BMW
After the end of World War I in 1918, BMW was forced to cease aircraft engine production by the terms of the Versailles Armistice Treaty. To remain in business, BMW produced farm equipment, household items and railway brakes. In 1922, former major shareholder Camillo Castiglioni purchased the rights to the name BMW, which led to the company descended from Rapp Motorenwerke being renamed Süddeutsche Bremse AG (known today as Knorr-Bremse). Castiglioni was also an investor in another aircraft company, called "Bayerische Flugzeugwerke", which he renamed BMW.The disused factory of Bayerische Flugzeugwerke was re-opened to produce engines for buses, trucks, farm equipment and pumps, under the brand name BMW. BMW's corporate history considers the founding date of Bayerische Flugzeugwerke (7 March 1916) to be the birth of the company.
History of BMW motorcycles
In 1921, BMW began manufacture of its M2B15 flat-twin engine. Designed by Max Friz for use as a portable industrial engine, the M2B15 was largely used by motorcycle manufacturers, notably Victoria of Nuremberg, and Bayerische Flugzeugwerke in their Helios motorcycle. Friz was also working on car engines.