With the Second World War well under way and with the American entry into the hostilities at the end of 1941, the U.S. Government placed orders with Harley-Davidson for a stout military motorcycle, and the 45 cubic inch sidevalve V-Twin WL model was selected. More than 88,000 examples would be built between 1941-45 with spares for an additional 30,000 bikes produced. The WL would be built as the WLA for the U.S. army, with 20,000 examples designated WLC and sent to the Canadians. Every armored division listed 540 WL bikes in its complement of vehicles.

Testing of the WLA was conducted in Louisiana and it was grueling. The Harley had to ford a stream 16 inches deep, requiring a breather as high as the gas tank, and if the bikes went too fast, water would short out the plugs. As hard as the trials were, the WLA proved immensely durable – if heavy – and served in every theater of the war. It could be dropped in the mud if the rider came under fire, and would restart when lifted upright.

The WLA was fitted with a substantial luggage rack to carry a 40 lb radio, a scabbard for a Thompson machine gun or a rifle on the right front fork, blackout lights front and rear and an engine skid plate. Oddly, the Canadian WLC bikes featured the clutch on the right, brake on the left, right-foot gearshift and the horn above the headlight instead of below it. They also lacked a rear view mirror.

About 1,000 examples of the experimental XA model were also built. It was a shaft-drive curiosity that owed much to the German Zundapp sidecar combination, with a 45 cubic inch side-valve, horizontally opposed engine and shaft drive. The inability of either the WLA or XA sidecars to function in mud prompted the speedy development of the Jeep – whose four-wheel drive was up to the task.

The WL was produced after the war as late as 1951, in civilian colors, and proved virtually indestructible. While a genuine military WLA model commands a higher price, retrofitting later WLs can be difficult since collecting the correct military options can be challenging. Either way, the Harley-Davidson WLA is one of the iconic American military vehicles of the Second World War and remains a common sight at museums and parades. Its appeal is timeless and its historical significance huge, which makes it a very popular choice for collectors.