Cylinder Compression Pressure; Drive Belt - Sym GTS 250 Service Manual

Cylinder Compression Pressure

Warm up engine.
Turn off the engine.
Remove luggage box and central cover
Remove spark plug cap and spark plug.
Install compression gauge.
Full open the throttle valve, and rotate the engine
by means of starter motor.
Caution
Rotate the engine until the reading in the gauge
no more increasing.
Usually, the highest pressure reading will be
obtained in 4~7 seconds.
Compression pressure¡ G 12±2 Kg/cm²
Check following items if the pressure is too low:
Incorrect valve clearance.
Valve leaking.
Cylinder head leaking, piston, piston ring and
cylinder worn out.
If the pressure is too high, it means carbon
deposits in combustion chamber or piston head.

Drive Belt

Remove mounting bolt located under air cleaner.
Remove the engine left side cover and the cover.
Check if the belt is crack or worn out.
Replace the belt if necessary or in accord with the
periodical maintenance schedule to replace it.
Width limit: 22.5 mm or above
Clutch Disc Wear
Run the motorcycle and increase throttle valve
opening gradually to check clutch operation.
If the motorcycle is in forward moving and shaking,
check clutch disc condition. Replace it
To this chapter contents
Spark plug cap
2. Maintenance Information
Compression gauge
Teeth
Clutch lining
Width
Clutch weight
2-9