Suzuki GW250 Service Manual page 416

10-6 SERVICING INFORMATION
Complaint
Engine runs poorly
in high speed range
Symptom and possible causes
Defective engine internal/electrical parts
1. Weakened valve springs
2. Worn camshaft
3. Valve timing out of adjustment
4. Too narrow spark plug gaps
5. Ignition not advanced sufficiently due to poorly
working timing advance circuit
6. Defective ignition coils
7. Defective CKP sensor
8. Defective ECM
9. Clogged air cleaner element
10. Clogged fuel hose, resulting in inadequate fuel
supply to injector
11. Defective fuel pump
12. Defective TP sensor
Defective air flow system
1. Clogged air cleaner element
2. Defective throttle valve
3. Sucking air from throttle body joint
4. Defective ECM
5. Imbalanced throttle valve synchronization
Defective control circuit or sensor
1. Low fuel pressure
2. Defective TP sensor
3. Defective IAT sensor
4. Defective CKP sensor
5. Defective GP switch
6. Defective IAP sensor
7. Defective ECM
8. TP sensor out of adjustment
9. Defective ISC valve
Remedy
Replace.
Replace.
Adjust.
Adjust.
Replace ECM.
Replace.
Replace.
Replace.
Clean or replace.
Clean and prime.
Replace.
Replace.
Clean or replace.
Adjust or replace.
Repair or replace.
Replace.
Adjust.
Repair or replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.