The model range was entirely revamped in 1969 with the introduction of the BMW /5 range, consisting of the 500 cc BMW R 50/5, the 600 cc BMW R 60/5 and the 750 cc BMW R 75/5 models. The engines were a complete redesign, with the crankshaft bearings upgraded from roller bearings to shell-type journal bearings (the type used in modern car engines). The camshaft was now chain-driven camshaft and located underneath the crankshaft instead of at the top of the engine, in order to lower the centre of gravity. An electric starter was available for the first time, although the traditional gearbox-mounted kick starter was also retained. The styling of the first models included chrome-plated side panels and a restyled tank. In 1973, the rear swingarm was lengthened, which improved the handling and allowed a larger battery to be installed.
BMW R75/5 (1969–1973)
The introduction of the "/5" models coincided with production relocating from Munich to a new factory in Spandau, West Berlin. At a site earlier occupied by a Siemens aircraft engine factory.
The BMW /6 range replaced the "/5" models in 1974, with the 500 cc (31 cu in) engine being discontinued and a 900 cc (55 cu in) engine introduced. The "/6" model range consisted of the 600 cc BMW R 60/6, the 750 cc BMW R 75/6, the 900 cc BMW R 90/6 and the sporting 900 cc BMW R 90 S. Other upgrades included a five-speed gearbox, brakes and the electrical system. In 1975, the kick starter was finally eliminated.
BMW R75/6 (1973–1976)
In 1976, the BMW /7 range replaced the "/6" models. The 800 cc BMW R 80/7 model was introduced, and the 900 cc BMW R 90/6 and BMW R 90S models were replaced the 1,000 cc BMW R 100/7, BMW R 100S and BMW R 100RS models. The latter was a full-fairing design which produced 51 kW (68 hp) and had a top speed of 200 km/h (124 mph). Later variants of the 1,000 cc models included the BMW R 100T ("Touring"), the BMW R 100 RT and BMW R 100CS ("Classic Sport").
The 1978 BMW R 45 and BMW R 65 were entry-level 450 cc and 650 cc models that replaced the BMW R 60/7. Later variants of the BMW R 65 included the 1982 BMW R65 LS, the sporting BMW R 65 S and the 1987 dual-sport BMW R 65 GS.
