Compression psi rating for 125's

[Big Daddy]

What should be the compression psi range for an 98 CR125.
I have 115psi kicking it hard 10 times with gas open.
I bought the bike used early this year. Is it time for a rebuild?

 

[Glitch]

I think a healthy compression for a 125 is around 150-160. So yes, you should rebuild the top end.

 

[125 rider]

yea, its definatly time.

 

[cr25096er]

i wouldnt even run it at all w/ compression that low. my 91cr125 w/ a fresh top end had 180psi in just a few kicks.

 

[MikeyG]

It should, cr25096er. It can run with 110, but I think the compression tester may be faulty.

 

[Big Daddy]

Update! I tore the topend apart, the cylinder mearsured 2.1251-2.1255. But the piston didn't fair very well. 2.1220 at the skirt and 2.114 right below the ring. :eek:
How much should the piston taper for top to bottom, about .0020?
The bike ran fairly well but lacked top end.
Getting a Pro-X piston set with .012 base gasket kit. (stock is .020)
Sounds like I should be in the 160-185 psi range.

 

[A-RustyDemon]

Well according to honda service tech. The 125 CR should have a reading of 135-145. When you get a reading of 118-120 time to replace.