The story
The Killinger and Freund Motorrad (motorcycle) was test-driven after the engine was tested on a test stand. Its total weight was 135 kg (297 lb).
This design was intended for civilian production but the start of World War II cancelled those plans. One motorcycle was discovered by the US Army in the spring of 1945 at a German military installation but it is not known if this was the original prototype or another Killinger und Freund Motorrad. It was sold as scrap in the United States after a short period of display. In 2010, Motohistory.net had a short article detailing the bike's current condition.
From Wikipedia’s article on Killinger and Freund Motorcycle, shared under CC BY-SA 4.0.3