DAELIM VJF125 Service Manual page 274

INSPECTION
9. Check the spark plug.
Not contaminated or not
discolored.
10. Check oil level.
Level normal
11. Remove cylinder head
30mm hole cap, and inspect
lubrication.
Valve train lubricated properly.
12. Check for engine overheating.
Not overheated.
13. Accelerate or run at high
speed.
Engine does not knocking.
POOR PERFORMANCE (AT LOW AND IDLE SPEED)
INSPECTION
1. Check ignition timing and
valve clearance.
Correct
2. Check inlet pipe for leakage.
No leak
3. Check sparks.
Sparks normal.
Contaminated or
discolored
Level low or high
Valve train lubricated
improperly.
Overheated
Engine knocking
Incorrect
Leaking
Weak or intermittent
sparks
TROUBLESHOOTING
CAUSE OF TROUBLE
Lean fuel mixture.
Using spark plug with on incorrect heat
range.
Oil level too high.
Oil level too low.
Contaminated oil.
Oil level too low.
Contaminated oil.
Faulty oil pump.
Clogged oil passage.
Excessive carbon build-up in combustion
chamber.
Poor quality fuel being used.
Lean fuel mixture.
Clutch slipping.
Worn piston ring and cylinder.
Lean fuel mixture.
Excessive carbon build-up in cambustion
chamber.
Incorrect ignition timing.
CAUSE OF TROUBLE
Incorrect valve clearance.
Faulty ECU unit.
Faulty pulse generator.
Faulty insulator O-ring.
Loose throttlebody.
Carbon depasited on spark plug or spark
plug contaminated.
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