A Look Back at the Racing Machines of Yesteryear - The NR500 with the elliptical piston started and continued to run
Honda NR Challenge
Adventures of the NR
Part 2 Technical Review
Elemental Technologies of the NR500 that Achieved 250-plus Horsepower per Liter 40 Years Ago
Page 14-15
This document, titled "NR Road Race Project PHASE-1 Propulsion Plan," is a plan of strategy and organizational blueprint that detailed how the NR500 would be developed and operated. It was prepared by Takeo Fukui, who later became Honda's sixth president, and was notified to the project team in November 1978, when the design of the monocoque frame (commonly known as the "shrimp shell" frame) was started. This internal document is completely confidential, but the Racers editorial staff has reproduced it through this interview.
Page 24-25
Honda called the engine with oval pistons (or more accurately, elliptical pistons) "UFO," because it was a DOHC 32-valve (8 valves per cylinder), V-type 4-cylinder, 500 cc engine that needed to rev over 20,000 rpm and produce over 130 horsepower to compete with 2-stroke rivals such as Yamaha and Suzuki. The engine had to rev more than 20,000 rpm and squeeze out more than 130 horsepower. Although this was possible in terms of calculations, the NR project was beset with a variety of difficulties when it came time to begin production. This photo shows the cylinder head of the NR500 (courtesy of Honda).
Page 32-33
Let us take a closer look at the engines of successive NR500s. The first engine is the "0X" engine installed in the first model, development code: NR1, driven by Keisuke Katayama in the British GP in 1979. The page introduces the design drawing obtained from Honda. Its V-bank is 100°. At that time, a shear angle of 100° was still necessary to ensure adequate intake passage while accommodating the NR-specific carburetor unit, which was a combination of a downdraft type for the front bank and a side-draft type for the rear bank.
Publisher : Sanei Shobo (12/26/2019)
Release Date : December 26, 2019
Language : Japanese
Mook : 98 pages