I have a jetting question. I have recently acquired a 98 sport 400. I've put a K & N filter on it and am about to put a fmf gnarly torque pipe on it also. Will I have to rejet? What size main jet is on it now? Any help would be appreciated.

 

My brother has a 99 400 sport. His main jet was a 230 and according to our shop manual thats what yours is. Your new pipe should come with a new jet or at least some kind of recommendation.

JIM 99TB WITH MANY MODS!!!!!!!!!!!!!!!!!!!!!!