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trying to get a read if I have high compression pistons. I have no contact with PO. 02 twin cam 88, probably been cammed. I did a compression check on a cold bike, no oil squirted into the cylinders. got 140 pounds in each? Thoughts? Thanks everyone.
 

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Not high comp. from that number.
Squirt oil in cylinders, hold throttle wide open and crank for 10 revs. on each cylinder. Post the #s.
 

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IMO you can't tell if you have high compression pistons by doing a compression test. Too many factors of cam specs. involved. Not counting conditions of valves rings, etc.
 

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Agreed ^
I would also do it with a warm motor...u can have 10:1 pistons but have a big enough cam to drop cranking psi low to make u think u have flat tops or even dished pistons...get a bore scope
 

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trying to get a read if I have high compression pistons. I have no contact with PO. 02 twin cam 88, probably been cammed. I did a compression check on a cold bike, no oil squirted into the cylinders. got 140 pounds in each? Thoughts? Thanks everyone.
That has less compression than an untouched engine, probably over-cammed, unless another issue.
Scott
 
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