The Konig 500 was a competitive racing machine in the 1960s. As mentioned in Konig: From Watercraft to Motorcraft, the origin of the Konig 500 was a 494cc two stroke flat four engine that powered a racing outboard boat. Packaging problems to overcome, particularly when the boxer engine was placed in the chassis lengthwise like an early Douglas, rather than across the chassis like the BMW boxer. Clever packaging, innovative valve configurations, and enhanced cooling, helped to make the bike a strong performer. But this is only partially about the Konig.
As the 1970s began, Konig translated its' success into race-ready lists, but they also attracted a surprising potential partner. BMW expressed an interest in building production road machines based on placing the Konig motor in a BMW chassis. Discussions progressed, and two prototypes were built in 1972. One was a 350cc sport model, while the other was a 500cc tourer. The motor was rotated 90 degrees into the familiar BMW layout, and it was placed into a modified R90 chassis where it was mated to a BMW gearbox. Unfortunately, it never progressed beyond the prototype stage, as BMW ultimately rejected the idea of a two-stroke.
Both prototypes still exist. The 350cc in the Konig museum, and the 500cc has been privately restored.