When the new generation of motorcycles was presented in 1983 with the longitudinal four-cylinder inline engine, BMW was taking a great stride forward. The entire powertrain with engine, gearbox bolted directly to the engine and the proven single swing arm with integrated drive shaft formed a single unit designated as the "Compact Drive System" by BMW. The unfaired BMW K 100 was the basic model for the new series and was capable of being upgraded with BMW accessories entirely to customers' specifications. The dynamic ride qualities transformed the K models into a model of success crucial for the future of BMW as a motorcycle manufacturer.