understanding compression test results

[gsxr400 91]

compression test results
-----1----2----3----4----
Dry 130/110/30??/162
Wet 150/180/160/200

The 3 cylinder dry test... May have gone wrong not sure if the gauge were fastend in correctly.

Kinda guessing if it were right then piston ring gone???

What about the overall results are they good or bad ???

No valve clearences adjustments have been made as not sure how to or confident in doing so.

[Marsbar]

dirty/corbonized valves is a common problem. I was getting 115 psi from 3rd cylinder.

could take head off, clean/ re-lap all valves, put all back and see then. Only cost about £30 for gasket + lapping compound. Better then £56 per piston ring set x4. You could always do some porting whilst valves are out also, really improves the air flow. Got 69bhp outta mine before set-up but that was with bbk also :/

[Awynn]

If that 30 was right and it came back up wet then it points at rings/bore damage/wear, if bike runs I would start up and run out oil and retest. No1 is still low and didn't come up much wet so points at valves (possibly head gasket)

[gsxr400 91]

I watched a vid on u tube about this test... This guy said if you get two readings identical side by side (cylinders 1+2 or 2+3 etc) would suggest head gasket gone.

How easy is checking the valve clearence ? ?

The carbs are still off the bike awaiting further parts for the rebuild. How long should wait to re test cylinder 3?

What would be ideal results??

Cheers