um CHILL 125 cc. Service Manual page 40

4 If the issue only occurs in winter, check the oil and gear box oil.
5 Check whether the engine rotation resistance is too big or not.
ITEM OPERATION
1
Check whether the fuel pump pressure is about 250kPa at idle.
2 Check whether the 'RMP' data on the diagnostic tool shows the real engine RPM.
3
Pull out the spark plug, check whether the spark over is normal.
4 Check whether the cylinder pressure is normal.
CHILL 125 cc. SERVICE MANUAL AND EFI DIAGNOSTIC
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RESULT
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Change the oil
Next
Check the engine
Help
NEXT STEP
Next
Check the pump.
Next
Check the crank sensor.
Next
Check the ignition system
Engine is good.
Check the engine
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