100 years BMW Motorrad – Still going strong….

2023 was the anniversary of 100 years of BMW Motorrad. The nuclei from which Bayerische Motoren Werke emerged were the small aircraft and aircraft engine manufacturers Rapp and Otto on the north-western outskirts of Munich. Rapp-Motorenwerke was renamed ‘Bayerische Motoren Werke GmbH’ on 20 July 1917. The new company logo depicted a rotating propeller against the background of the white and blue Bavarian state colours.

The designer Max Friz created aircraft engines whose performance set new standards. The lost war dashed hopes of being able to continue to offer the engines. In the early years of the Weimar Republic, BMW lived from brake construction, but also produced vehicle and boat engines, such as the ‘M 2 B 15’ motorbike boxer.

At the end of 1921, the buildings of Bayerische Flugzeug-Werke AG, formerly Otto-Werke, became the new home of BMW. Two motorbikes were taken over as a mortgage: the mini two-stroke ‘Flink’ and the ‘Helios’, a 500cc touring machine with a longitudinally mounted BMW M 2 B 15 engine. Max Friz achieved the stroke of genius for the BMW bike in December 1922: he created a new concept while retaining the M 2 B 15 boxer engine. To this day, it still epitomises BMW motorbikes more than any other design. The R 32 from 1923 had the cylinders at right angles to the direction of travel. The three-speed gearbox was directly connected to this engine and a shaft ran to the rear wheel. The shaft drive was used exclusively by BMW Motorrad until 1993 and, like the boxer engine, became the ‘second trademark’.

Successes, records and good press

In 1925, the young engineer Rudolf Schleicher fitted OHV heads to the previously side-steered R 32. Schleicher and Fritz Roth won a gold and a silver medal at the 1926 Six Days’ Ride in England with the now christened R 37, which earned BMW Motorrad good international press. A new model generation of 750s, with a pressed steel frame surrounding the side of the tank and a pressed steel leaf spring fork, replaced the tubular frame predecessors with a plug-in tank in 1929. In 1931, the BMW motorbike programme was supplemented by the R 2 with 200 cc and the similar single-cylinder mid-range model R 4 with 400 cc displacement in order to achieve large numbers.

The factory had given up road racing. Instead, BMW, represented by the Munich authorised dealer Ernst Henne, launched an attack on the absolute world record. On 19 September 1929, Henne succeeded in breaking the absolute world record to 216.75 km/h with a supercharged 750cc. His last record of 279.5 km/h on 28 November 1937 was to stand for another fourteen years. The BMW 750cc motorcycles underwent a decisive innovation in 1935 with the introduction of the telescopic fork on the front wheel, which was to influence motorbike construction worldwide.

In addition to off-road racing and world record attempts, BMW also became active again in the European Championship in 1935. The following year, BMW stole the show from the competition with the 24 hp OHV-500 R 5. The black machine with tubular frame and telescopic fork was graceful and smooth. Road holding, ride comfort and performance were superior to all other half-litre machines.

In terms of aircraft engines, upgrades and the worldwide spread of air travel had ensured full order books. BMW Motorrad achieved a special sporting triumph in 1939 by winning the Tourist Trophy. Georg Meier was the first continental European to win the 500cc class at the Tourist Trophy on the Isle of Man on a foreign machine.

The Second World War saw BMW grow into a company of European proportions. The piston aircraft engines were supplemented by jet engines from 1943, which brought BMW the interest of foreign secret services at the end of the war.

Dismantling and a new beginning

After the end of the war, BMW was at the top of the dismantling list as an armaments company. The Eisenach plant had fallen to the Soviet Union. The Soviets quickly got the plant up and running again and produced motorbikes and cars for their needs. Munich, on the other hand, was dismantled and for a short time it looked as if BMW would be completely dissolved. They built brake compressors, handcarts, kitchen and garden appliances and a small series of prototype bicycles with light alloy frames. But in 1948, the R 24 appeared as a further development of the 250cc R 23. After the currency reform and the founding of the Federal Republic of Germany, the R 51/2 boxer machine appeared in 1950, a further development of the R 51 from 1938. The constantly further developed 250cc BMWs were among the best-selling machines on the German market in the 1950s and saved the brand with the BMW Isetta. The crowning glory of the motorbike range was the R 68, which was the first production BMW to reach a top speed of more than 160 km/h thanks to its 35 hp. However, the motorbike crisis of the late 1950s and poor car sales plunged BMW into its deepest crisis since 1919. Even the world championship titles in sidecar racing could not halt the decline in motorbike sales.

The new BMW Motorrad programme presented in 1955 was first-class: The engines basically remained the same, but the new full swing-arm chassis of the R 26 single-cylinder and the R 50, R 60 and R 69 boxer models reformulated the term ‘riding comfort’. Nevertheless, without orders from the authorities, BMW would have had to stop building motorbikes.

The breakthrough in the automobile business came in 1962 with the ‘New Class’, the sophisticated BMW mid-range cars. This brought money to be able to invest in the motorbike programme again. A new motorbike model was developed in 1963. The new engine was borrowed from automobile construction. A new feature – in addition to the kickstarter, which was still present – was the electric starter. New detail ideas such as the folding seat, the removable tool tray and the GRP mudguards were practical innovations that became typical of BMW motorbikes.

The move of BMW Motorrad to Berlin

BMW cars, on the other hand, sold so well that the decision was made in 1967 to relocate motorbike production to Berlin, which was completed in 1969.

