The BSA D1 was more commonly known as the BSA Bantam and was based on the German DKW RT125 like many other bikes including the Harley-Davidson Hummer, and the Yamaha YA-1.
The BSA D1 was more commonly known as the BSA Bantam and was based on the German DKW RT125 like many other bikes including the Harley-Davidson Hummer, and the Yamaha YA-1.