9.0~10.0kgf-m...

  • Page 119: Operational Precautions

    Oil screen cover 1.3~1.7kgf-m Starting clutch hex mounting nut 9.0~10.0kgf-m with oil on the thread Starting clutch hex socket bolt 1.0~1.4kgf-m with adhesive Special service tools Flywheel puller SYM-3110A01 Universal fixture SYM-2210100 Anti-loosen mounting nut socket of starter gear SYM-A12590201 10-2...

  • Page 120: Alternator Removal

    Remove the fan shroud (2 screws, 2 bolts). 2 Bolts 2 Bolts Remove the cooling fan (4 bolts). Cooling fan Hold the flywheel with the universal fixture. Universal fixture Remove the 10mm nut on the flywheel. Special Service Tools: Universal Fixture SYM-2210100 10-3...

  • Page 121: Right Crankcase Cover Removal

    To this chapter contents 10. Alternator / Starting Clutch Remove the flywheel with the flywheel puller. Special service tools: Flywheel puller SYM-3110000 Caution Install a shaft protector on the right end of crankshaft to avoid damaging the crankshaft before installing the flywheel puller.

  • Page 122: Starting Clutch

    Hold the starting driven gear with the universal fixture. Remove the 22mm anti-loosen mounting nut and Mounting nut gasket. Special service tools: Nut puller of starter gear SYM-9020100 Universal fixture SYM-2210100 Caution The mounting nut is left-turn thread. Mounting nut socket Remove the starting driven gear.
  • Page 123 To this chapter contents 10. Alternator / Starting Clutch Check the starting driven gear for wear or damage. Measure the ID of the starting driven gear. Service Limit: ID: 32.06 mm or less Check the starting idle gear and shaft for wear or damage.

  • Page 124: Right Crankcase Cover Installation

    Caution Add engine oil onto the thread of mounting nut. Special service tools: Anti-loosen mounting nut socket of starter gear SYM-A12590201 Universal fixture SYM-2210100 Torque value: 9.0~10.0kgf-m Right Crankcase Cover Installation 9 bolts Install dowel pin and new gasket on the crankcase.

  • Page 125: Alternator Coil Set Installation

    Hold the flywheel with flywheel holder, and tighten its nut. Torque value: 5.0~6.0kgf-m Special service tool: Universal fixture SYM-2210100 Install the cooling fan (4 bolts). Install the cooling fan shroud (2 screws, 2 bolts) Install the exhaust pipe (2 bolts, 2 nuts) Install the right side cover.
  • Page 126 Home page Contents 11. Crankcase / Crankshaft Mechanism Illustrations ····················11-1 Disassembly of Crankcase·················· 11-3 Operational Precautions····················11-2 Crankshaft Inspection ························· 11-5 Trouble Diagnosis ······························11-2 Assembly of Crankcase······················· 11-6 Mechanism Illustrations 1.5~2.0kgf-m 1.0~1.4kgf-m 0.7~1.0kgf-m 0.8~1.2kgf-m 0.8~1.2kgf-m 3.5~4.5kgf-m 11-1...

  • Page 127: Operational Precautions

    Engine oil draining plug 3.5 ~ 4.5kgf-m Bolts for cam chain tensioner 0.8 ~ 1.2kgf-m Special Service Tools Oil seal (25X37X6) pressing tools SYM-9121600 Trouble Diagnosis Engine noise Loose crankshaft bearing Loose crankshaft pin bearing Wear piston pin or piston pin hole...

  • Page 128: Disassembly Of Crankcase

    To this chapter contents 11. Crankcase / Crankshaft Disassembly of Crankcase Á ³ ® ê ×2 Remove the cam chain tensioner (hex socket bolt) from the left side of crankcase. Remove the connection bolts (2 bolts) of the right-side crankcase. Remove the right-side crankcase.
  • Page 129 To this chapter contents 11. Crankcase / Crankshaft Remove the oil seal of left-side crankcase. 11-4...

