What's What? H-D Race Bikes  KR and XLR Manuals XR 750 and XRTT Manuals Technical info on KR and XLR Technical info on XR and XRTT Technical info on KR Cams  WR KR Parts List, 1952/57 Ancestors 1 2 3 4 5 6 "KR style" Twin Carb Manifold Other H-D racers Harley-Davidson Patents   questions and answers... KR and XLR Gear ratios 1, 2, 3 and 4 Gearbox Part Numbers