Beissbarth Motorrad GmbH operated in Munich from 1902 to c.1932. In the years 1902 to 1905 they offered FN motorcycles under their own brand, including the "Beissbarth 4 Cylinder Motor-Rad".
In 1922 and 1923 they offered a motorcycle powered by a 270cc two-stroke engine which had a two-speed gearbox and kickstarter. Final drive was by belt, and it had block brakes on the rear wheel.
The firm offered D-Rad motorcyles from then until about 1932.
Source: Motopedia