03 wr450f

[cubby]

Well I am working on getting my new to me bike ready for spring and I need to get the jetting right first. What I have now is 03 wr450 with a fmf 4.1 muffler, air box mod, adjustable fuel mixture screw, and I ride at 2300 feet in about 80-100 degrees. So my jetting right now is 70 leak jet,165 main jet, jd red needle on #4, 68 starter jet, and a 70 pilot jet. What is the proper jetting for where I am riding thanks.

[Wayward Son]

what is the running issue?

[cubby]

hard to start and when it is running has the low end bog and backfires on decel, and seems like I can only use 1/4 to 3/4 throttle.

[William1]

Pilot jet is too large, S/B a 45

Put the clip on 3 and do the oring mod

[cubby]

Thanks william1