My 99 banshee was running fine unstill it started to break up near full throttle or underload at high r's in 6th gear. It slowly started to infect 5th gear and so on. I changed the plugs and it worked fine for about 15 minutes but then did the same thing and eventually quit all together. I could start it and get going but eventully it would quit. GOt back to the shop took a compression test and revealed 144 and 146 which is fair enough for me. I am going to start by cleaning the carbs and tank and then possibly addressing spark plug wire and grounding issues...any advice?

 

Compression sounds good enough. What did the sparkplugs look like?

 

They were a little darker then a malt brown. Almost black but not quite.

 

What does the spark look like when you kick it over and put the plug up against the cylinder head??

 

It is pretty bright. But i have had a problem with my snopro not producing enough spark once it is all bolted up and ready to run. Changed the wires and it ran fine. i hope it is just the wires on the banshee. I think it could possibly be brighter but i have not had much experience with a baanshee to know exactly what the spark should look like at max potentional. With in the next couple days i will check readings on plug caps, coil and stator

 

Is it possible your jetting is off??

Is the airfilter clean??

Either one of those things will cause you to foul plugs.

 

The air filter was dirty. I cleaned it but then i never got around to taking it for a ride. The weather got nice for a day so i had to take the opportunity and paint my truck with low levels of moisture.

 

I would say throw in a set of new (properly gapped) sparkplugs and take it for a ride and see how it does. Don't assume that because a plug is new, that it is also properly gapped.

If it still dies on you, check the jetting by doing a proper plug check at 1/2 and full throttle with fresh white new plugs. If that checks out ok, I'd be looking at the electrical at that point.

 

Yeah the other plugs were gapped but i still haven't had a chance to try it. I never gave the air filter much thought but i did clean it. It is a uni filter and i had some kn stuff from my bike, so i cleaned it. I will also do the jet check jsut to be sure. I rebuilt the engine in July and it ran flawlessly every time untill two days ago so i guess the air filter is possibly the culprit

 

2-strokes and Banshees in particular are pretty picky about jetting.

Temperature, elevation, and many other variables can cause you to have to re-jet.

Did you say you are using K&N oil on your UNI filter?? I hope not!