Harley-Davidson models. In the late summer of 1929, Harley-Davidson introduced its 45 cubic inches (737 cm³) flathead V-Twin to compete with the Indian 101 Scout and the Excelsior Super X. This was the "D" model, produced from 1929 to 1931. Riders of Indian motorcycles derisively referred to this model as the "three cylinder Harley" because the generator was upright and parallel to the front cylinder. The Great Depression began a few months after the introduction of their 45 cubic inch (737 cm³) model. Harley-Davidson's sales fell from 21,000 in 1929 to 3,703 in 1933. Despite this, Harley-Davidson unveiled a new lineup
Harley-Davidson Museum housed on the museum's grounds. The archives supplied more than 85% of the items on display in the museum. Since 1915, the company's founders decided to pull one bike from the production line to be preserved in an archive. Harley-Davidson Museum The Harley-Davidson Museum is a North American museum near downtown, Milwaukee, Wisconsin celebrating the more than 100-year history of Harley-Davidson motorcycles. The three building complex on along the Menomonee River bank contains more than 450 Harley-Davidson motorcycles and hundreds of thousands of artifacts from the Harley-Davidson Motor Company's 110-year history. The museum attracts an estimated 300,000 visitors annually. The