  • Page 130: Crankshaft Inspection

    To this chapter contents 11. Crankcase / Crankshaft Crankshaft Inspection Measure left and right clearance of connecting rod big end. Service limit: Replace when it is more than 0.55 mm. Measure the radical clearance of the big end at the vertical directions. Service limit: Replace when it is more than 0.05 mm.

  • Page 131: Assembly Of Crankcase

    To this chapter contents 11. Crankcase / Crankshaft Assembly of Crankcase Install cam chain into the chain hole of the left crankcase, and then split out the cam chain. Caution Do not damage the cam chain as installing the crankshaft. Install crankshaft into the left crankcase and then install two and new crankcase gasket.
  • Page 132 Apply with some grease onto the oil seal lip and then install it onto the left crankcase. Oil seal installer Press-fit the oil seal to specified position with the oil seal installer (25x37x6) Special service tools: Oil seal installer (25x37x6) SYM-9120200 11-7...
  • Page 133 To this chapter contents 11. Crankcase / Crankshaft Notes: 11-8...
  • Page 134 Home page Contents 12. Body Cover Mechanism Illustrations ····················12-1 Battery Cover ····································· 12-10 Maintenance Information ···················12-2 Side Cover ·········································· 12-11 Front Cover ·········································12-3 Rear Center Cover ····························· 12-11 Handle Cover ······································12-4 Center Cover ······································ 12-12 Front Fender ·······································12-6 Body Cover········································· 12-13 Front under Spoiler ····························12-7 Floor Panel ·········································...

  • Page 135: Maintenance Information

    To this chapter contents 12. Body Cover Maintenance Information Body covers disassemble sequence: Handle front cover Front cover Handle rear cover Front under spoiler Front fender Front inner cover Luggage box & seat Rear mudguard Right/left side cover Center cover Under cover Battery cover Rear carrier...

  • Page 136: Front Cover

    To this chapter contents 12. Body Cover Front Cover Removal Remove the mounting screws (2 screws) of front cover from the front inner cover side. 2 Screws Remove the front mounting screw (1 screw) of the front cover. Push the front cover upward and then pull it forward so that the lower mounting groove of front cover can be separated from the front under spoiler.

  • Page 137: Handle Cover

    To this chapter contents 12. Body Cover Handle Cover Removal Loosen the handle front cover mounting screws (2 screws) of the handle from the handle rear cover. Push the two side screws, then hooks of handle two sides so that the handle covers can be separated.
  • Page 138 To this chapter contents 12. Body Cover Remove the speedometer cable. Disconnect the instrument panel and switch wiring couplers. Couplers Remove the handle rear cover rear side screw (1 screw). 1 screw Remove meter mounting bolts (2 bolts). Remove handle rear cover and meter. Installation Install according to the reverse procedure of removal.

  • Page 139: Front Fender

    To this chapter contents 12. Body Cover Front Fender Remove speedometer cable (1 screw). Remove front brake cable (drum brake type). Remove front brake caliper (disk brake type). Speedometer cable Front brake cable Remove the front wheel. (1 nut) 1 nut Remove the inner-up bolts (2 bolts) from the front 2 bolt fender.

  • Page 140: Front Under Spoiler

    To this chapter contents 12. Body Cover Front under Spoiler 10 screws Remove front cover. Remove the 10 screws on left & right both sides of rear-end from the inner cover. 2 screws Remove the front-upper screws, bolts. (2 screws & 2 bolts) 2 bolts Disconnect the winker light couplers.

  • Page 141: Front Inner Cover

    To this chapter contents 12. Body Cover Front Inner Cover 1 screw Removal Remove the front cover and the front under spoiler. Remove the main switch cap. (1 screw) Remove the rear mounting screw (1 screw) of the inner cover. 1 screw Winker relay Remove winker relay and meter control unit.

