I just put a set on my 2005 S2R 803, no need to remap if running stock mufflers. If you get them, lossein your header pipes so than can move alittle, as slipping the mid-pipe on I found that I had to do this as they "just' don't line up, but once loose it was easy. You may need to put some exhaust goo to help seal it, may or may not??