Behind the Birth of the NS500
text=KIYOKAZU IMAI
translation:SHINTARO URASHIMA
"NR" Was at the Vanguard
The background of the birth of Honda's first 2-stroke GP500 road racer
2023 marks the 75th anniversary of the establishment of Honda Motor Co., Ltd. while Honda Racing Corporation (HRC), a subsidiary focusing on motorsports, celebrated its 40th anniversary in 2022.
Since its establishment in 1982, HRC has focused on motorcycle racing right through to 2021.
During that time, the company (HRC) has produced countless racing bikes.
Among them, we will pick up focus on machines that are remembered as epoch-making in particular, and showcase the passion of Honda men who were devoted to their development and racing activities. First of all, we would like to introduce the NS500, which gave Honda its first riders' title in the premier class of the FIM Road Racing World Championship.
This article, "All About Honda Motorcycle Racers Presented by the RACERS magazine" is a digest of "RACERS Vol.01 '83 NS500," including revised contents based on information from subsequent interviews during more than ten years after the first publication.
With the 4-stroke in the pursuit of engineering innovation,
the NR500 didn’t work as intended.
In September 1983, Freddie Spencer riding the Honda NS500 won the championship at the Imola circuit in Italy where the San Marino GP was held. It was Honda's first premier class riders' title in the FIM Road Racing World Championship.
It was in August 1979 that Honda returned to racing in the World Grand Prix after a long absence since 1967. Its top category, 500cc class, was ruled by 2-stroke engines at the time, but Honda re-joined the international scene introducing the NR500 equipped with a 4-stroke engine.
“Win the world championship within three years creating innovative technology." Honda set a higher goal when they planned to return to the race. They chose 4-stroke to "create innovative technology." In order to beat the 2-stroke racers
with the same displacement and the same number of cylinders, you must put in extra effort on the 4-stroke engine because it has half the chance of ignition/explosion as the 2-stroke at the same rpm. Innovative technology was not only an end but also a means. Honda came up with a breakthrough idea of an oval piston/cylinder with 8 valves (in-line 4 intakes/4 exhausts) that could maximize valve-opening area. The unique chassis was also a part of NR500 developed diligently by a group of Honda’s young engineers.
When it came to the actual race, the NR500 faced difficulties. In 1979, it made only two appearances in the World Grand Prix series. The first race of two NR500s at the British GP resulted in two DNFs. In the second race at the French GP, neither of the two bikes qualified. Reflecting those horrible results, Honda went back to a more conservative chassis design for the 1980 model and also its engine was revised including changes in the valve system.
In the second year, the NR500 improved in its durability but the increase in engine weight became an issue considering competition against 2-stroke racers. The best finish in the 1980 season was 12th place at the West German GP.