  • Page 142: Luggage Box

    To this chapter contents 12. Body Cover Luggage Box 4 Bolts Remove the mounting bolts (4 bolts) from the luggage box. Disconnect the engine start control switch coupler. Start control switch coupler Remove luggage box. Installation Install according to the reverse procedure of removal.

  • Page 143: Rear Carrier

    To this chapter contents 12. Body Cover Rear Carrier Remove the rear carrier mounting bolts and nuts (2 bolts & 2 nuts) 2 nuts 2 bolts Remove rear carrier. Installation Install according to the reverse procedure of removal. Battery Cover Remove batter cover screws (2 screws).

  • Page 144: Side Cover

    To this chapter contents 12. Body Cover Side Cover Removal Remove the 2 screws on both left & right sides covers. 1 screw on each side Remove right and left side covers. Installation Install according to the reverse procedure of removal.

  • Page 145: Center Cover

    To this chapter contents 12. Body Cover Center Cover Removal Remove center cover upper screw. (1 screw) 1 screw Remove center cover right and left screws. (2 screws) 1 screw on each side Remove center cover. Installation Install according to the reverse procedure of removal.
  • Page 146 To this chapter contents 12. Body Cover Body Cover Removal Remove the right and left side covers (2 screws). Remove the luggage box (4 bolts). Remove the rear carrier (2 bolts & 2 nuts). Remove the body cover two side screws. (1 screw on each side) 1 screw on each side Remove the body cover rear side screws.

  • Page 147: Floor Panel

    To this chapter contents 12. Body Cover Floor Panel 4 plugs Removal Remove the center cover, side covers, luggage box and body cover as well as body cover. Remove the 4 floor panel plugs. There are 4 floor panel mounting bolts. Remove battery cover, and then remove battery.

  • Page 148: Rear Fender

    To this chapter contents 12. Body Cover Rear Fender 2 bolts Remove the rear fender rear bolts (2 bolts). Remove the 2 bolts on the two sides. (1 bolts on 1 bolt on each side each side). Remove rear fender. Installation Install according to the reverse procedure of removal.

  • Page 149: Rear Mudguard

    To this chapter contents 12. Body Cover Rear Mudguard Remove the rear mudguard right side bolt (1 bolt). Loosen air cleaner mounting bolts, and then remove the rear mudguard left side bolts (2 bolts). 3 bolts Remove the rear mudguard. Installation Install according to the reverse procedure of removal.
  • Page 150 Home page Contents 13. Brake Mechanism Diagram-Front Disc Brake Brake Fluid Replacement / Air-Bleed · 13-7 System ················································· 13-1 Brake Caliper········································ 13-8 Mechanism Diagram-Front Drum Brake Brake Disc ············································ 13-9 System ················································· 13-2 Brake Master Cylinder ························· 13-9 Mechanism Diagram-Rear Drum Brake Drum Brake System ·····························...
  • Page 151 To this chapter contents 13. Brake Mechanism Diagram-Front Drum Brake System 0.8~1.2kgf-m 2.8~3.2kgf-m 5.0~7.0kgf-m 13-2...
  • Page 152 To this chapter contents 13. Brake Mechanism Diagram-Rear Drum Brake System 0.8~1.2kgf-m 2.8~3.2kgf-m 0.8~1.2kgf-m 11.0~13.0kgf-m 13-3...

  • Page 153: System

    To this chapter contents 13. Brake Operational Precautions General information Caution Inhaling asbestos may cause disorders of respiration system or cancer, therefore, never use air hose ● or dry brush to clean brake parts. Use vacuum cleaner or other authorized tool instead. The brake caliper can be removed without removing the hydraulic system.

  • Page 154: Trouble Diagnosis

    To this chapter contents 13. Brake Trouble Diagnosis Disc Brake Soft brake lever Uneven brake 1. Air inside the hydraulic system 1. Dirty brake lining/disc 2. Hydraulic system leaking 2. Poor wheel alignment 3. Worn master piston 3. Clogged brake hose 4.

