1974 BMW R75/6
With an experienced team and a lot of data.
You could distinguish the BMW R75/6 from the larger, companion R90/6 by the labeling on the crankcase and side cover. Otherwise, unless you looked at fuel consumption—which was slightly less at 49 mpg—it was approximately the same long-striding, comfortable, quiet motorcycle. This sixth-generation bike now adopted a five-speed gearbox, stronger 280-watt alternator, and front disc brake with single-piston caliper mounted behind the fork to reduce distortion during hard braking. A hydraulic steering damper was adjusted by turning the plastic knob atop the fork. The previous /5 series still had the speedometer integrated into the headlamp nacelle, but now the separate speedo and tachometer were mounted at the short, slightly rising handlebar.
A twin-cradle frame supported the air-cooled, overhead-valve horizontally opposed 745cc twin, which had a bore and stroke of 82.0 x 70.6 and 9.0:1 compression ratio. A pair of 32mm Bing constant-velocity carburetors fed the combustion chambers. The 1974 BMW R75/6 produced 50hp at 6,200 rpm, could rise up and conquer the quarter-mile in 13.5 seconds at 96 mph, and nudged past 100 mph on a longer straight. More than anything, though, the engine’s broad powerband was most notable, especially with the five-speed gearbox. And handling was confidence-inspiring. Early models had a kickstarter, but before long it was deleted as standard. BMW had finally learned the value of color, and the buyer could choose an R75/6 in one of seven available, although black was of course still one of them.