5 Clutch problems

Clutch slipping

Insufficient clutch cable freeplay. Check and adjust (Chapter 1).

Friction plates worn or warped. Overhaul the clutch assembly

(Chapter 2).

Plain plates warped (Chapter 2). 3 Clutch springs broken or weak. Old or heat-damaged (from

slipping clutch) springs should be replaced with new ones

(Chapter 2). □ Clutch release mechanism defective. Replace any defective parts

(Chapter 2). _ Clutch centre or housing unevenly worn. This causes improper

engagement of the plates. Replace the damaged or worn parts

(Chapter 2).

Clutch not disengaging completely

Excessive clutch cable freeplay. Check and adjust (Chapter 1). Clutch plates warped or damaged. This will cause clutch drag, which in turn will cause the machine to creep. Overhaul the clutch assembly (Chapter 2).

• Clutch spring tension uneven. Usually caused by a sagged or broken spring. Check and replace the springs as a set (Chapter 2).

• Engine oil deteriorated. Old, thin, worn out oil will not provide proper lubrication for the plates, causing the clutch to drag. Replace the oil and filter (Chapter 1).

Engine oil viscosity too high. Using a heavier oil than recommended in Chapter 1 can cause the plates to stick together, putting a drag on the engine. Change to the correct weight oil (Chapter 1). I Clutch housing sleeve seized on shaft. Lack of lubrication, severe wear or damage can cause the sleeve to seize on the shaft. Overhaul of the clutch, and perhaps transmission, may be necessary to repair the damage (Chapter 2). D Clutch release mechanism defective. Overhaul the clutch cover components (Chapter 2).

Loose clutch centre nut. Causes housing and centre misalignment putting a drag on the engine. Engagement adjustment continually varies. Overhaul the clutch assembly (Chapter 2).

6 Gearchanging problems

Doesn't go into gear or lever doesn't return

] Clutch not disengaging. See above.

C

Selector fork(s) bent or seized. Often caused by dropping the machine or from lack of lubrication. Overhaul the transmission (Chapter 2).

□

□ □

J

Gear(s) stuck on shaft. Most often caused by a lack of lubrication or excessive wear in transmission bearings and bushings. Overhaul the transmission (Chapter 2).

Selector drum binding. Caused by lubrication failure or excessive wear. Replace the drum and bearing (Chapter 2). Gearchange lever return spring weak or broken (Chapter 2). Gearchange lever broken. Splines stripped out of lever or shaft, caused by allowing the lever to get loose or from dropping the machine. Replace necessary parts (Chapter 2).

• Stopper arm broken or worn. Full engagement and rotary movement of selector drum results. Replace the arm (Chapter 2).

• Stopper arm spring broken. Allows arm to float, causing sporadic shift operation. Replace spring (Chapter 2).

Jumps out of gear

• Selector fork(s) worn. Overhaul the transmission (Chapter 2). Gear groove(s) worn. Overhaul the transmission (Chapter 2).

• Gear dogs or dog slots worn or damaged. The gears should be inspected and replaced. No attempt should be made to service the worn parts.

Overshifts

Stopper arm spring weak or broken (Chapter 2). H Gearchange shaft return spring post broken or distorted (Chapter 2).

Fault Finding refmi 7 Abnormal engine noise

Knocking or pinking

□ Carbon build-up in combustion chamber. Use of a fuel additive that will dissolve the adhesive bonding the carbon particles to the piston crown and chamber is the easiest way to remove the build­ up. Otherwise, the cylinder head will have to be removed and decarbonised (Chapter 2).

3 Incorrect or poor quality fuel. Old or improper fuel can cause detonation. This causes the pistons to rattle, thus the knocking or pinking sound. Drain the old fuel and always use the recommended grade fuel (Chapter 4).

Z) Spark plug heat range incorrect. Uncontrolled detonation indicates that the plug heat range is too hot. The plug in effect becomes a glow plug, raising cylinder temperatures. Install the proper heat range plug (Chapter 1).

LI Improper air/fuel mixture. This will cause the cylinders to run hot and lead to detonation. Clogged jets or an air leak can cause this imbalance. See Chapter 4.

Piston slap or rattling

□ Cylinder-to-piston clearance excessive. Caused by improper assembly. Inspect and overhaul top-end parts (Chapter 2).

Fl Connecting rod bent. Caused by over-revving, trying to start a badly flooded engine or from ingesting a foreign object into the combustion chamber. Replace the damaged parts (Chapter 2).

I Piston pin or piston pin bore worn or seized from wear or lack of lubrication. Replace damaged parts (Chapter 2). Piston ring(s) worn, broken or sticking. Overhaul the top-end (Chapter 2).

□ Piston seizure damage. Usually from lack of lubrication or overheating. Replace the pistons and bore the cylinders, as necessary (Chapter 2).

D Connecting rod upper or lower end clearance excessive.

Caused by excessive wear or lack of lubrication. Replace worn parts.