I have been working on this new to me quad for a while nox. I put a K&N air filter in it and I was told I needed a bigger jet because it was bogging down on the top end. I installed the new jet and cleaned the carb and got it all back together.

It started to backfire and the plug was black so I adjusted the needle up one spot to cut the fuel down.

Now the idle is all over the place and its still ideling rough,lots of smoke and just not right.

I tried the rev bypass but it didnt do anything. I unplugged the black wire from the CDI box and it seems to have cured all of the problems. Runs much smoother but the idle is a little high. No more backfires and just sounds and feels alot better. DOes this mean the CDI box is bad or could it be another problem?

Thanks for any help!

 

i would try checkin the kill switch assembly to see if its dirty or corroded. also check for any bare spots in the wiring. all it takes is that black wire to ground out to start causing problems