I have a 1999 banshee , rode it yesterday and it ran fine. Went to ride it today and it was running terrible. the bike would only run with the choke pulled half way out. when you push the choke all the way in it wont idle and it wont run smooth. the only modification to the bike are k&n filter and two 1/2 inch holes drilled in the top of the air box. It acts as if it was starving for gas so i pulled the fuel line and the flow was fine. I also changed the plugs thinking that might be it but it was still the same. I did let someone ride it yesterday for a few minutes and they rode it pretty hard. the guy thought that it had a rev limiter on it like his 400ex has, so he ran it at very high rpms(wide open) for about 10 seconds at a time without shifting. it was smoking quite a bit but when he stopped and i rode it it stopped smoking. Could he have damaged it? or is it just coincedence. do i have something in the carbs? dirt ect. reeds? any input will be helpful....thanks. I should also add that someone removed the spark arrestors or baffles out of the stock pipes. teebone

 

if it is colder today than yesterday it could be jetting