CR 265 jetting

How's it going guys. New member here looking for some jetting tips. I have looked all over but haven't been able to find any help.

I have a 04 CR 250 with a eric gorr 265 in it. Full Pro circuit exhaust and v force cage. I bought the bike with a keihn airstriker on it and recently bought a JD jet kit for a 1999-2000 cr250 as well.

Since I have owned the bike I have had nothing but trouble trying to get the jetting right as I'm not very good at it. I'm wondering if anyone can help me with some base line jetting specs? I am at sea level and temperature has been between 60 and 80 degrees lately. Any help would be appreciated, thank you


Red needle 4th clip position, 45 pilot jet, 178 main. The blue needle is identical to the red needle but is richer from 0-1/4 throttle so if the bike feels lean in that throttle range use the blue needle. Also jd is a great resource for jetting help, call him.

Thanks for the help. I did call him but he didn't offer much help. He just told me to go off of the 2000 cr250 jetting specs but wasn't sure seeing as it is a big bore

His 00 jetting guide would work as a baseline. Normally the EG bb's like leaner jetting than stock but the guide would get you in the ball park.

Thanks so much for your help man. I've been beating my head into the wall trying to figure this out lol

Thanks so much for your help man. I've been beating my head into the wall trying to figure this out lol


Just a reminder that my suggestion is conservatively rich.  I would try those settings at sea level on a 250 so if it feels rich, then the first thing I would try is a 1 size leaner main jet (175) and then retest, if it is still too rich, try one clip leaner on the needle (3rd clip) and retest.  Do small incremental changes and document what you feel with the way the bike sounds and feels.  Make sure you get the bike nice and warmed up before doing much testing.  It is best to test at a track since the bike really never gets completely up to operating temp running up and down the street. 

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