Introduced in 1937, Harley-Davidson’s Model U carried the company’s side-valve Big Twin design into the wartime years. Its 74-cubic- inch, approximately 1,200cc V-twin delivered steady pulling power through a three-speed gearbox, with a hand-operated gear change and foot clutch. A rigid rear frame and springer front fork completed a sturdy, straightforward machine suited to demanding service.
During the Second World War, the US Navy used Model U motorcycles for shore-patrol duties around naval bases and ports. These machines supported policing, messenger work and local transport, with the Big Twin also capable of hauling a sidecar. By 1945, the Model U represented a well-established branch of Harley-Davidson’s military production, serving alongside the smaller and more numerous 45-cubic-inch WLA.
