Motorcycle specifications BMWR75/5 1969 BMW changes register

At the end of the 60s, as the motorcycle world entered the modern era with the arrival in force of Japanese manufacturers, BMW took a bold gamble. In 1969, the German company launched its all-new "/5" range a series of machines that not only updated previous models, but completely reinvented them. At the pinnacle of this new dynasty was the R75/5, a 745 cm3 model that would not only save BMW's motorcycle division, but also define its mechanical engineering for the next 25 years.

A new beginning in a new place

For years, BMW had built a reputation for sturdy, reliable but somewhat austere motorcycles, often associated with sidecars and pre-war design. The /5 series was designed to shatter this image.

This radical change coincided with a strategic move. Motorcycle production was transferred from the main factory in Munich to a new facility in Spandau, West Berlin. This fresh start gave the engineers the opportunity to start from scratch.

The objective was clear: to target the fast-growing American market, which demanded power, style and modern equipment. The /5 series - comprising the R50/5 (500 cm3), R60/5 (600 cm3) and R75/5 (750 cm3) - was BMW's answer.

A complete technical overhaul

The R75/5 was not a simple evolution; it was a complete overhaul. The most significant change was at the heart of the machine: the type 247 flat-twin boxer engine.

Although it retained the iconic boxer configuration, almost all the internal components were new:

• Modernized bottom end: engineers abandoned the old crankshaft roller bearings in favor of modern, automotive-style plain bearings, more durable at high rpm.
• Redesigned camshaft: The camshaft was moved from above to below the crankshaft. This ingenious change lowers the bike's center of gravity and leaves room under the fuel tank for the new electric starter.
• Electrical equipment: the R75/5 was the first BMW to be fitted with a Bosch electric starter as standard. It also switched from an obsolete 6-volt electrical system to a modern 12-volt system, capable of powering more powerful headlights and indicators.
• Carburation: Fuel for the 745 cm3 engine was supplied by a pair of Bing constant vacuum carburetors, offering smooth, linear throttle response.

The chassis was also completely modernized. The old Earles-type front fork, designed for sidecar stability, was replaced by a modern telescopic fork. The frame itself was a new double-loop tubular steel design, often compared to Norton's famous "Featherbed" frame for its rigidity and handling.

Power meets comfort

As a flagship model, the R75/5 offered very respectable performance for its time. Its 745 cm3 engine produced 50 horsepower at 6,200 rpm, propelling it to a top speed of 175 km/h. But the Behemoth was no match for the Honda CB 750 Four, which arrived at the same time and redefined all standards.

But the R75/5 was in a different league. It was a sophisticated touring bike. The boxer engine offered perfect balance, minimizing vibrations, and the final drive shaft was clean and low-maintenance.

Breaking with the "always black" tradition, /5 models were available in a range of bright colors, visually signaling the brand's new direction.

A total of 38,370 units of the R75/5 were produced between 1969 and 1973. It represents a turning point in BMW's history, when the brand took an important step towards modernity.

M.Bi. - Manufacturer photos