A Brief History of the Marque
Paul Mühlbach, Kamenz (Saxony)
The German (1) Adria firm's main business was building engines for automobiles and boats. Their motorcycles utilised sidevalve singles of 276cc and 346cc. Another source says the engines were 276cc & 282cc. Early models were single-speed belt drive, later models had three speed gearboxes.
Some engines were supplied by Lutz. (SF)
Notes: 1) SF lists the manufacturer as Swiss, not German.
Source: Henshaw, SF