jetting yoshimura exhaust

[raptor199]

I bought a yoshimura complete exhaust system for my raptor and ordered an fmf power up jet kit. I got the pipe in and it said if you don't mod your air box lid leave jetting stock. Is that right. I thought you would need to change your jetting for just a pipe.

[trx400exxracer]

yoshimura claims on most of their pipes that you dont have to rejet or modify the airbox but I think you should take the lid off get a uni airfilter and go up a couple sizes with jetting just experiment with different jets until you get the best performance out of the jetting

[raptor199]

I got the pipe on and left the jetting stock. It seems to run good. Do you see anything wrong with running it like this.
thanks

[trx400exxracer]

no I dont, my yoshimura sponsor rep told me you could put it on there and not jet it but I would put an aftermarket filter on it:D