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bad bog, accelerating, braking bumps...

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I just put an fmf exhaust on my bike, with the power up jet kit....i put in the jets that the kit told me to do, and now it has a terrible bog when accelerating out of turns, and when hitting steep jump faces, and when acclerating over braking bumps...it does this low in the gear and sometimes mid-high rpms...the bike feels and has a smooth rpm but the bog makes it suck. its a fmf powerbomb header and the 3.1 exhaust....i put in a 145 main jet, 48 pilot, fuel screw 2 out (tried diff positions , no help) stock needle on 3rd clip. Does anyone know what could be causing it, does it sound like a jetting problem? also its aobut 40-50 degrees and sea level

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what year bike. the main seems way to lean. this time of year you should be some where 178 to 185 main pilot is too rich go to 45 and fuel screw is about right maybe a half to 3/4 more out. leak jet should be 40-55. I am running a 185 main 42 pilot and 55 leak. it runs good but I will try a 45 pilot.

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doesn't matter the year, if your too rich the bike will not perform as well, to lean and you get super heated air and overheating usually

year only matters for carb, but you have a Keihin FCR MX37 with tps

if its a wr it comes leaned out for emmissions

if its a yz then its good

i think the clip needs to be on the 4th position down

I run a 178/180 main

Did you buy an exhaust slip on for a 450, just currious because i think its interchangeable and the 450 uses smaller jets

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If it is a Wr I dont know you will have to check database, But if it is a Yz go 180 main 42 or 45 pilot 40 to 55 leak 3rd clip down and about 2 1/2 fuel screw. If it is a yz I cant belive FMF would reccomend a 145 main.

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