  • Page 155: Hydraulic Brake System Inspection

    To this chapter contents 13. Brake Hydraulic Brake System Inspection Inspection of Hydraulic Brake System Hose connection Inspection Visual inspect for brake fluid leaking or damage. Check if brake hose connections loosen with wrench and turn the handlebar from right to left motion or press down the shock absorber to check if there is something is interfered with the brake system or brake components.

  • Page 156: Brake Fluid Replacement / Air-Bleed

    To this chapter contents 13. Brake Remove the master cylinder cap and diaphragm. Add good quality brake fluid and it has to add Master cylinder cap same brand brake fluid into the master cylinder. Clean dirty brake disc. Diaphragm Caution The dirty brake lining or disc will reduce the ●...

  • Page 157: Brake Caliper

    To this chapter contents 13. Brake Brake Caliper Removal Hose bolt Place a container under the brake caliper, and 2 Bolts loosen the brake hose bolt and finally remove the brake hoses. Caution Do not spill brake fluid on painted surfaces. ●...

  • Page 158: Brake Disc

    To this chapter contents 13. Brake Brake Disc Brake disc Inspection Visually check the brake disc for wear or break. Measure the thickness of the disc at several places. Replace the disc if it has exceeded the service limit. Allowable limit: 2.0 mm Micrometer Remove the brake disc from wheel.
  • Page 159 To this chapter contents 13. Brake Inspection Check the master cylinder for damage or scratch. Master cylinder Replace it if necessary. Measure the cylinder inner diameter at several points along both X and Y directions. Replace the cylinder if the measured values exceed allowable limit.
  • Page 160 To this chapter contents 13. Brake Installation Mounting seat Place the master cylinder onto handlebar, and Split ring install the split ring and bolts. The "UP" mark on the split ring should face upward. Align the split ring on the master cylinder seat with the alignment point on the handlebar.

  • Page 161: Drum Brake System

    To this chapter contents 13. Brake Drum Brake System Brake Drum Removal Use a vacuum cleaner and other suitable tools to clean the brake parts to minimize the hazard caused by the asbestos dust. Caution Inhaling asbestos dust may cause respiration ●...

  • Page 162: Brake Panel

    To this chapter contents 13. Brake Removal Front Brake cam Caution Brake linings must be replaced as a set. ● Remove brake shoes from the brake panel by pulling out the brake linings. Installation Apply a thin coat of grease to the brake cam and the anchor pin.
  • Page 163 To this chapter contents 13. Brake Installation Return spring Front Front brake panel Wear indicator Apply a thin cost of grease onto the brake cam shaft. Install the brake cam. Apply a thin cost of grease onto the oil seal lip and Brake cam then install the oil seal onto the brake cam shaft.

  • Page 164: Steering / Front Wheel / Front Cushion

    Home page Contents 14. Steering / Front Wheel / Front Cushion Mechanism Diagram ··························14-1 Front Wheel ········································ 14-5 Operational Precautions····················14-2 Front Cushion ···································· 14-10 Trouble diagnosis ······························14-2 Front Fork / Steering Column ··········· 14-10 Steering Handle ··································14-3 Mechanism Diagram 1.0~2.0kgf-m 4.0~5.0kgf-m 0.2~0.3kgf-m 2.4~3.0kgf-m...

  • Page 165: Operational Precautions

    2.4~3.0kgf-m Front brake caliper bolt 3.1~3.5kgf-m Special service tools Steering column wrench Bearing remover Inner type bearing remover SYM-6204002 Attachment, 32×35 mm Attachment, 42×47 mm Steering column nut wrench Steering column top cone ring nut wrench Trouble diagnosis Hard steering stem...

