What name is given to Harley-Davidson’s first completed motorcycle from 1903?

Harley-Davidson’s first completed motorcycle from 1903 is known as Serial Number One.

The machine was built by William S. Harley and the Davidson brothers in Milwaukee during the company’s earliest development. It was a modest single-cylinder motorcycle, reflecting the experimental character of Harley-Davidson before the firm became a large-scale manufacturer.

“Serial Number One” refers to the motorcycle’s place in the company’s production history rather than being a consumer model name like Softail or Sportster. The surviving machine is an important symbol of Harley-Davidson’s origins.

Early Harley-Davidson history is sometimes confused with the date of incorporation or with the company’s first V-twin. The first V-twin appeared later, while Serial Number One represents the earliest completed Harley-Davidson motorcycle.