had a bad cam...replaced entire head on my 96 500 with an 02 500HO head, new cam, rockers, valves, etc.. It fires right up now but wont do more than 10mph max.....acts as though its starving for gas or the timing is off?? Acts like it wants to back fire but never really does. I have confirmed timing is 110%!! Carb is 110% clean. Think I should throw bigger jets in there?? Im at a loss and not sure what else to try??? New stator, CDI, HEAD, cam, rockers, valves, etc...

 

Did you put a bigger carb on yet? You need a 40mm instead of the 32mm.

 

Raise the jet needle and see if that helps.