Generic Race 50, Service Manual

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55
Carburator
Idle adjustment
* Attention
The idle adjustment should be made when the engine is
warm.
It should be conducted after the warm-up of engine.
Start engine and connect the turnmeter of engine.
Adjust the accelerator pull wire and bolt stopper to specifiy
the winding number.
Winding number at idle speed
：
1750±100rpm/min
Readjust the idle adjustment bolt (2) when the gyration at idle
speed is instable or there is dificulty of slight acceleration.
Ignition timing
*Attention
Warm up engine for 3~5 minutes.
Shut down engine and connect timing lamp to spark plug
conductor.
*Notice: Please refer to instructions for timing lamp before
any operation.
Remove fender (1).
Start engine and idle it.
Check ignition timing.
If symbol “F” aligns with the mark symbol on right crankcase
cover, it indicates that the ignition timing is correct.
Raise engine speed and check if symbol “F” starts to move.
Idle speed
：
1750±100rpm/min
Cylinder pressure
It should be made when the engine is warm.
Remove the guard plate of car body.
Dismantle spark plug.
Install cylinder pressure meter.
Full throttle, press "Start" to run motor and measure the
cylinder pressure.
Check the following items if the compression pressure is too
low:
—Cylinder head gasket is damaged
—Damage of piston ring
—Ring wear
—Piston
，
cylinder , valve wear
Check the combustion chamber and the carbon laydown on the top of pistion if the compression pressure is too
Measure the
cylinder’s pressure