The R27’s 250 cc OHV vertical single was the only rubber-mounted thumper engine BMW ever produced, and was theirlast shaft drive single-cylinder motorcycle. The engine developped 18 hp (13 kW), the highest ever for a shaft-drive BMW single. BMW manufactured 15,364 R27 models (engine numbers 372 001 – 387 566 ) over the production years of 1960 to 1966. BMW did things differently from other manufacturers.
This is evident in the R27. Its enclosed shaft final drive is rare for a single cylinder motorcycle. But it also had a triangulated Earles front fork (named after English designer Ernest Earles);
so the motorcycle had a front swingarm as well as a rear swingarm. When you squeezed the front brake lever hard not only did the front end not dive, it actually rose slightly.
Thus, braking was a very steady activity, though the brakes were weak by today’s standards. The engines crankshaft was laid out fore-to-aft, not side- to-side; also a rare feature.
This way, the crank and the final shaft were in line, and drive forces did not have to be run through a set of 90-degree gears. Also, the kick starter swung out sideways instead of parallel to the frame, so kick starting an R27 is a rather easy and danger-free affair. This 1963 BMW R27 with a Steib 200LS sidecar, is a well running, older restoration.
Report by yesterdays.nl