In the late Sixties, the American Motorcycle Association lifted displacement capacity for OHV engines to 750cc. This happened to coincide with Harley-Davidson’s release of their OHV 750, the XR. Trackmaster was an American company that had been building specialty frames for dirt tracking since the early Sixties. They were a generic frame and most any engine could be installed. They offered an oil in frame option and quicker steering with an adjustable steering angle. This is a great example of “the way they were". A small one-gallon fiberglass tank sits atop a parallel Triumph twin engine, probably bored to 750cc. Rare ARD magneto with fixed advance. The pipes exit on the right-hand side. The gearshift and brake lever are also on that side. The brake is a Hurst early disc unit, favored by riders then. Fitted with replacement cases. This was the type of bike that Gene Romero and Gary Nixon rode to victories on American dirt tracks.