FMF System w/ Barnum Airbox Kit on WR450

I just installed the Barnum's Pro Airbox Kit to complement my PowerBomb/Q2 setup. I figured the bike should suck as well as it blows :naughty: . One question though...I was running a 170 main, #40 Leak and Boyesen Quickshot which totally cured my off-idle bog, but with the addition of the Barnum's, the bog is back. I've gone all the way up to a 178 Main and that cured most of it, at least it doesn't stall now with a snap of the throttle from idle. Also, the bike no longer responds to any fuel screw input. I was thinking about going to a 180 Main and having a 182 on hand just in case. My thinking though is that I may be getting too rich and might start to foul plugs. Perhaps I should look into going smaller on the leak jet as well. I'm just not sure where to go next...SC

Current Settings:

178 Main

45 Pilot

65 Starter

40 Leak Jet

80 PAJ

JD Red #4

Boyesen Quickshot ACV Cover

Fuel Screw: 0 Turns (No Response)

Temp: Mid 60's

Elevation: 5000'

Airbox: Snorkel-ectomy & Barnum's Airbox Kit

Result: Small Off-Idle Bog, No Fuel Screw Response


the main has nothing to do with the off idle bog,what you've done is richen the main so much its overlapped the pilot circuit(which is the reason you have no adjustability) put in the 48 pj with a 170 main still on 4th clip :naughty:

I switched back down to a 172 and that helped, but I haven't changed the pilot yet. I wanted to change the PAJ to a #100, but it's backordered everywhere. I also tried a 170, but still had no fuel screw adjustment. Won't increasing the Pilot make matters worse with regard to the fuel screw?...SC

pull the a/f screw all the way out and make sure the tip hasn't broken off,sometimes if turned in too tight when setting it'll snap the little tittie up in the seat. be careful there is a spring ,washer,and o-ring up there :thumbsup:if its good try the 48, most everyone with aftermarket exhaust is running the 48pj, i can only run the 45 after it turns 90'F. and i ride at 4500' ? these are just my thoughts and experience,i'm definately no pro-fessional :naughty: where are all the pro-fessionals when ya need one? kinda like cops :naughty:

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