  • Page 166: Steering Handle

    To this chapter contents 14. Steering / Front Wheel / Front Cushion Steering Handle Handle switch screw Brake lever screw Removal Remove handle front & rear covers, meter and the front cover (refer to chapter 12). Drum Brake Type Remove the rear brake lever bolt & nut, and then remove the front brake cable.
  • Page 167 To this chapter contents 14. Steering / Front Wheel / Front Cushion Disc Brake Type Split ring 2 bolts Remove the 2 bolts of the brake master cylinder, and then take out the master cylinder and the split ring. Caution Do not operate the front brake lever to avoid to pressing out the brake lining when removing the master cylinder.

  • Page 168: Front Wheel

    To this chapter contents 14. Steering / Front Wheel / Front Cushion Front Wheel Removal Disc Brake Support body bottom and lift front wheel free of ground with a stand. Remove the screw, and disconnect speedometer cable from the gear box. Screw Remove the wheel axle nut and pull out the axle.
  • Page 169 Remove the dust seal on the right side of speedometer gear. Remove the bearing with the inner type bearing Bearing spacer remover. Take out the bearing spacer and then remove the Dust seal Bearing other bearing. Tool: Inner type bearing remover SYM-6204002 Bearing Wheel side collar 14-6...
  • Page 170 Remove the bearing with the inner type bearing remover. Take out the bearing spacer and then remove the other bearing. Tool: Inner type bearing remover SYM-6204002 Bearing Inspection Turn the inner race of bearing with fingers. The bearing should be turn smoothly. Also check if the Clearance outer collar is tightly connected to the wheel hub.
  • Page 171 To this chapter contents 14. Steering / Front Wheel / Front Cushion Installation Speedometer DISC BRAKE gear dust seal Disc Brake Apply with some grease inside of the dust seal. Install the dust seal and the front wheel side collar. Bearing spacer Apply with some grease on both sides of the speedometer gear oil seal, and then install the...
  • Page 172 To this chapter contents 14. Steering / Front Wheel / Front Cushion Place the front wheel between the front cushions. Stopper Drum Brake Align the brake panel slot with the stopper of the cushion. Disc Brake Align the flange part on the speedometer gear with the slot of cushion stopper.

  • Page 173: Front Cushion

    To this chapter contents 14. Steering / Front Wheel / Front Cushion Front Cushion Removal Remove the front fender, front lower spoiler, front cover, and front wheel as well as front brake components. Remove the brake fluid hose clipper or cable guide on the left cushion.
  • Page 174 To this chapter contents 14. Steering / Front Wheel / Front Cushion With a plastic hammer tap the steering column slightly, and then remove the top ball bearing seat. Remove the lower-end cone bearing seat on the frame with a punch. Caution Do not damage the frame and the steering column.
  • Page 175 To this chapter contents 14. Steering / Front Wheel / Front Cushion Note: 14-12...

  • Page 176: Rear Wheel / Rear Cushion

    Home page Contents 15. Rear Wheel / Rear Cushion Mechanism Diagram ··························· 15-1 Exhaust Muffler ···································· 15-3 Operational Precautions····················· 15-2 Rear Wheel ··········································· 15-3 Trouble Diagnosis ······························· 15-2 Rear Cushion········································ 15-4 Mechanism Diagram 2.4~3.0kgf-m 0.8~1.2kgf-m 3.5~4.5kgf-m 11.0~13.0kgf-m 1.0~1.4kgf-m 3.0~3.6kgf-m 15-1...

  • Page 177: Operational Precautions

    To this chapter contents 15. Rear Wheel / Rear Cushion Operational Precautions General information As for the wheel removal, service, and installation procedures, please refers to the service manual of high speed tire. Specification Unit: mm Items Standard (mm) Limit (mm) Radial Wheel wobbling Axial...

  • Page 178: Exhaust Muffler

    To this chapter contents 15. Rear Wheel / Rear Cushion Exhaust Muffler 2 Nuts Removal Remove the front-end nut of the exhaust muffler. (2 nuts) Remove the bolts. (2 bolts) Remove the exhaust muffler. Installation Install the exhaust muffler according to the reverse procedure of removal.

