I have a full HMF exhaust on my Raptor and the dyno jet kit. if I wanted to put stock head pipe back on and goin with another slip-on would I have to rejet again or what?

 

most likley yes. tell your silencer mfg what you have and ask for a recomindation then put a new plug in it , ride it & check your plug & rejet if necessary as mfg recomindations are usally just a good starting point. Any time you change your air flow you must rejet!

 

If you are just changing from one manufacturer to the next, you will not need to rejet, and the headpipe make no difference in jetting