I have a 1992 KDX200 and the top end is sounding noisey. (compared to a Gas Gas trials bike) It has 2800 miles and so I was thinking it may need a new piston. However, I checked the compression and it is 180 PSI. (It was 180 PSI when it had only 180 miles too). Is a good compression reading enough to prove that the top end is good?