2007 CRF450X - I drained and replaced antifreeze with engine ice. I also installed FMF Power Core 4 slip on last night. Now there is a lot of popping when I let off the throttle. There is a little white smoke while running warm but more when turn bike off. The previous owner had the idle down really low and I tried to adjust but I am not sure if that made it worse. Is there any factory recommendation on the idle screw? Turn all the way (left or right) then turn out so many turns? No other air box or modifications, factory jetting. Any suggestions? I found somewhere the smoke could be antifreeze? Could have I over filled? Running really hot and heating up really fast on idle. Thanks.