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Help.? With Jetting 06 YZ250F with FMF 4.1

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Need a little help with jetting my 06 250F. I just put on my FMF 4.1 Factory full/with the powerbomb header. What are the jetting specs I should set?

Thanks

-Jon

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Dont know the exact jets you need to use but i do know this. You will have to go a little richer since that exhaust is letting it breath better.

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i would like to know that also. i'm going to buy my buddy's fmf 4.1. i live in florida at sea level. i searched all night on this sight looking for a answer but the ones i did find always had something else added to the mix. i couldn't find a 06 yz250f owner that installed just the fmr 4.1 with powerbomb header.

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Dont know the exact jets you need to use but i do know this. You will have to go a little richer since that exhaust is letting it breath better.

Actually a good aftermarket exhaust system like the FMF requires a slightly leaner setting on the main jet. This is due to a stronger carb signal during valve overlap. Where the exhaust system pulls intake when both the intake and exhaust valves are open.

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