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 Model 7D Harley-Davidson Model 7D The Harley-Davidson Model 7D of 1911 was the first successful v-twin from Harley-Davidson, inaugurating a motorcycle engine configuration that has continued unbroken from the Milwaukee motor company ever since. In 1909, Harley had made a few examples (27 units) of another v-twin, but the design was flawed and they did not try again until two years later. In 1911, 5,625 Model 7Ds were manufactured. The Model 7D's motor was the F-head IOE engine, in use until 1929. It sold for US $300, which with inflation would be $ in today's currency. Ignition was via a magneto, and