The time had come for the 1970 model year. A new generation of BMW motorbikes, the so-called /5 series, was available at dealerships. The sales success of the new machines on the revitalising motorbike market was intended to strengthen the motorbike faction at BMW. It was noticeable that the most powerful machine, the R 75/5, sold best. In 1971, BMW therefore began to consider whether the next top-of-the-range BMW model on two wheels should be able to compete with the Honda CB 750 and exude both sportiness and exclusivity.

The quartet of /6 models presented in September 1973 not only incorporated the latest technical trends of the time, such as five-speed gearboxes and disc brakes on the front wheel, but also documented the influence of professional design. Hans A. Muth had conceived the sporty and elegant design of the R 90 S, with standard cockpit panelling and a sporty-looking seat cover with elaborate gradient paintwork. The designer piece went down well with the public. The great success of the R 90 S – despite its high initial price – proved its advocates right.

The R 90 S had shown that the trend was moving away from the simple universal motorbike. The path to product diversification at BMW was to lead into the 1980s via a skilfully varied modular system. Hans A. Muth styled the fully enclosed R 100 RS as the top model of the new /7 series. It was the world’s first fully enclosed large-scale production motorbike. The diversification of the programme continued in 1978 with the R 45/R 65 and the R 100 RT, the ‘touring bike’.

The break with tradition at BMW Motorrad

At the same time, the decision was made to build the BMW K 100. This motorbike was the most radical break with BMW tradition: a tubular frame, four cylinders, water cooling, fuel injection and DOHC technology were hard to swallow for the old boxer fans. Added to this was a concept that had never been seen before. Four cylinders in line with a longitudinal crankshaft and shaft drive to the rear were already familiar, but no one had ever tilted the block 90 degrees to the left. The unusual prestige motorbike would have to wait another five years.

BMW therefore needed an interesting transitional model. BMW technicians had built ‘Enduros’ from boxers and from this they now developed an all-round motorbike that brought the charm of a Range Rover into the then extremely spartan world of Enduros.

It was mocked that the R 80 G/S (off-road/road) was too heavy and too wide off-road and not ‘sophisticated’ enough on the road. But with astonishing successes, such as a fresh European championship title behind it, the motorbike was presented in 1980. After initial teething problems, the G/S became a trendsetter. Equipped with an unusual single-sided swingarm, the BMW became the archetype of the new ‘touring enduro’ genre. The G/S had breathed new life into the boxer and the antiquated drive was also given new honours in rally sport.

Three years later, the new BMW K 100 shocked with its unconventionality. However, it impressed with its low centre of gravity, good ergonomics, low fuel consumption and long service life. The K 100 was joined by a three-cylinder version in 1985 thanks to the clever modular system. Compared to Japanese sports bikes, the BMW K 75 was frighteningly expensive and comparatively lame. Nevertheless, for a long time it remained the most economical, most suitable for touring and most durable 750cc machine. On the eve of reunification, the aerodynamically clad BMW K 1 based on the K 100 RS was created as a technology carrier. The K 1 was a world first with digital engine electronics, combining ignition and injection in a single unit. It was also the first motorbike with an anti-lock braking system and a regulated three-way catalytic converter.

With the Paralever swingarm, which reduced gimbal reactions, the almost 20-year-old boxer lined up for the final lap. As the R 100 GS, it not only sent its rivals in the touring enduro segment to their knees, but the R 100 R roadster version also became the best-selling motorbike in reunified Germany in 1991. With the nostalgia and ‘Classic’ series, fans were offered cult material until 1996.

The return of the boxer

At the same time, a new boxer entered the ring 30 years ago. In 1993, the time had come: everything was new, only the concept had remained the same. An air-cooled twin-cylinder boxer stretched its cylinders sideways into the wind and a shaft in a Paralever swingarm drove the rear wheel, which was suspended on one side. But there was no longer a frame. A rear frame and a steering head were bolted to the front of the engine housing. Instead of two valves, the combustion chamber breathed in and out via four valves each. The camshafts located next to the cylinder were each driven by a chain from the crankshaft. This unusual configuration made the valve train more resistant to revving than its predecessors, but avoided the (overly) wide cylinder heads that would have been necessary with an OHC solution. With fuel injection, a displacement of 1,100 cm³ and 90 hp, the new boxer was not overbred, but offered better performance, exhaust and noise values than the previous ‘two-valve engines’. At the front, the patented ‘Telelever’ ensured a clean separation of wheel guidance and suspension. A suspension strut sat between the steering head and a wishbone. The handlebars were supported by the engine housing and were connected to a fork that only served to guide the wheel. The advantages over a telescopic fork were the finest response and minimal fork dive when braking. G Cat and ABS were initially available at extra cost, but later became mandatory.

While the touring R 1100 was initially received somewhat cautiously, the R 1100 GS, which followed a few months later, was to become the ‘Swiss army knife’ of big bikes. It rapidly developed into one of the best-selling large-displacement motorbikes and quickly took the top spot in the German registration charts. With the successor models R 1150 GS and R 1200 GS, the great success was extended even further. In addition, BMW Motorrad has continued to diversify its motorbike programme over the last 30 years. From 1993, the F 650 and its successors, which were assembled by Aprilia, took a completely new, globalised approach in terms of concept and production technology. Today, the BMW Motorrad range includes everything from small single-cylinder machines to lavish six-cylinder tourers. But the core of the brand remains the two-cylinder boxer with cardan shaft: a concept that does not seem obsolete even after 100 years …

Text Karl Nachtigall, Photos BMW AG

Author: PS.SPEICHER

PS.SPEICHER is Europe's largest classic car museum. 2,500 historic vehicles at five locations in Einbeck are waiting to be discovered. From the interactive and playfully staged journey through time through mobility to special exhibitions for motorbikes, cars and commercial vehicles. View all posts by PS.SPEICHER →