If it is a 2 cycle, I'm not familiar with kymco, the only way to fix the compression is to replace the piston rings and/or piston. It is not uncommon to burn a hole in a piston if the carberator is gummed up. If it is a 4 cycle (probably isn't) you could have a burnt, warped, or sticking valve. Either one it requires taking the head off for further evaluation.
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If it is a 2 cycle, I'm not familiar with kymco, the only way to fix the compression is to replace the piston rings and/or piston. It is not uncommon to burn a hole in a piston if the carberator is gummed up. If it is a 4 cycle (probably isn't) you could have a burnt, warped, or sticking valve. Either one it requires taking the head off for further evaluation.