For those with fond memories of the Norton rotaries, it all started back in 1957 when Felix Wankel, with help from engineer friend, Ernst Höppner, developed the first working prototype of the DKM engine.
It turns out this design has some tricky probems with cooling and never made it in to production, but without it the KKM version may never have found its way into the MZ 250 ES, the first production bike with a Wankel engine.
