Need help with jetting! 2007 Crf 250r

I just bought brand new pro circuit ti-4r duals for it(cant wait to try em out :cheers:) i was wondering if anybody had any jetting tips or what your running in the same setup.... im in 0-1000 elevation and 70-100 degrees. any help would be most appreciated!

You shouldn't have to do much other than maybe adjust the air/fuel mixture screw. The pipe doesn't effect the jetting as much as the 2 strokes.

R u sure? I've been told to buy a jd jet kit.. and that id have to change the leak jet and the pilot jet

jd jetting is all im going to say man!

You shouldn't have to do much other than maybe adjust the air/fuel mixture screw. The pipe doesn't effect the jetting as much as the 2 strokes.

+1. my buddy put a fmf on his yzf 250 he just turned the screw out another 1/4 to 1/2 turn somewhere in there and it runs great.:cheers:

I've installed the MRD's, DRD's, FMF's and only 1 Yoshi. The yoshi I had to change the main, but after looking, it had a 178 in an 08. It was too fat to start with. The rest required adjusting the mixture screw. If the jetting is pretty close to start with, I'll repeat, you should only have to adjust the fuel air mixture screw. If you have to re-jet the bike, it was probably out to begin with or it's at one end or the other and the slightest change of anything is going to cause the jetting to be off by one size.

just adjust the fuel screw.

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