The BMW R90S was a family of motorcycles that debuted for the 1974 model year. The R90S was a sport variant of the /6 Series that was powered by a 898cc horizontally opposed twin engine that had an output of 67hp. This engine drove the rear wheel through a 5 speed transmission that sent its power to the wheel via shaft drive. A popular model, a total of 17,455 examples of the BMW R90S were built before the end of production in 1976.