compression test results.......

[jwags13]

Just picked up quad from shop and the compression test yielded 155psi. Should i freshin up the top end before riding? If so just rings or piston and rings? Thanks for the help.

[jcs003]

that would be ok on a purely stock motor. do you have any specifics on the motor?

[DnB_racing]

did you use a quality tester??at 155psi is the minimum ... I would run it a little while to make sure everything else is good, so you only have to open it once

[jcs003]

another thing is to get a good test is after it has been warmed or by adding a few drops of oil in the spark plug hole to allow the rings to get a good seal.

[jwags13]

The previous owner said it is a ct 310 but im not really sure what it is. All in know for sure is that it is a pro-x cylinder just by what people have been tellin my on this forum. The quad is in the other thread, http://www.exriders.com/vbb/showthread.php?s=&threadid=462069

[k7mm]

It's probably time for a new top end.155psi seems pretty low.I would change the piston,and the rings both.Then you'll be nice and fresh for the whole riding season.You probably just have worn rings,and do not need to bore,but I would still change the piston,myself,but of coarse you could just change the rings.If the guy told you that the cylinder is a 310,then it probably is.You wo'nt know what bore it's on until you pull it apart.

[machwon]

if the carb is well tuned, does it start on the first or second kick? Unless you know what your gauge reads with a fresh motor, always get a second opinion with a buddies compression gauge. I've seen gauges vary by 30-40 psi.

[jwags13]

Ive only had it for a week, but yes it always starts first or second kick. I think im gonna throw a fresh piston and rings in her just to be safe.