Serial Number One – Atmospheric-Valve Single – ca. 1903

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Serial Number One - Atmospheric-Valve Single - ca. 1903
The vehicle known as Serial Number One is a bit of a mystery. Its engine is very early, but doesn't match what we know about the first engines produced by Harley-Davidson. The frame, which dates to 1905, is not original to this motorcycle. These oddities have triggered much debate. During the 1990s, restorers discovered a number "1" stamped inside various components, inspiring the bike's nickname. Because of the questions surrounding it, Serial Number one has become a legend in Harley culture. Only one things is for sure: this is the oldest Harley-Davidson in the world.

The vehicle known as Serial Number One is a bit of a mystery. Its engine is very early, but doesn’t match what we know about the first engines produced by Harley-Davidson. The frame, which dates to 1905, is not original to this motorcycle. These oddities have triggered much debate.
During the 1990s, restorers discovered a number “1” stamped inside various components, inspiring the bike’s nickname. Because of the questions surrounding it, Serial Number one has become a legend in Harley culture. Only one things is for sure: this is the oldest Harley-Davidson in the world.