Only Honda could have done the oval-piston NR, says Hirano and he's right of course. Even after two decades, the NR represents unsurpassed engineering brilliance...
Honda produced just 300 units of the NR and that was back in 1992 – more than two decades ago – and yet, for us, that bike remains one of the most intriguing, deeply fascinating motorcycles ever built anywhere in the world. Some of that fascination is down to the NR’s oval-piston engine, of course – the NR’s massively complicated four-cylinder 750cc engine had 8 valves per cylinder and two conrods per piston, which allowed the engine to function as a V8. No, honestly, we don’t really understand how it worked, but the fact that it did, and that Honda actually built a streetbike – one that cost US$50,000 back in 1992 – around this engine was some kind of a miracle. And it really doesn’t matter that with 125bhp at 14,000rpm, the NR engine’s output doesn’t really look anything special today, when compared to modern-day 750cc sportsbikes.
“When I look back at it, I’m not sure if we were experimenting with cutting-edge technology or obsessed with foolish ideas,” says Toshimitsu Yoshimura, speaking to Inspire magazine. “We didn’t think much about whether the engine would actually turn over or even whether it would be practical at all. We weren’t worried about those things since we just wanted to make it work. To create anything, you must put your heart and soul to it. The development of oval piston engines impressed that upon me, as well as on the other young engineers,” adds Toshimitsu, who was one of the engineers who actually worked on the development of the Honda NR’s oval-piston engine.
