another jetting question

i just need someone to give me a place to start (i just don't have time to read all the last post about it ) i have an 02 wr426 set the timing to yz spec's fixed the throtle stop ,cut the grey wire,removed the air box lid, and has a power core 4 on it . i'm in the phx ,az area PLEASE HELP :)

Got it, basically try close to YZ426 jetting with the following:

#45 pilot

1 1/2 - 2 turns out


#165 main

The needle part number is: 5NL-14916-EN and is an option for the '01YZ250F. This jetting is very close to a YZ426. Expect the mid-range power to come alive more like a YZ426, great for wheelies.


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