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Development of the BMW engine proceeded rapidly throughout the 1920s, with the first 750cc models, the BMW R62 and R63, arriving in 1928. A side valve tourer, the former employed the same long-stroke (78mm) built-up crankshaft as the new 486cc R52, while the sporting overhead-valve R63 featured a short-stroke (68mm) crank coupled with a 83mm bore. These new engines incorporated a strengthened gearbox featuring a 'side-throw' kickstart, while the cycle parts were upgraded with a larger front brake. Electric lighting was now standard on all BMW models. A spirited performer on the road, the R63 was also raced by the works alongside its 500cc stablemates and, like the latter, pioneered the factory's use of supercharging. Although a relatively modest 75mph maximum was claimed for the stock R63, it was a modified version that provided BMW with the means of securing its first motorcycle land speed record, when Ernst Henne achieved a maximum of 133.8mph on a 'blown' example in 1929.

The arrival of the fashionable 'saddle' fuel tank at the end of the 1920s meant that BMW's distinctive wedge-shaped tank had to go. The resulting wholesale revision of the design undertaken for 1929 would later confer iconic status on these early BMWs, none more so than the R63, which enjoys great historical significance as the Munich firm's first ohv 750 roadster. Approximately 800 were made.