Ok. I have FMF Fatty pipes, had the PowerCore 2 silencers and I got rid of the PC 2s for some Toomey silencers. Along with the new silencers I decided to run open air box with an Outerwear on the K&N (something I only do when I'm dune riding). Obviously, the machine would run leaner with this setup, but I was previously running slightly rich to be safe. So it should have been running just about right. Anyway, now there's this problem where it will fire right up like always but after running for a couple seconds the left cylinder isn't firing and the right one is so it just kind of drags the left. Thinking this was a jetting issue I went through the carbs many times trying different combos and it still had the same problem. I went back to the way I had the carbs set up before I put the new silencers on. Then I tried cleaning the contacts on the coil and the spark plug caps and put new spark plugs in- still had the same problem. I really don't think it's the coil because I replaced that about a year ago when it was acting up. I guess my question is whether it could be the CDI or if it is in fact the coil. I'm stumped because it is just being like this on the bottom end. If you revv it up a little and get it into the band it wakes right up. I changed pilot jets and it didn't have any affect on it. Raised and lowered the needles and it didn't have any affect on it. PLEASE HELP- I'm trying to go riding this coming weekend.

 

Any ideas of what to try next?

 

Left side pilot jet is clogged. Typical on a banshee due to the small size of the pilot hole.

 

I agree with alky it sounds like the Left side pilot jet is clogged. My banshee did that all the time. If it sat for a week or two one
of my pilot jets would have this yellowish white stuff in it. I got so good at cleaning pilot jets i can do booth sides in 15 min.
The whole prob was the gas i was using. I use 92 unoxygenated gas and no more problems.