Suzuki TU250X Service Manual page 327

Complaint
Engine overheats
Dirty or heavy
exhaust smoke
Slipping clutch
Dragging clutch
Transmission will
not shift.
Transmission will
not shift back.
Transmission jumps
out of gear.
Symptom and possible causes
Defective engine internal parts
1. Heavy carbon deposit on piston crown
2. Not enough oil in the engine
3. Defective oil pump or clogged oil circuit
4. Sucking air from throttle body joint
5. Use incorrect engine oil
Lean fuel/air mixture
1. Short-circuited IAP sensor/lead wire
2. Short-circuited IAT sensor/lead wire
3. Sucking air from throttle body joint
4. Defective fuel injector
5. Defective ET sensor
Other factors
1. Ignition timing is too advanced due to defective
timing advance system (ET sensor, CKP sensor
and ECM).
2. Drive chain is too tight.
1. Too much engine oil in the engine
2. Worn piston rings or cylinder
3. Worn valve guides
4. Scored or scuffed cylinder wall
5. Worn valve stems
6. Defective valve stem seals
7. Worn oil ring side rails
1. Clutch cable out of adjustment
2. Weakened clutch springs
3. Worn or distorted pressure plate
4. Distorted clutch plates or pressure plate
1. Clutch out of adjustment
2. Some clutch spring weakened while others
are not.
3. Distorted pressure plate or clutch plates
1. Broken gearshift cam
2. Distorted gearshift forks
3. Worn gearshift pawl
1. Broken return spring on gearshift shaft
2. Rubbing or stickily gearshift shaft
3. Distorted or worn gearshift forks
1. Worn shifting gears on driveshaft or
countershaft
2. Distorted or worn gearshift forks
3. Weakened gearshift cam stopper spring
4. Worn gearshift cam stopper plate or gearshift
pawl
SERVICING INFORMATION 10-7
Remedy
Clean.
Add oil.
Replace or clean.
Retighten or replace.
Change.
Repair or replace.
Repair or replace.
Retighten or replace.
Replace.
Replace.
Replace.
Adjust.
Check with inspection
window, drain out excess
oil.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Adjust.
Replace.
Replace.
Replace.
Adjust.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Repair or replace.
Replace.
Replace.
Replace.
Replace.
Replace.