Denis Manning is a self-taught Engineer, Designer and Fabricator, renowned for his contributions to the world of motorcycle land-speed Racing. He has devoted his life to the pursuit of ultimate speed and his innovative streamliners have succeeded on more than one occasion. Manning's streamliner, piloted by multi-time AMA Grand National Champion Chris Carr, set a world-record speed of 350.8 mph at the Bonneville Salt Flats on September 7, 2006.
This was not the first time a Manning-designed streamliner was the fastest motorcycle in the world. In 1970, Harley-Davidson racing chief Dick O’Brien gathered a team to attempt to break the motorcycle world land speed record. The team included Cal Rayborn as the rider, Clyde Denzer and John Pohland of the H-D racing department staff, engine builder Warner Riley, fuel specialist George Smith Sr., and a young, self-taught designer and fabricator named Denis Manning.
Manning was a fan of land speed racing from a young age, inspired by the legendary Mickey Thompson and his four-engine land speed record car, Challenger. After gaining experience in road and drag racing, Manning focused on the design and fabrication of land speed record streamliners. The machine that Harley-Davidson used in 1970 was Manning's second liner, built on the garage floor of his duplex. In the fall of 1970, Manning piloted it to a one-way speed of 187 mph with a stock Sportster engine running on gasoline.
When Harley-Davidson scouts at Bonneville reported the event to O'Brien, he saw the potential in Manning's design and offered him a performance-based deal to be part of an official Harley-Davidson effort. O'Brien wanted Manning for his expertise in designing and setting up a streamliner, not as a pilot, and chose Cal Rayborn, who was popular and well-known, despite having no Bonneville experience.
Manning agreed to the deal and helped construct a 15-foot-long streamliner, designed to fit his own physique. However, the passenger compartment had to be modified to accommodate the shorter Rayborn. The main structural unit was an aluminum tube with a cross-section of only 23 inches, with aluminum bulkheads riveted into each end. The front bulkhead carried the front wheel, suspension, and steering mechanism, while the rear bulkhead contained the engine, drivetrain, fuel tank, air bottle, and drag chute.
The pilot lies prone, looking out plexiglass windows on either side of the shell. There are also plexiglass windows in the nose, but they are obscured by the front wheel and the rider’s knees. Manning's design aimed for the smallest frontal area possible, to reduce air resistance at high speeds.
Cal Rayborn struggled to control the liner at first and crashed several times before mastering the machine. On one occasion, he sent it into an end-over-end tumble, but thanks to the structural integrity of Manning's chassis, Rayborn was not injured and the machine was reparable. Eventually, Warner Riley and George Smith, both experienced at Bonneville, installed the "Godzilla" engine, an 89-cubic-inch Sportster-based monster fueled by 70 percent nitromethane. With this engine, Rayborn achieved a two-way average speed of 265.492 mph, breaking a previous record held by Don Vesco, solidifying Harley-Davidson's claim as "Number One".
Denis Manning is a renowned motorcycle builder and racer, who has dedicated his life to the pursuit of speed and excellence on two wheels. Despite the challenges and setbacks he has faced along the way, he remains actively focused on achieving the title of the world's fastest motorcycle. With his relentless determination and passion for the sport, he continues to push the boundaries of what is possible on a motorcycle, inspiring others to follow in his footsteps and strive for greatness in their own pursuits.
