I have read simmilar issues on the 750 doing this but i bought a 2006 bf650 yesterday, and it is doing the same thing at an even speed just above idle it will pop back through the air box and has a hesatation from a dead stop, this is very anoying[img]i/expressions/face-icon-small-disgusted.gif[/img][img]i/expressions/face-icon-small-frown.gif[/img][img]i/expressions/face-icon-small-blush.gif[/img][img]i/expressions/face-icon-small-wink.gif[/img][img]i/expressions/face-icon-small-disgusted.gif[/img] for a new quad, does anyone else have this problem with there bf650, if so have you fixed the problem??? My guess it needs to be richend up a little because if you choke it a little it will haul *** from a dead stop, but it looks like to me that Kawasaki has sealed up the air screw holes, any help whould be great, thanks