http://www.classicjapcycles.com/articles/the-1976-kawasaki-kd-400The 1976 Kawasaki KD-400
This conversation has been had more than once, and with no proof, couldn't be settled.....until now. Kawasaki had built an open class 450cc enduro machine in the early 1970's, known as the Baja 450. it sported a hand built chassis and various components from both Kawasaki, and the After market world. That bike lived a short life and was never put into production. Then in 1976, Kawasaki built a rumored six of what they called the KD-400. The KD models included versions in 80cc, 100cc, 125cc, and finally in 175cc, all of which were in mass production.
The idea was to build a more modern enduro bike but first, how would it perform, and would it sell? A hand full were built, one of which still survives. As the story goes, it was sent to a dealer in the United States for evaluation, and he kept it until recently, when it resurfaced. It has changed hands twice now and apparently, no spare parts are available...no surprise as prototypes are special.
At the time this bike was being tested, Suzuki was about to release their model PE-400, and Yamaha had already began production on their model IT-400, both of which were light years ahead of the KD-400 with the exception of the KD's disk brakes, and hence why it never made it to production. A few years later Kawasaki did produce the model KDX-420, which was much more in line with its competitors. Pics of the KD-400 are below thanks to John Laurent.