The economic miracle of the 1950s and the motorcycle boom in Germany were followed by a collapse in the market in the 1960s. Numerous well-known motorcycle companies disappeared from the market, however BMW stayed true to the motorcycle trade. The relocation of production to Berlin proved to be a very wise move and marked the start of a new success story in the shape of the BMW /5 series in 1969.

figure a

1960 BMW R 27 with Steib S 250 sidecar

figure b

1966 Motorcycle production begins in the Berlin plant with the BMW R 50/2 and BMW R 60/2

Already by the second half of the 1950s, the motorcycle market had become significantly weaker, as more and more people turned to the car as their preferred mode of transport. As a result of this weakening in demand, even wellknown brands such as DKW and NSU were driven to produce almost only cars and hardly any motorcycles in the 1960s. Many other brands concentrated on the production of 50-cc machines, such as mopeds and scooters, which were still in demand. During this time, BMW AG also focused heavily on automobile production.

In Munich, people concentrated on the further development of the existing models and the continued challenges of the racing disciplines. When it came to the single-cylinder models, the R 26 became the R 27, which was significantly optimised in terms of comfort. Thus, the entire drivetrain and the exhaust system was given a rubber-cushioned mounting bracket in silent blocks, reducing vibrations to a minimum. At the same time, output was increased from a previous 11 kW (15 hp) to 13 kW (18 hp). Singlecylinder production was finally discontinued in 1966.

figure c

1960 BMW R 69 S

figure d

1969 BMW R 75/5

Among the Boxer models, the R 50/2 and the R 60/2 made their debut in 1960, both of them close cousins of their direct predecessors, the R 50 and R 60 from the 1950s. The reworking of the engine of the R 60/2 brought an added 1 kW (2 hp) of power. 22 kW (30 hp) now offered a top speed of 150 km/h. Increased reliability was assured by a new crankshaft and camshaft and well as a frame reinforced with gusset plates.

BMW Motorrad launched two attractive sports models in autumn 1960 in the shape of the R 50 S and R 69 S. While the 500-cc engine produced 26 kW (35 hp) and 160 km/h, the 31 kW (42 hp) of the R 69 S achieved a remarkable maximum speed of 175 km/h. As well as significantly improved riding dynamics, the two S models were also the first to have a hydraulic steering damper, quietening the front of the bike on poor road surfaces in particular. By this time, the significantly more comfortable seat that had replaced the previous sprung saddle had become a permanent fixture.

Several racing successes also ensured that the sporting image of the R 69 S remained intact. Examples included the twin victory in the Bol d’Or, the Montlhéry 24-hour race, or the 12 and 24-hour world records.

A massive restructuring project began at BMW AG in 1965. The plan was to concentrate automobile production in the Munich and Dingolfing plants, while motorcycle production was to be moved to Berlin-Spandau. Thus, at the beginning of the 1960s, BMW motorcycle chassis were already produced in Berlin. Final assembly took place here from 1966 onwards, while the relocation of production was completed by 1969, although development and road testing still remain in Munich to this day.

Positive signs from the American motorcycle market seemed to provide some light at the end of the tunnel and the motorcycle industry once more enjoyed better times. BMW Motorrad launched a completely new series in autumn 1969, just in time to catch the wave. A completely newly developed engine and a new chassis were part of the design: The legendary /5 series was born. The new model range encompassed the 24 kW (32 hp) R 50/5 and the powerful 29 kW (40 hp) R 60/5, as well as the top model, the R 75/5 with an impressive 37 kW (50 hp) and a top speed of 175 km/h.

In design terms there was almost no sign of the old Boxer engines. The crankshaft — no longer pressed from individual segments, but forged in a single piece — now moved on plain bearings and the camshaft was positioned under the crankshaft. As before, a tunnel design was used for the engine housing, however this was significantly more rigid than before and offered plenty of room for a larger capacity engine. Stability was also provided by the alloy cylinders with cast cylinder liners, which were held in place by four tensioning bolts, as well as the additional two-way screw joint of the cylinder heads. Carburetion was performed on the R 75/5 by a constant pressure carburettor instead of the old slide carburettor, which was associated with improvements in throttle response and homogeneous acceleration. On the chassis side, the company puts its faith in a new double-loop steel tubular frame and a swing arm with two oil pressure spring struts to the rear and a hydraulically damped telescopic fork to the front. Long spring deflections, much greater ground clearance and the easy handling of the new BMW models drew praise from all sides.