Among four new models introduced in 1938 was the one that represents BMW’s overhead-valve sports roadster in its ultimate, pre-war form – the R66. Intended as a sporting sidecar mount, the latter joined the existing ohv 500, now typed ‘R51’, but did not feature the smaller model’s two chain-driven camshafts, using instead the single gear-driven camshaft of the sidevalve-engined twins. This new engine went into the updated cycle parts introduced at the same time, which featured a telescopic front fork and plunger rear suspension. Although the sprung frame resulted in the R66 weighing more than its un-sprung predecessors - 187kgs (412lbs) - the exemplary power output of 30bhp more than made up for the increase, endowing the bike with the top speed slightly in excess of 90mph. In total, 1,669 were made between 1938 and 1941. One of the most modern and capable of all pre-war roadsters, the rare and desirable R66 is today highly sought after by BMW collectors. After many years of searching for an example, Professor Ehn purchased this R66 for the Museum in 1993. In poor condition when acquired, the machine was sent to HP-Moto in Znaim for a complete mechanical and cosmetic restoration. The latter was completed in 1995, and after extensive road testing the R66 was placed in display in the Museum. The machine is offered with Austrian Typenschein.