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 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.