  • Page 179: Rear Cushion

    To this chapter contents 15. Rear Wheel / Rear Cushion Rear Cushion 2 Bolts Removal Remove the left & right side covers. (2 screws) Remove the luggage box. (4 bolts) Remove the rear carrier. (2 bolts, 2 nuts) Remove the body cover (4 screws) Remove the air cleaner bolts (2 bolts) Remove the lower nut of the rear cushion (1 bolt) Remove the upper nut of the rear cushion (1 bolt)

  • Page 180: Electrical Equipment

    Home page Contents 16. Electrical Equipment Mechanism Diagram ··························16-1 Start System ······································· 16-15 Operational Precautions····················16-2 Meter ··················································· 16-16 Specification ·······································16-3 Light / Bulb ········································· 16-18 Trouble Diagnosis ······························16-4 Switch / Horn ······································ 16-22 Charging System································16-5 Fuel Unit·············································· 16-25 Ignition System···································16-11 Mechanism Diagram REG / REC Horn...

  • Page 181: Operational Precautions

    To this chapter contents 16. Electrical Equipment Operational Precautions Charging System When remove the battery, the disconnection sequence of cable terminals shall be strictly observed. (First disconnect the negative cable terminal, next, the positive cable terminal.) MF (Maintenance Free) battery does not need to check, add electrolyte or distilled water. Battery must be taken out from scooter when charging the battery.

  • Page 182: Specification

    To this chapter contents 16. Electrical Equipment Specification Charging System Specification Items HU10U/W HU05U Capacity/type 12V4Ah / YTX5L-BS or GTX5L-BS Charging rate STD: 0.4A/5~10hrs, emergency charging: 4A/0.5hrs Battery Full charged 13.0~13.2V Voltage (20¢ J ) Under charged 12.3V Capacity 14V / 3A Between yellow-white: Lighting coil resistance (20¢...

  • Page 183: Trouble Diagnosis

    To this chapter contents 16. Electrical Equipment Trouble Diagnosis Charging System Ignition System No power supply No spark produced by spark plug Dead battery The spark plug is out of work Disconnect battery cable The cable is poorly connected, open or Fuse burned out short-circuited Faulty main switch...

  • Page 184: Charging System

    To this chapter contents 16. Electrical Equipment Charging System Wire Diagram Fuse (7A) Voltage regulator Battery / Rectifier W-White Y-Yellow G-Green Alternator R-Red B-Black P-Pink Automatic by-starter Current Leakage Inspection Turn the main switch to OFF position, and remove the negative cable terminal (-) from the battery. Connect an ammeter between the negative cable Battery (-) terminal terminal and the battery negative terminal (as...
  • Page 185 To this chapter contents 16. Electrical Equipment BATTERY 2 screws Removal Remove the battery cover (2 screws) Caution Electrolyte (diluted sulfuric acid) is very toxic. Once it spreading on clothes, skin, or eyes, it will cause burned or blind. In case of being spread, flush with great quantity of water immediately, and then send to hospital.
  • Page 186 To this chapter contents 16. Electrical Equipment Voltage Check With a digital voltage meter or multi-meter to measure battery voltage. Voltage: Fully charged: 13.0 ~ 13.2V (at 20¢ J ) Undercharged: Below 12.3 V (at 20¢ J ) CHARGING Connect the Charger positive (+) to the battery positive (+) terminal.
  • Page 187 To this chapter contents 16. Electrical Equipment Charging Voltage/Current Inspection Connect a tachometer. Turn on the headlamp to high beam and start the engine. Digital voltmeter Accelerate the engine gradually to the specified Ammeter revolution per minute and measure the charging voltage/current.
  • Page 188 Do not touch the probe of multi-meter by ● fingers, then the resistance values will be incorrect because there is some resistance existence in human body. To use the multi-meter recommended by ● SYM. Otherwise, the measured resistance might be different. 16-9...
  • Page 189 To this chapter contents 16. Electrical Equipment Alternator charging coil Caution The check of alternator charging coil and ● illumination coil can be done when the alternator is mounted on engine. Check Remove the 4P coupler of the alternator. Measure the resistance between the white wire on the alternator and frame ground with a multi-meter.

