Milan—As part of BMW’s run-up to next year’s 90th anniversary of the company’s “boxer” engine concept, Stephan Schaller, president of BMW Motorrad, had one of the original 1923 R-32s, excellently restored, ridden onto the gleaming white pavilion from which he was speaking at EICMA.
At the time of this engine’s introduction, its full enclosure of all moving parts was hailed as revolutionary. In place of the primary and secondary chain drives that were messily usual in motorcycles, designer Max Friz gave it unit construction, joining the flat-Twin engine and its clutch and gearbox in a rational single unit. Drive to the rear wheel was by shaft and bevel gearing.
After the customary rock-music intro (with three percussionists raising their hands over their heads to increase the drama of their drumming, plus vocal and guitar) and the conclusion of Herr Schaller’s remarks, I walked to the R-32 and looked at it in detail. This engine is pleasing to look at, many parts being well-executed castings in Silumin aluminum alloy. The footboards are castings, and so are elements of the rear wheel’s final-drive housing.
The rear brake reveals the age in which it was conceived, as it presses a v-shaped block of friction material into what was then called a “belt rim.” Many an Isle of Man TT racer of the early 1920s carried such a rear brake. I tried my toe on the lever. Up front was an internal-expanding shoe brake, a concept that would take other makers some time to adopt.
Everything is clear on such early bikes, and their style arises from the way in which their parts are made and joined. It’s rewarding to have a look at such a machine to refresh one’s appreciation of all of a motorcycle’s functions.