“1909 Harley-Davidson V-twin motor." Courtesy of the Harley-Davidson Archives.

When Edward Pennington unveiled the first prototype for what he deemed the “motorcycle” in 1895, inspiration struck the minds of two Milwaukee natives, William Harley and Arthur Davidson. Joined by Arthur’s brother, Walter, the three began tinkering with two-wheelers and eventually designed their own.

Their initial efforts proved to be less than satisfactory, however, as the six prototypes they churned out were no match for the city’s dirt terrain. While the company found some local success, they needed a new approach to kickstart their brand. This prompted William to enroll in the University of Wisconsin-Madison to study Mechanical Engineering. After returning from his studies, Harley applied his knowledge to redesigning their motorcycle. The result was what would become their signature accomplishment— the V-twin engine, which was introduced in 1907.[1] The new engine rapidly found nationwide success and would eventually serve as their claim to fame.

“Close-up of a 1909 Harley-Davidson motorcycle with the newly designed V-twin motor.” Courtesy of the Harley-Davidson Archives.

Characterized by two twin cylinders splayed at a 45-degree angle, this revolutionary design allowed for unparalleled power and performance. With A 49.5 cubic inch displacement, or internal size, the metal contraption produced seven horsepower in output. The engine was widely referred to as an “F-head,” as the arrangement of the internal intake valve positioned the cylinder head and exhaust to resemble the shape of the letter.

In 1908, this new technology was put to the test at the Long Island Endurance Race. Drawing in competition from all corners of the nation, it served as a way for upcoming brands such as Wagner, Thor, Excelsior, and Simplex to display their technological prowess.

Using their new engine, Harley not only came in first place but achieved a perfect score based on endurance and performance, ushering in the company’s reign of domination from the early to mid 20th century in Wisconsin and beyond.

Written by James Apter, March 2022

Two different angles of the complete 1909 H-D bike. Courtesy of the Harley-Davidson Archives.


[1] Margie Siegal, “Mechanical Beginnings,” in Harley-Davidson: A History of the World’s Most Famous Motorcycle (Oxford: Shire Publications, 2014), p. 18.

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