  • Page 190: Ignition System

    To this chapter contents 16. Electrical Equipment Ignition System Ignition System Circuit ENG. Start control switch Main switch C.D.I Unit Main switch Exciter coil W-White Y-Yellow G-Green R-Red B-Black P-Pink L-Blue 16-11...
  • Page 191 To this chapter contents 16. Electrical Equipment CDI. Unit CDI. Unit Removal Remove the battery cover. Remove the CDI. Inspection Disconnect the coupler from the CDI unit. Make the following inspection at each terminal of the harness side coupler. CDI. Unit Standard (at 20¢...

  • Page 192: Ignition Coil

    To this chapter contents 16. Electrical Equipment Ignition coil Removal Remove the luggage box, body cover and floor panel. Remove spark plug cap. Remove the primary coil wire of ignition coil. Remove the fix screws for the ignition coil, and remove the coil.
  • Page 193 To this chapter contents 16. Electrical Equipment Secondary coil Attached the spark plug cap, measure the resistance between plug cap side and green terminal. Standard value: 7~12kΩ (20°C) Remove the spark plug cap, measure the resistance between plug cap side and green terminal.

  • Page 194: Start System

    To this chapter contents 16. Electrical Equipment Start System Start Circuit Main Fuse switch Rear brake switch Start motor Start switch Battery Starter relay Front brake switch W-White Y-Yellow G-Green R-Red B-Black Start relay inspection Start relay Turn main switch ON. Operate the brake lever.

  • Page 195: Meter

    To this chapter contents 16. Electrical Equipment Start Motor Removal Remove the right side cover. (1 screw) Remove the air cleaner mounting bolts. (2 bolts) Firstly, remove the battery negative (-) terminal, and then remove the positive (+) terminal. Remove the luggage box. Remove the start motor power wire.
  • Page 196 To this chapter contents 16. Electrical Equipment Remove handle rear cover and meter set (2 bolts & 1 screw). Remove meter mounting screws (3 screws), and then remove meter. Starting Motor Installation Install the meter in reverse order of removal. 16-17...

  • Page 197: Light / Bulb

    To this chapter contents 16. Electrical Equipment Light / Bulb Headlight Bulb Replacement Remove the front cover (3 screws) Disconnect the headlight wire coupler. Remove the rubber boot. Press down the bulb spring locker and then remove the locker with turning it left motion. Remove the bulb.
  • Page 198 To this chapter contents 16. Electrical Equipment Position light Bulb Replacement Remove the front cover (3 screws) Disconnect the headlight and position light wire coupler. Pull out the bulb and replace it with new one. (12V/10W) Front Turn Winker Light Bulb Replacement Remove the front cover.
  • Page 199 To this chapter contents 16. Electrical Equipment Bulbs Replacement of Tail Light / Brake Light Remove the rear light lens screws. (2 screws) Remove the rear light lens. Push and turn left the bulb, and then remove the bulb. Replace the bulbs of the tail light, brake light (12V 5W/18W).
  • Page 200 To this chapter contents 16. Electrical Equipment Bulbs Replacement of Rear Winker Light Remove the rear winker light lens screws. (1 screw) Pull out the bulb and replace it with new one. (12V/10W) Bulbs Replacement of Speedometer Remove the handle front cover. (3 screws) Pull out the bulb and replace it with new one.

  • Page 201: Switch / Horn

    To this chapter contents 16. Electrical Equipment Switch / Horn Main Switch Check Remove front cover. (3 screws) Disconnect main switch leads coupler. Check coupler terminals as following pins for continuity. BAT1 BAT2 Location ● ● LOCK Main switch coupler ●...
  • Page 202 To this chapter contents 16. Electrical Equipment Right Handle Switch Winker switch Seat open switch Location FREE ● ● PUSH Wire color Black Purple Seat open switch Horn switch Horn switch Location FREE ● ● Wire color Black Light green Winker switch Location ●...
  • Page 203 To this chapter contents 16. Electrical Equipment Brake light switch The circuit of black wire and the green/yellow wire on the brake light switch should be in continuity when operating the brake lever. If the switch damaged, replace it with new one. Brake light switch Horn Remove the front fender.

