How Much is a 1945 Harley-Davidson 45 Flathead Worth at Auction?

The Harley-Davidson 45 Flathead, first produced in 1937, is a landmark 45 ci side-valve V-twin whose simple, rugged engineering appeals to classic car and motorcycle enthusiasts. Known for its flathead design, strong low-end torque and period styling—famously adapted in the wartime WLA—the 45 Flathead embodies vintage character and mechanical accessibility. Its timeless lines, historic service with police and military units, and ease of restoration make the 1937-era 45 Flathead a prized vintage collectible for classic car and motorcycle collectors.