Stock Stories: 1960–69 BMW R69S
With custom bike culture exploding in recent years, the history and importance of the two-wheeled machines that first rolled off of the production line are often overlooked. Stock Stories tells the tales of these motorcycles.
After World War I, a combination of treaties regulating Germany’s manufacturing and military capabilities resulted in the dissolution of the country’s air force and heavy restrictions on aircraft production. In 1922, like many industry workers in search of other projects, BMW head of design Max Friz turned his attention to motorcycles. Also an engineer, his choice of power plant was one that had been used in various motorcycles before: the boxer.
The boxer’s roots can be traced back to 1897, when German engineer Karl Benz built his new four-stroke engine. The design utilized a twin-cylinder, horizontally-opposed setup in which the pistons simultaneously reached both top and bottom dead center. This synchronized motion of the two pistons was likened to two boxers trading blows, hence the nickname.
Benz’s compact and reliable flat engine design would be adapted in various forms throughout the 20th century for applications including aviation, power plants, automobiles, and motorcycles. Initial configurations for motorcycles using the boxer engine mounted the unit with the cylinders running the length of the motorcycle; this arrangement regularly caused the rear cylinder to overheat due to lack of air flow. Friz figured that reorienting the design laterally would solve the overheating issue, turning the engine 90 degrees in order to evenly expose both cylinders to open air. Not only was this insight correct, but a big upside was that implementing direct drive to the rear became a much easier task. With the crankshaft facing the rear of the motorcycle, a shaft drive to the rear wheel permitted clean and smooth transmission of power that improved upon the common chain and sprocket combination.
The first motorcycle made under the BMW brand was the R32, released in 1923. From then onwards the boxer engine and shaft drive combination was continually developed and became a mainstay in BMW motorcycle designs. The boxer engine was so developed that almost four decades later, by 1960, BMW was utilizing a modular system which allowed for various engine sizes to be produced from the one core design.
One such engine was the R69S, a sports variant tuned with 9.5:1 compression and larger inlet ports. Fuel flow was further aided by a larger air filter and a wider-diameter exhaust tip on a less restrictive muffler. Crankcase ventilation was also improved for the S model, courtesy of a rotary-disc ventilator. Combined with closer ratio gears, these various upgrades helped the R69S become the most powerful BMW twin to date, producing 42 hp at 7000 rpm.
Designed as a sports motorcycle with touring capabilities, the S model made for a faster ride while maintaining BMW’s established reputation for reliability. These were appreciated as prestigious motorcycles with smooth, quiet ride characteristics and a high-quality finish. By this time BMW motorcycles also renowned for their touring capabilities, earned through various achievements in both motorsports and long-distance record attempts.
In the 1950s BMW won success with its road racing entries, but by the end of the decade the company was approaching bankruptcy due to the expense of its car production. The situation hit the motorcycle division hard with only 5429 bikes being built in 1957, the majority of which were for export. The U.S. was an important market with a demonstrable need for reliable touring machines, and BMW motorcycles ticked a lot of boxes for American riders.
Various events during this tough period for BMW helped keep up its reputation for durable and reliable motorcycles. In June 1959, John Penton set a new coast-to-coast record, riding 3051 miles from New York City to Los Angeles in 52 hours and 11 minutes on a standard BMW R69. The positive publicity helped BMW proving that its machines were more than capable for American-style touring.
As the company emerged from bankruptcy in the early 1960s, thanks to support from major shareholder Herbert Quandt, BMW switched its motorsports attention from expensive road racing to a relatively more affordable endeavor: off-road sport. BMW entered a Works-modified R69S into both the German Off-Road championships and the infamous International Six Days Trial (ISDT). Ridden by Sebastian Nachtmann, this highly modified R69S won both the 1960 and 1961 German Off-Road Championships. Further success came in the 1960 ISDT, held in Austria, where Nachtmann achieved the highest points out of 300 riders taking part and helped his team achieve third place. The following year when the ISDT came to Llandrindod, Wales, as part of a six-man team, Nachtmann won a gold medal in the over-500cc class with his team winning the international trophy.
London-based motorcycle dealers further touted the versatility of the R69S. MLG was one such outfit, showcasing the capabilities of the sports model on the race track. A considerably modified R69S, sporting a Peel dolphin fairing and with high-compression Mahle pistons and shallow-taper megaphones, to name, this racing special stormed the banked circuit at Montlhéry, just outside of Paris in March of 1961. The special team consisted of four riders: Ellis Boyce, George Catlin, John Holder, and Sid Mizen, who successfully broke the 12- and 24-hour records. England’s Velocette had only just broken the 24-hour record a week earlier, breaking the 100-mph mark with an average of 100.05 mph. The MLG team achieved an average of 109.39 mph over the 12 hours and 109.24 mph over the 24 hours, clocking up 2621.77 miles along the way at 34 mpg. This record remained unbroken for more than a decade, until a Kawasaki Z1 achieved 109.64 mph at Daytona in 1972. The 9 mph BMW added to the Velocette record was thus a significant achievement, and a testament to both MLG’s tuning and nearly 40 years of engineering development by BMW.
Further success in 24-hour racing came in 1960 when René Maucherat and René Vasseur won the Bol d’Or endurance competition at Montlhéry. Peter Darvill and Bruce Daniels just missed out on winning the 1960 24-hour race at Montjuïc in Spain, but BMW later supplied support for the team, which returned in 1961 to win the event (as well as the Silverstone 1000-km race).
BMW motorcycles continued to be used for touring and in endurance sport extensively throughout the 1960s. By the end of the decade, Dutch BMW dealer Henny Van Donkelaar took matters into his own hands by providing customers with bored-out 730cc R60 and R69S machines, using light alloy cylinders from West German specialist Wolfgang Kayser. Some of these machines were used in competition, especially in long-distance trials and sidecar motocross—further testament to the durability of the BMW boxer engine.
Even now, the BMW boxer retains a niche of dedicated fans. Mileage that would be considered low for an R69S would be concerningly high for any other bike of the era, proof that BMW achieved its mission and produced a long-lasting machine with enduring influence.