The Harley-Davidson XR-750 dominated American flat-track racing after its introduction in 1970.
Harley-Davidson developed the XR-750 after racing rules changed and the company needed a competitive replacement for the earlier KR racing motorcycle. The first XR-750 used an iron-head engine, while later versions adopted aluminum cylinder heads and became the better-known form of the machine.
The XR-750 became one of the most successful motorcycles in American racing history. Its success was tied to its light, purpose-built design and the specialized demands of dirt-track competition. It was not simply a modified version of a standard Harley-Davidson street bike.
The motorcycle also became culturally recognizable through stunt performer Evel Knievel, who used an XR-750 in many of his jumps. That association sometimes causes people to identify the bike only as a stunt machine, overlooking its extensive professional racing record.