If it hadn't been for the Versailles Armistice Treaty following Word War I, Ewan and Charley would have had to do their glove-trotting on another make of motorcycle. It was the terms of the post-war treaty that forbade BMW (Bayerische Motoren Werke) to make any more aircraft engines, forcing the firm to consider branching out into motorcycle production.
BMW was created in 1916 by the merging of two existing aircraft engine-producing companies, BFW (Bayerische Flugzeug Werke) and Rapp, and following the restrictions imposed by the treaty, the firm started making motorcycle engines for various German manufacturers including Victoria and Bison. By 1923, BMW had built its first complete motorcycle, the 500cc R23 horizontal twin, which was the creation of aircraft designer Max Friz who grudgingly completed the job despite his heart lying in aircraft engines. The motorcycle set many trends that the firm still follows today, most notably the 'flat-twin' 'boxer' engine configuration which was, actually based on the British-build Douglas twin of the time.
BMW's roots in aircraft manufacture are supposedly reflected in its famous logo which, some say, depicts a spinning propeller against a blue sky. But company itself claim the blue and white emblem simply represents the colors of the free state of Bavaria. Whatever the case, when war broke out again in 1939, BMW once again turned its hand to making aircraft engines, this time for the Luftwaffe, including the 003 engine for the world's first jet fighter, the Messerschmitt ME262.