05 800HO compression

[piper907]

I just did a compression test on my 05 REV and got 92-96 psi at 500' elevation... this seems a bit low to me considering my 2001 had 140-136 after a set of wiseco pistons and rings.
What are typical compression readings for an 800HO motor... Is there a fresh top end in my near future???

 

[MARCUSO]

I know it should be higher...

I bet you need 140 for sure...130 minimum

Pull it apart, check the rings, and your tolerences... are they original??

The outer edge starts flaking.

 

[piper907]

yea, they are OEM... I believe that the previous owner had to have one piston and jug was replaced at the beginning of last year.
I am still waiting for my workers manual in the mail so I don't have any references exept this forum for now.
I believe I need to do another compression test...
WITH THE THROTTLE OPEN (oops)

I'll post the new results.

 

[louie]

I would say yes, you need probably freshen the top end. My05 800HO had135-140 psi with about 900 miles on it when i got it. Another way to tell if tou suspect rings is to add some oil to the cylinders and take another reading, if it goes up, then whalah, bad rings.

 

[Rave]

Mine has 160 + at 1200 feet. Had Big John's Trail Torquer kit installed 400 miles ago. Room temperature engine, wide open throttle.