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 KR Harley-Davidson KR The Harley-Davidson KR or KR750 was a displacement V-twin engine racing motorcycle made by Harley-Davidson from 1953 through 1969 for flat track racing. It was also used in road racing in the KRTT faired version. When the KR was first introduced, it dominated motorcycle racing in the United States. In 1970 it was replaced by the long-lived and US race-winning Harley-Davidson XR-750. American Motorcyclist Association (AMA) Class C racing was created in 1933 in response to low participation in racing and slow motorcycle sales during the decline in consumer disposable income of the Great Depression. The year before,