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95 compression on both cylinders


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its possible that its just the rings are worn.

only off by 15 psi you should be good

but if you do decide to rebuild if theres no major sratches in the cylinders or on the head (a machinist could tell you if your good) then you could just do a hone which takes out the fine little scratches you will be could.

you will gain from a rebuild but i dont think you need one. new rings hone and pistons should do the trick.

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Different compression gauges read different numbers. Sometimes even gauges of the same brand and model read different numbers. Unless you have a calibrated gauge or you have previously logged a reading on that exact motor with a fresh top end with that exact same gauge... 90 psi is as good as 140 psi IMHO. With what relevant info you have provided so far... Both cylinders read the same and the bike runs real strong, you can either pull the head and possibly cylinders for inspection, just run it as is or you could just go ahead and fix something that probably isn't even broken to start with.

Replacing a top end simply due to a low compression gauge reading obtained through a questionable gauge and method when both cylinders blow exactly the same and the engine runs good makes about as much sense to me as estimating fuel octane requirements with the same method and numbers...

 

i removed both spark plugs, its a star products tu-3 universal compression tester, i held the throttle wide open, she hit exactly 90 on both cylinders, im basically at sea level,maybe 50ft up ahha, the bike hauls ass still, i just yesterday i ran faster than a outlaw 525 piped and jetted and she was 09, just wondering if a fresh top end would make her faster? or "if it aint broke dont fix it".....also how much should i get her bored out, what pistons? is there anything else that i would have to change to compensate with the new hp? thanks !!
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also how much should i get her bored out, what pistons?

 

The least you need to get bored... Cats have 9 lives... Each over you go, you're losing another life... I think 100 over is the most you can go... after that, it's pretty much gone. Clean it if you can, or do 10 over.

 

Wisecos FTW.

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