I have tried to do a search on exhaust but haven't found the right answer for a spark arrestor that doesn't cut performance. Is there one? The vortip looks interesting but I don't have a stock exhaust and the guy I got the bike from doesn't what kind of muffler is on there. It looks like a stock YZ. The bike is a '99 WR and I want to dual sport it. Any suggestions on how to identify the muffler. There are no stampings or any marks.