Harley-Davidson motor cycle and sidecar, 1925. Harley-Davidson started producing motorcycles in 1903 and by 1914 they had realised the key to success in an American car-centric market was a heavy, powerful design capable of travelling long distances with a side car. This example of a 1925 Harley-Davidson motorcycle is a perfect example of this. It has a 989 cc V-twin engine and wide section tyres enabling it to cover long distances reliably in relative comfort, as well as pull along a side-car. These features were worlds away from priorities of European motorcycle manufacturers which held road holding and economy as standard.