Honda had temporarily retreated from World GP racing in 1967, and returned after a decade-long hiatus, in 1979.
Honda had developed the 4-stroke NR500 to compete in the 500cc class, which was at the time dominated by 2-stroke machines. This dominance was indeed Honda’s motivation to fight for the title with a 4-stroke machine. The biggest issue at the beginning, was power. For a 4-stroke engine to produce power equal to a 2-stroke, it would in essence need twice the revs. 4-stroke engines were more complicated than 2-strokes, and were thus larger, and heavier. Miniaturization of the engine was a major challenge in winning grands prix.
Honda’s engineers first considered a V-8 engine: A 32-valve V-8 engine with 32.5cc cylinders would be able to produce the same power as rivals’ machines. World GP regulations, however, limited the number of cylinders to four, so the V-8 was out of the question. The engineers, keeping the basic structure of the V-8, decided to merge pairs of cylinders, giving birth to the oval piston engine. This new, unheard-of V-4 engine, powered the NR500.
Development of a radically new engine demanded endless trial and error procedures, but in the end, although the engine was less powerful than first planned, was completed. The engine was paired with a chassis brimming with Honda’s innovative technologies, such as an aluminum monocoque frame, 16-inch tires, coaxially-mounted drive sprocket and swing arm, and multi-component Com-Star wheels. The NR500 entered World GP racing as the epitome of Honda’s challenging spirit.
The NR500 first appeared in August, 1979 at the British Grand Prix, but retired soon after the race began, owing to insufficient development and testing. The grands prix that followed were ideal testing grounds for the NR500 which was continuously improved. In the 1980 season, the NR500 entered 3 races and finished 2, in 15th and 12th places. In 1981, the NR500 raced 6 grands prix, and finished one in 13th place.
For three years the NR500 failed to win, but the technologies and experiences Honda accumulated during this time were invaluable, and were undoubtedly a major contributing factor to the success of the NS500 which appeared in 1982.