05 cr250 compression?

When I got the bike a year ago the the first thing I did was a compression test and I got 200 psi (cold, throttle open). The bike only had around 15 hours on it since new (previous owner said that dont know how true that was but it had no blow by on the piston at all). Well I put 30 hours on it and now it's at 160 psi(cold). I'm going to be doing a top end and just wanted to know if 160 is low it still has a lot of power and kicks hard. Sorry if this is hard to read I'm 14 haha. Thanks here's a picture ImageUploadedByThumper Talk1383177801.672333.jpg

160 seems low for an 05-07.  I know CamP got 215 before he cut the cylinder (now has 235).  I never tested my 06.  Of course different testers will get different results too.

160 seems low for an 05-07. I know CamP got 215 before he cut the cylinder (now has 235). I never tested my 06. Of course different testers will get different results too.

i used the same tester both times and yes different testers will be different. I read on his thread about it being 215 before he cut the cylinder too and I got 200 when i got the bike so I was pretty happy but it's due for a top end now and it's also cheap insurance! I also pulled up and down and side to side on the flywheel and not even the slightest movement. I have a few testers and they are all the more pricy ones and not junk like some of them. I'll try again with a different one when I get time thanks.

160 is low

Should be about 215-220 psi with a stock motor. But could be as high as 250 on a built motor.

I had 225 stock with new vertex piston. With one of my set ups, I cut the cylinder .025", head .020", to get my squish clearance down from .084" to .040". I had to cut 2cc out of the dome and reshape it so comp was not to high. When I was finished I had 245 psi, 15.1:1 comp and needed to run 100LL.

Edited by Kirkes

160 is low

Should be about 215-220 psi with a stock motor. But could be as high as 250 on a built motor.

I had 225 stock with new vertex piston. With one of my set ups, I cut the cylinder .025", head .020", to get my squish clearance down from .084" to .040". I had to cut 2cc out of the dome and reshape it so comp was not to high. When I was finished I had 245 psi, 15.1:1 comp and needed to run 100LL.

i figured it was this motor has some hours on it so its getting a top end

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