The year was 1970. Harley-Davidson, the sole surviving American motorcycle manufacturer, was sinking under pressure from Japanese imports. To survive, the privately owned company had become part of recreation conglomerate AMF.
In an era when the Japanese were releasing the first generation of multi-cylinder Superbikes, the Motor Company decided it needed to do something dramatic to restore its performance image. And that something turned out to be an assault on the motorcycle land-speed record.
Harley’s race team manager, Dick O’Brien, set out for the Bonneville Salt Flats with this machine, designed and built by Denis Manning. Shaped like a torpedo, the Harley streamliner was just 23 inches in diameter, with a wheelbase over 10 feet.
The rider, Harley road racer Cal Rayborn, couldn’t even see out the front of the machine. The plan called for him to navigate by running next to the center line of the course, which he could follow by looking out the side window.
Don Vesco, the first man on the salt during a week of record attempts, put pressure on the Harley team when he rode a streamliner powered by two Yamaha 350cc two-stroke racing engines to a two-way average of 251.924 mph, setting a world record.
During his practice runs, Rayborn achieved nearly 170 mph with a standard Sportster engine burning gasoline. Then the Harley crew pulled out all the stops, installing a Warner Riley-built, nitromethane-burning, Sportster-based “Godzilla” engine.
Rayborn went 266 on his outgoing run, then turned around and went 264 in the opposite direction despite a broken valve seat that caused the engine to fail 200 feet before the end of the course. The result was a two-way average of 265.492 mph, and a world record that would stand until 1975.
That year, Vesco upped the mark to 302.66 mph in a Yamaha-powered machine. In 1978, Vesco went 318.598 mph in a twin-engine Kawasaki streamliner. But in 1990, the Harley brand took back the record, with Dave Campos running 322.150 mph in an Easyriders magazine-sponsored streamliner powered by two Harley engines. Fifteen years later, that record still stands.
The historic 1970 Harley streamliner that was, for five years, the fastest motorcycle on Earth, has been on display as part of the “Heroes of Harley-Davidson” exhibit presented by Progressive Motorcycle Insurance in the Motorcycle Hall of Fame Museum at AMA headquarters in Pickerington, Ohio.