Running Werid

[STLbanshee]

Like if you hold the throtle at like a 1/4, then push it to WOT quickly it like bogs, then back fires..what is the problem? I have fmfs ssts, k&n with no lid, and 280 jets, nothing done to the pilot jets..

[Checkmate]

sounds lean. try runing in your adjustment screws, and raising the needles.

[STLbanshee]

I got the air/fuel screws at 2 turns out, so your saying screw them into where?

[BenBB]

I agree, backfire is usually a symptom of being lean. Are you sure the mains aren't lean? You might try going up a size on the mains and see if anything changes, once you know for sure the mains are dialed in (and not still lean, depending on temp, elevation, premix ratio, etc. I'd think you need to be in the 300-330 range for mains), if the problem persists you can try adjusting the needle clip position and see what that does. Good luck.

[Ducman]

I agree with BenBB 300 - 330 on the mains. I have FMF Gnarlies and a foam twin air filter with #30 pilots, air screws 2.5 turns out and #260 mains with the lid on and would probably be at #270 or 280 with the lid off so with your higher reving pipes, K&N, and lid off I also think that you are very lean.

[STLbanshee]

If Im running lean, why is it leaking gas when the bike it running? So if its running lean, the plugs will be whiteish color right?

[kotin6]

I have a simular problem with simular mods/ (sst pipes and silencers, K&N filter, boostbotle, snorkel off) I am waiting on main jets from 280 thru 340 and 30 pilots soon as they are in Ill let you know what works best for me

[Ducman]

If Im running lean, why is it leaking gas when the bike it running?   So if its running lean, the plugs will be whiteish color right?

Sounds strange, the leaking gas may be a float problem. I suppose the whole delima could be a fuel supply problem because of that? Whiteish plugs are an indication of a lean condition but the only way to determine if the main jet circut is lean is to use a new set of plugs and do a plug chop following the banshee jetting FAQ instructions. For example, you could be rich on the pilots which would make the plugs a nice brown color indicating every thing is ok and the mains can still be lean.

 

http://www.dfn.com/benkaren/jetfaq.html

[Checkmate]

I got the air/fuel screws at 2 turns out, so your saying screw them into where?

try putting them at 1 turn out and see if it helps...if not turn them back out to 2 turns.

[spoin39]

It sounds like you need to move the needle up a notch, check your floats to see if they are set right (20-22mm). I agree that the mains should be richer but that is not the problem at 1/4 throttle.

[mattmans1983]

I like the airscrews answer. Adjust them in 1/4 turn at a time and ride it between each adjustment.

[southernbanshee33]

i had the same problem on my banshee one time and found out that one slide was stuck open. the thing was smoking bad and running horribly. it would back fire when i popped the throttle open. luckily i did not run it but about five minutes like this to get back to the truck and some tools. take a flashlight and look through the sight glass on each carb. while working the throttle. if one is stuck, you will be able to tell.

[Shee_Rookie]

Hey STLBill, did you find out what the problem was? My bike is doing the same thing and I was thinking old gas because I had premixed gas sitting in one of my cans for awhile and this happened after I filled her up. I'm going to drain it and fill up with fresh premix to see if this corrects it. Just kinda curious..