miss fire

[steverb]

i know this has been asked a million time but i haven't herd of someone solving the problem.

 

i have a 2004 banshee and its miss firing out of the left cylinder. her is a video of someone else bike acting the same 

 

here is what I have done so far. did a compression check it was around 100psi so i had the topend rebuilt,

put new read in v force 4s

pulled the carbs cleaned them. look for anything abnormal didn't see any thing, also pulled the carb of my friends running banshee and tried that.

tried swapping the plugs wires over, new plugs again and after that no change.

 

this is what has been done to the banshee. toomy t6 pipes, 280 jets, cut air box, im at sea level

 

bike ran fine with this until i parked it for a couple of months. my last trip was at Winchester bay and had no problems until i took it out the next time.

Edited July 30, 2014 by steverb

[Bennett131]

100 psi is getting low for starters

[steverb]

Thats why I rebuilt the top end. Bored and new wisco pistons.

[Starwriter]

Air leak or squirrels packed the left pipe full of walnuts. You did a leakdown test after you rebuilt the topend, right?

[Tallen32]

Had the same issue with mine. Except right cylinder. Turn on your choke and see if more smokes comes out. If it does. Check your pilot jets. I cleaned mine 3 times and still had the same problems. Left cylinder would smoke more and right would not and stay cold until I went past half throttle. Would also misfire. Decided to buy bigger pilots went to 27.5s. After taking the carbs apart again to install them I check the stock pilots side by side to reference the hole sizes. Sure enough the right pilot was smaller and clogged up. I put in the 27s anyways and now they are both even. Synced and bottom is more more responsive.