I race the old "sh*t" with AHRMA. A 1980 KZ750 that me, Pete Hockenstad, and Carl Schwenz built. And a beautifully prepared 1973 xs650/750 yamaha. When I do go to modern races with them they get A LOT of attention. I race the KZ in the modern classes against sv650's. Last year I ran 2.07's with it at HPR. It's pretty modified. The xs is really just fun to look at and listen to when it's running wide open down the straights. An sv650 will kill it.