jetting for 04 Crf250r

[MKraft649]

i am buying a white brothers aluminum race series for my 2004 honda CRF250R. I have had trouble jetting it for the cold temps. and have heard many different things. I was wondering if anyone knew what jet i should use for my new exhaust system. If you know of anything or any kind of kit for this stuff please let me know. thank you.

 

[slodsm]

I have only had experience with one kit but when I put the FMF factory 4 on my 05, I went to the FMF stage one kit, changed to their needle and used the 154 main DOWN from the 172 they use stock I believe. It made all of the difference in the world with both starting and off idle responce. I notieced no difference up top after jetting but low to mid range difference was stupid.