It’s easy to imagine any motorcyclist growing up in the 70s fixating on Yamaha RDs. The bikes were fast and ferocious smokers. And their reputation was only enhanced by their close ties to Yamaha’s production racers. The culmination of that history was the 1976 release of the air-cooled, two-stroke twin, the RD350’s bigger brother, the RD400.
More suited to eating up twisty pavement than straight stretches, the RD topped out around 105 mph. It wasn’t the fastest bike down the straights, but it more than made up for it leaning into the corners. The engine and frame, both born and refined on the racetrack, used thicker-wall steel tubing with track-spec geometry. In its day, it represented the pinnacle of design.…