1929 Harley-Davidson Model "D" Sidecar
Engine: V-Twin 450
Cubic capacity: 746 cc
Power: 18.5 hp 4000 rpm
Max Speed: 100 km h
Weight: 380 kg
Bore x stroke: 70 x 97 mm
Compression: 5.0:1
Valves: 2
Power supply system: Carburetor
Dosage: Pedal
In the late summer of 1929, Harley-Davidson introduced its 45 cubic inches (737 cc) 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 2.745 in (69.7 mm) bore and 3.8125 in (96.8 mm) stroke would continue in most versions of the 750 engine; exceptions include the XA and the XR-750.