Sym Wolf SB 250 Ni Service Manual page 18

B. Engine runs sluggish (Speed does not go up, lack of power)
Check and adjustment
Accelerate gradually and check
engine RPM
Engine RPM can be increased
Check ignition timing
(Using ignition lamp)
Correct ignition timing
Check cylinder compression
pressure (using pressure gauge)
Normal compression pressure
Check if the fuel injector is
clogged or not
Not clogged
Remove and check the spark
plug
No contamination or discoloration
Check if the engine is over
heated
Normal
Continually drive in acceleration
or high speed
No knocking
Fault condition
Engine RPM cannot be increased
(Test on level road)
Engine RPM cannot be
increased
Incorrect ignition timing
Abnormal compression pressure
Clogged
Contaminated or discolored
Engine overheated
Knocking
1. General Information
Probable causes
1. Clogged air cleaner
2. Poor fuel supply
3. Fuel tank emission control system clogged
4. Clogged exhaust pipe
5. Clogged fuel injector
1. clutch slippage
2. poor clutch contact surface
3. clutch shoe damaged
1. Malfunction of ECU
2. Malfunction of AC Generator
1. Worn out cylinder or piston ring
2. Cylinder gasket leakage
3. and hole in compression parts
4. Valve deterioration
5. Jammed piston ring
1. Replace the fuel injector
1. Remove the dirt
2. Incorrect spark plug heat range
3. Incorrect spark plug gap
1. Worn out piston or cylinder
2. Abnormal fuel injector
3. Poor fuel quality
4. Carbon deposit in the combustion chamber
5. Abnormal ignition timing
6. clutch slippage
1. Carbon deposit in the combustion chamber
2. Malfunction of fuel injector
3. Poor fuel quality
4. Abnormal ignition timing
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