  • Page 204: Fuel Unit

    To this chapter contents 16. Electrical Equipment Fuel Unit Fuel Unit Remove Fuel Tank Removal (Please refer to chapter 4 for more detailed.) Disconnect the fuel unit sender coupler. Remove the fuel level sender. Caution Do not damage or bend the float arm as ●...
  • Page 205 To this chapter contents 16. Electrical Equipment Note: 16-26...

  • Page 206: Emission Control System

    Home page Contents 17. Emission Control System Names of Mechanisms in the Emission Catalytic Converting System (CATA) · 17-4 Control System···································· 17-1 Positive Crankcase Ventilation System Function of Mechanisms in the Emission (P.C.V.) ·················································· 17-5 Control System···································· 17-1 Inspection Items··································· 17-6 Fuel Evaporative Emission Control System Countermeasure for Emission Pollutants (E.E.C.) ·················································...
  • Page 207 To this chapter contents 17. Emission Control System Fuel Evaporative Emission Control System (E.E.C.) 1. Construction: Reduce HC to pollute air. To absorber fuel vapor and saving fuel consumption Fuel tank cap (closed type) Fuel vapor separator Fuel tank Vacuum hose Fuel hose Automatic control Vapor hose...
  • Page 208 To this chapter contents 17. Emission Control System Evaporative Emission Control System (EEC) 1. Visual check: 1) Check the outside of canister for damage. 2) Check all hoses for breakage. 2. Leak test: 1) Disconnect the Vapor purge control solenoid hose, and connect a T-type hose connector to a pressure gauge and a pressure source as shown below: Fuel tank Pressure gauge...
  • Page 209 To this chapter contents 17. Emission Control System Catalytic Converting System (CATA) 1. Construction: Catalytic converter Engine Exhaust muffler 2. Description: 1) The function of the catalytic converter is to transfer unburned CO, HC, and NOx harmless CO gases. 2) Pt, Pd, Rh…etc. precious metals are used into the catalytic converter so use only unleaded gasoline to prevent from cause the catalytic converter to fail.
  • Page 210 To this chapter contents 17. Emission Control System Positive Crankcase Ventilation System (P.C.V.) 1. Construction Flesh air Fuel vapor separator Blow-by pipe Exhaust pipe Carburetor Air filter Crankcase Cylinder head Flesh air Mixture gas Blow-by Engine oil Piston 2. Principle of operation: Install a separated chamber on cylinder head, and suck the blow-by gas to the fuel vapor separator by engine vacuum.
  • Page 211 To this chapter contents 17. Emission Control System Inspection Items Secondary air injection system 1. Visual inspect the reed valve, air injection cut valve, and secondary air filter as well as hoses for damage. 2. Leaking check. 3. Warm-up running check. Fuel Evaporation Control System 1.
  • Page 212 To this chapter contents 17. Emission Control System Countermeasure for Emission Pollutants Not Within Standard as In Idle Speed (4-Stroke Engine) Conduct periodical inspection (check one time for 1500 km/6 months) Test exhaust contents at idling (note 1) Adjustment carburetor (note 2) Clean the carburetor Keep the CO value in 1.5~4.5% (note 3) by adjusting...
  • Page 213 To this chapter contents 17. Emission Control System Note: 17-8...

  • Page 214: Electrical Diagram

    Home page Contents 18. Electrical Diagram 18-1...
  • Page 215 Home page Contents 18. Electrical Diagram 18-2...

This manual is also suitable for:

Mio 100

How to Install Headlight Switch on Mio I 125

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