Picture story: Honda's oval-pistoned 1979 '0X' NR500
This is Honda's oval-pistoned 1979 '0X' NR500 engine, with which they would re-enter GP racing after a twelve years hiatus. The oval piston was Honda's solution to the problem of making a 500cc four-stroke competitive with the contemporary 120bhp, 500cc two-strokes: twice as many valves, twice the intake efficiency, twice the revs. It would be an interesting ride.
"When I look back at it, I'm not sure if we were experimenting with cutting-edge technologies or obsessed with foolish ideas," says Toshimitsu Yoshimura, an engineer involved in the development of the engine. "At least we were doing something that was beyond the realm of conventional thinking."
Amen to that.