My Raptor has a 686 bore 11.1 piston from JE and a hot cams stage two cam K&N air filter with air box lid off and a full DMC exhaust and soon to be ported head. What size front and rear sprokets should a run? I am trying to make sure i smoke my friends predator and DS 650 in acceleration and top end!!

 

With that setup you shouldnt have any problem, but you could definately go to a 14 front tooth and still have plenty on the bottom to beat them out the hole

 

I am using 14 tooth front sproket on mine and love it.

I agree with KJMAXXX[img]i/expressions/face-icon-small-smile.gif[/img]