I just did a compression test on my 800ex both sides are putting out 120psi is that right or do I have some trouble?

[2015 Z Force 800 53/Trail EPS]

Without looking at the book, I believe that's right-on.

good because I thought the rings where shot, just valve seals I guess.

[2015 Z Force 800 53/Trail EPS]

Just looked at the manual and it says it should be 1000kPa which is 145.038psi. Yours is a little low but not that bad...and it could be valves. A leakdown test would tell you which.

I've got new seals just sitting in the packages so hope that just it.   I've got a rattle inside do you think the tensioner might be loose? are something like that?

[2015 Z Force 800 53/Trail EPS]

I've got new seals just sitting in the packages so hope that just it.   I've got a rattle inside do you think the tensioner might be loose? are something like that?

Been a few tensioner issues so check while in there.

Have you checked valve adjustments? I have seen a lot of low compression motors caused by tight valves.