This guide repair service manual has been specially prepared to provide all the necessary information for the proper maintenance and repair of the SD-50.
The SD-50 is a new type of motorcycle that has many technical features such as :
※ V-belt drive automatic transmission
※ Forced air-cooling system
※ P.E Ignition system
※ Electric starter system
The SD-50 fits the needs of a wide variety of motorcycle users. Those who will be servicing this motorcycle should carefully review this manual before performing any repair or services. Information of this manual is up-to-date at the time of issue. Major modification and changes incorporated later will be advised to HYOSUNG product distributor in each market. Therefore, if newest information is requested in the future, please contact the local HYOSUNG distributor.The SD-50 motorcycles distributed in your county might differ in minor respects from the standard specification and, if they do, it is because some minor modifications (which are of no consequence in most cases as far as servicing is concerned) has to be made to comply with the starutory requirements of your country.
pdf Download now Hyosung SD-50 Sense 1999 Workshop Service Repair Manual.
This Repair Manual Covers:
- MODEL IDENTIFICATION
- FUEL AND OIL RECOMMENDATIONS
- BREAKING-IN PROCEDURE
- PRECAUTIONS AND GENERAL INSTRUCTIONS
- SPECIAL MATERIALS
PERIODIC MAINTENANCE AND TUNE-UP PROCEDURES
- PERIODIC MAINTENANCE SCHEDULE
- MAINTENANCE AND TUNE-UP PROCEDURE
- CYLINDER HEAD NUTS AND EXHAUST PIPE BOLTS
- CYLINDER HEAD AND CYLINDER
- SPARK PLUG
- FUEL LINE
- AIR CLEANER
- THROTTLE CABLE
- ENGINE IDLE SPEED
- OIL PUMP
- FINAL GEAR OIL
- FRONT SUSPENSION
- REAR SUSPENSION
- CHASSIS BOLTS AND NUTS
- GENERAL LUBRICATIONS
- ENGINE REMOVAL AND REMOUNTING 3- 1
- ENGINE REMOVAL 3- 1
- ENGINE REMOUNTING 3- 3
- ENGINE DISASSEMBLY 3- 4
- ENGINE COMPONENTS INSPECTION AND SERVICING 3-13
- BEARINGS 3-13
- OIL SEALS 3-13
- CRANKSHAFT 3-13
- AUTOMATIC CLUTCH INSPECTION 3-14
- CYLINDER HEAD 3-16
- CYLINDER 3-17
- PISTON 3-17
- REED VALVE 3-19
- ENGINE REASSEMBLY 3-20
- OIL SEALS 3-20
- BEARINGS 3-20
- BUSHINGS 3-21
- CRANKSHAFT 3-22
- CRANKCASE 3-23
- CENTER STAND 3-24
- REAR AXLE SHAFT, BRAKE AND WHEEL 3-25
- TRANSMISSION 3-27
- STARTER DRIVEN GEAR AND STARTER MOTOR 3-29
- MOVABLE DRIVEN AND CLUTCH 3-30
- MOVABLE DRIVE 3-33
- KICK STARTER 3-35
- PISTON 3-36
- OIL PUMP AND INTAKE PIPE 3-38
- MAGNETO 3-39
- MUFFLER 3-40
Complaint:Engine does not start, or is hard to start
|Compression too low
1. Excessively worn cylinder or piston rings.
2. Stiff piston ring in place.
3. Gas leaks from the joint in crankcase, cylinder or cylinder head.
4. Damaged reed valve.
5. Spark plug too loose.
6. Broken, cracked or otherwise failed piston.
Plug not sparking
1. Damaged spark plug or spark plug cap.
2. Dirty or wet spark plug.
3. Defective CDI & Ignition coil unit or stator coil.
4. Open or short in high-tension cord.
5. Defective ignition switch.
No fuel reaching the carburetor
1. Clogged hole in the fuel tank cap.
2. Clogged or defective fuel cock.
3. Defective carburetor float valve.
4. Clogged fuel hose or defective vacuum hose.
Refair or replace.
Refair or replace.
Clean and dry.
Clean or replace.
Clean or replace.
|1. Carbon deposited on the spark plug.
2. Defective CDI & Ignition coil unit.
3. Clogged fuel hose.
4. Clogged jets in carburetor.
5. Clogged exhaust pipe.
|Noise appears to come from piston
1. Piston or cylinder worn down.
2. Combustion chamber fouled with carbon.
3. Piston pin, bearing or piston pin bore worn.
4. Piston rings or ring grooves worn.
Noise seems to come from crankshaft
1. Worn or brunt crankshaft bearings.
2. Worn or brunt conrod big-end bearings.
Noise seems to come from final gear box
1. Gears worn or rubbing.
2. Badly worn splines.
3. Worn or damaged bearings of drive shaft for rear axle shaft
Magneto charge, but charging rate is below the specifications
|1. Lead wires tend to get shorted or open-circuited or
loosely connected at terminal.
2. Grounded or open-circuited stator coils of magneto.
3. Defective regulator/rectifier.
4. Defective cell plates in the batttery.
|Repair, or retighten.
Replace the battery.