05 wr 450, popping during decel wi/FMF pipe/header

quick question for my buddies.... Installed an FMF Powercore and s/s header. Was running 170 m, 48 pj and 1 3/4 turns out on f/m all ran fine with stock exhaust. Put new set on and can't seem to get rid of the decel popping. Have moved needle setting up and down one clip no difference. Also tried running the JD red needle on 4 from the top no real change, even when I'm at 2 3/4 on the f/m. Tuning location Socal, I've read most of those jetting sites, too many combos. Should I buy the Boyesen fuel excel ??

Problem solved, air leak at header flange to head. 170mj, 48 pj and clip 4 seems fine. Time to ride.

Problem solved, air leak at header flange to head. 170mj, 48 pj and clip 4 seems fine. Time to ride.

I went to a 50 pilot and 175 main..

My FMF setup does the same thing. It sucks air in whare the header and midpipe come together. Som High temp silicone under your clamp and you will be fine.

My FMF setup does the same thing. It sucks air in whare the header and midpipe come together. Som High temp silicone under your clamp and you will be fine.

Dont use silcone... There is a gasket in the head made for this.. silcone wont last and its called RIGGING!!! Dont RIG yer WR...

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