It was based on an existing civilian model, the WL, and is of the 45 solo type, so called due to its 45-cubic-inch (740 cm3) engine displacement and single-rider design.

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.

Unusually, all the WLAs produced after Pearl Harbor, regardless of the actual year, would be given serial numbers indicating 1942 production.

The precise serial number, as well as casting marks, can be used to date a specific motor accurately, and some other parts bear year and month stamps.

Many a young soldier would come home hoping to get a Harley-Davidson like he saw or rode in the service, leading to the post-war popularity of both the motorcycle and the company in general.

With little access to parts and no chopper culture, and no export path to the West, many of those WLAs were preserved during the Cold War.

Allied motorcycles were almost never used as combat vehicles or for troop mobility, and so were rarely equipped with sidecars as was common on the German side.

Harley-Davidson provided motorcycles to the Army during World War I and for earlier excursions against Mexican revolutionaries such as Pancho Villa.

That meant shaft drive, a boxer engine, and several other features that made the BMWs exceptionally reliable and low-maintenance machines.

Due to its new features and low production, the XA was expensive, and by that time it was clear that the Jeep was the Army's general purpose vehicle of choice; the less advanced but cheaper WLA was considered sufficient for its limited roles.

The MT350E was a redesign of the 500 cc Armstrong MT500, which reduced weight, added an electric start, and upgraded pollution standards.