KEEWAY 50cc Series Service Manual page 41

If engine compression is below specifications, repeat test procedure, placing several
drops of oil into combustion chamber JUST BEFORE connecting compression gauge.
If the compression rises to within range, there is excessive wear or damage to the
cylinder, piston, rings, or cylinder head/gasket.
Ensure proper valve timing and seat
Ensure proper cylinder head gasket seat and seal, and proper torque applied to head bolts.
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