Jetting an '03 WR450 with YZ airbox and JD jet kit?

Can anyone help me out with tuning my carb with JD kit, and YZ airbox. I have stock exhaust with Quiet is cool insert instead of the stock insert. It doesnt seem to start first kick like it used too. Also, it has a bog down low, where it never had with the WR airbox. Any help would be much appreciated. It seemd to run perfect before the YZ airbox conversion. I live in New England at sea level. Thanks!

PM NCMountainman he did the YZ air box conversion to his 04 WR450 and has it jettted very well. :)

Oh yeah. I forgot. He was the on who helped me out with the conversion. Thanks, Indy!

what is the jetting now? with that setup i was running 48pj,120paj,170 mj,40lj,stock 04 needle(DWR) 4th clip(i think that the red jd is closest to that) but that was also with the powernow?? experiment, it took me 3 days to get my new yz 450 straight :)

I never ended up rejetting my wr after the airbox mod. It still runs ok and everything it just seems to have less power than before and stalls easier and starts harder. I am using the stock exhaust with a "quite is cool insert". Should I try the exact same jetting as you? I miss the arm-ripping power if the W. Thanks for the help, it is much appreciated!!

Thanks, Denis :)

Can anyone help me out with tuning my carb with JD kit, and YZ airbox. I have stock exhaust with Quiet is cool insert instead of the stock insert. It doesnt seem to start first kick like it used too. Also, it has a bog down low, where it never had with the WR airbox. Any help would be much appreciated. It seemd to run perfect before the YZ airbox conversion. I live in New England at sea level. Thanks!

not sure if this helps:

03 YZ450 JD kit twin air powerflow/Powernow

red needle , 170mj, 3rd clip everything else stock 900-2000ft - runs fantastic

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