CBR 600, '96 F3 i picked up not running and he said a guy at a bike shop in st pete diagnosed it as a head gasket failure...so i got a deal and said i'd fix it myself...turns out, we took off the header, carb, and got the head off...the gasket looks fine. I can't find any damage where the oil was leaking out (under the #1 cylinder (closest to the timing chain)). we saw it comming from under the header, but the only gasket we found that was bad was the valve cover, the seal around the #1 spark plug was torn up. Did a compression test, and they were all normal, except cyl #1. we're going to replace both the head and valve cover gaskets. Was the valve cover gasket the problem? if not what else should i look for that would make a compression loss??

 

Rings?

 

Valve cover makes no difference to the combustion chamber compression although it could be the cause of oil leaking. Rings and head gasket is all.

 

Yeah, if you've got compression loss and oil coming out around the header mating surface, time to think about rings or valve guides (which do go bad on Hondas). Did you do the compression test properly with a warmed up engine and all of the plugs out? Also, did you use a new head gasket when you put the head on? Putting on an old head gasket would definitely cause compression loss

 

A bent valve or incorrect valve adjustment. And both of those could cause it to lose compression.

 

it is both the rings and valve guides. unless it is a high mileage bike i would say the valve gides more than likely. but you know since you have that much apart you should replace any gasket or seals that you have accesses to know. just a thought. may save you from haveing to go back in there for a long time.