How much PSI is good compression on a cr250?

8 replies to this topic
  • wht02cr125r

Posted April 11, 2011 - 12:30 PM


so i was wondering how much compression is considered to be a decent top end for a 02 cr250?

  • Blazinthetrails200

Posted April 11, 2011 - 12:33 PM


150+ should be fine anything below that would be low

  • Third-Reef

Posted April 11, 2011 - 02:06 PM


MY 97 had 180 cold with the old top end and stock piston. i just put in a prolite piston and i am getting 170 cold befor having run the bike. It wll be interisting to see what it is after i break it in and thry it warm.

  • Hairyyeti

Posted April 11, 2011 - 07:57 PM


Why change it?

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • Third-Reef

Posted April 11, 2011 - 08:35 PM


I have had my bike for 4 years and never touched the top end. If i was going to take it off, i was going to replace it. i measured the piston, and the diameter and ring grooves were right at the wear limits.

  • CRPilot

Posted April 12, 2011 - 09:30 AM


I was at 195: Fresh piston and rings, cold, with base cut and head/squish set up for race fuel on an 02.

  • Third-Reef

Posted April 12, 2011 - 07:34 PM


FYI on my 97 above where i got 170 with the new piston i checked and the squish was at .065". After i break it in and see how it runs i will pull the head and cut it for a squish of about .045 - .050 and then see ow that runs.

  • Third-Reef

Posted April 15, 2011 - 03:03 PM


Update on the 97 with the new top end. After one heat cycle and with the motor still warm i got 190 PSI.

  • wht02cr125r

Posted April 15, 2011 - 05:56 PM


ok so i checked my compression, it came to 195 cold, i havent tried it warm yet. the bike supposedly had less than 20 hours on it, but im just glad the top end is looking good.

Related Content


How much snow can my bike go threw by Joshua223

Dirt Bike   General Dirt Bike Forums   General Dirt Bike Discussion
  • Hot  121 replies

Cr125 Power Valve Adjusting by hofsviken

Dirt Bike   Make / Model Specific   Honda   Honda 2-Stroke
  • 3 replies

2001 cr250r takes a little bit to hit powerband by chanlarius

Dirt Bike   Make / Model Specific   Honda   Honda 2-Stroke
  • Hot  46 replies

cr250 woods weapon setup by jblob

Dirt Bike   Make / Model Specific   Honda   Honda 2-Stroke
  • Hot  73 replies

**BEST 125CC 2 STROKE OUT THERE** by Tobyperkins17

Dirt Bike   General Dirt Bike Forums   What bike should I buy?
  • 11 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.