I have put a carb kit in my 1996 300 KQuad because it wouldn't idle. After the install, the bike would rev up then down on idle. I figured air leak. I replaced the plastic boot, gasket, and o-ring on the machine intake side due to a small crack. It has since gotten worse. It lacks power and is back firing now. Compression is 135psi, no leaks, the misture appears good, a visual by the plug. I installed a inline high flow fuel filter. I am stumped. is it possible that the timing could be off. I set the main jet 1 1/4 turn. any thoughts on this matter you help pls.

Jay

 

is the idle screw adjusted correctly?