1928 BMW R57
Frame no. 22953
Engine no. 70393
* The BMW R57 is historically significant
* From the Gerhard Schnuerer Collection
* Museum-like condition
Following the collapse of its aero engine business after WWI, BMW turned to other areas of manufacture, motorcycles among them. Its first two models, marketed as the Frink and Helios respectively, were failures, but a successful proprietary engine was supplied to other manufacturers. Launched in 1923, the first motorcycle to be sold as a BMW - the R32 - featured a 493cc, twin-cylinder, sidevalve engine having horizontally opposed cylinders, and this 'flat twin' layout would forever be associated with the marque. Setting a pattern that endures to this day, the first BMW motorcycle was relatively expensive but superbly engineered and constructed, while the quality of finish was of the highest order. BMW's first sports machine, the R37, appeared in 1924. The R37 boasted an overhead-valve engine producing almost double the R32's power output, and in tuned form proved good enough to take the German national championship in its debut year.
Before long BMW updated its original tourer, which in 1926 became the R42, gaining a redesigned and more powerful engine boasting detachable alloy cylinder heads and cooling fins set at 90 degrees to the cylinder axis. The engine was set further back in the duplex loop frame, which improved weight distribution and enabled straight front down-tubes to be used. The braking too came in for attention: the old block-and-pulley type rear brake being replaced by a drum on the driveshaft gripped by external contracting bands. In 1927 this same chassis was used for the new R47 sports roadster, which now featured cast-iron barrels in place of the R37's steel items.
For 1928 BMW reorganised its range of engines, which now included a brace of 750s: one sidevalve, the other overhead-valve. A stroke of 78mm was used for the sidevalves and 68mm for the OHVs regardless of capacity, with different cylinder bore sizes depending on the model. Thus, the new overhead-valve R57 sports bike's engine was a 'square' unit of 68x68mm bore/stroke. Electric lighting, hitherto regarded as an 'extra', was standardised throughout the roadster range. R57 production lasted for only three years and today this rare vintage BMW is among the marque's most desirable and sought-after machines of the period.
This BMW R57 is part of the stunning Gerhard Schnuerer Collection and just like any vehicle from that collection, the bike was taken care of as a museum piece, serviced, maintained and kept to the highest standard possible. A large history file retracing the bike's history up until the late-1990s and various correspondences between Mr. Schnuerer and BMW specialist will be handed to the buyer after the sale.
Saleroom notices
- Please note the title is in transit.