One of my friends just installed FMF Fatties, and turbine core silencers, K&N Filter, snorkle removed, airbox lid on. We ride at just above sea level at anywhere from 10C to 26C. We have the 300 main jets in, needle on the 3rd clip, stock pilots and air screws out 1 1/8 turn. It runs SWEET up top but if u give it a quick shot of gas from idle(neutral) it will have like a flat spot then winds out. What should we try. Go to a 27.5 pilot or a 30 pilot, and how many turns out on the air screws. THANKS A LOT

 

Here in Anchorage, which is just above sea level, I run 27.5 270's and it runs pretty good. Best thing to do is mess around with different combo's and see how it acts. Every Banshee is different. If you go to www.bansheehq.com there are some real jetting pros in there. Do a search in for FMF Fatty jetting and you'll come up with about 100 threads at the least.

 

Toomey's website had a jetting guide at one time. Not sure if they still do, but their perfect jet kit (same as Dynojet Banshee kit) works well with the FMF also. It includes the new needles and mine is great with the 280 mains included in the kit. The needles make a difference. No need to change the idle jets.

 

You need a #30 idle jets in the carbs. Are you running the stock needles or aftermarket.