The WLA is a model of Harley-Davidson motorcycle that was produced to US Army specifications in the years during and around World War II. It was based on an existing civilian model, the WL, and is of the 45 solo type, so called due to its 45 cubic inches (740 cc) engine and single-rider design. The same engine, in a slightly lower state of tune, also powered the three-wheeled Servi-Car (the G family), leading to the solo distinction. Harley-Davidson began producing the WLA in small numbers in 1940, as part of a general military expansion. The later entry of the United States into World War II saw significantly increased production, with over 90,000 being produced during the war (along with spare parts the equivalent of many more). Harley Davidson would also produce a close WLA variant for the Canadian Army called the WLC and would also supply smaller numbers to the UK, South Africa, and other allies, as well as filling orders for different models from the Navy and Marine Corps.