About the Honda NR 750
In 1979, 500cc motorcycle racing was dominated by 2-stroke machines. Honda introduced the NR500 4-stroke racer that year, in an attempt to break this 2-stroke hold on 500cc Grand Prix Championships. Honda's bike had an epoch-making aluminum monocoque frame, 16-inch wheels, and was powered by a 32-valve, V-4 cylinder engine using oval-pistons. Each cylinder had 8-valves and two spark-plugs that enabled it to turn at an astonishing 20,000rpm, and producing horsepower equivalent to a 2-stroke engine.