Ok so I'm one of the newest members to the site. Hi everyone. It's been a while since I've been in the dirt and I am not real familiar with XRs, but I'm picking up an 89 for $500. It runs good and is in fair condition considering the age so it should be a good ride. I've been looking through some accessory suppliers and noticed that most of the exhausts available are for 85-87 and 91 and up. What's the deal, why are the 88-90 models left out? Is there some reason the 88-90 models are unique?