Classic Motorcycle Build

Harley WLA History

Article by Mark Trotta

During World-War-Two, nearly all Harley-Davidson motorcycle production was for military use. Several different models were produced, but the vast majority was the WLA Flathead 45, which saw use in every theater of military operation.

What Harley was used in WW2

Harley Military Bike Development

As war in Europe escalated, the United States saw their odds of being pulled into a second World War increasing. Starting in 1939, the U.S. government began allocating money to build up all phases of their military.


The military began testing motorcycles from several different manufacturers, most notably Harley-Davidson and Indian. Among the requirements were that the motorcycle be capable of 65 mph and not overheat at low speeds.

Military vs Civilian Models

Early prototype models were essentially the same as civilian Harley 45 models, with front forks lengthened slightly to increase ground clearance. Add-ons included crash bars, skid plates, cargo rack and saddlebags.

What Harley was used in WW2
2024 WWII Weekend, Mid-Atlantic Air Museum, Reading, Pennsylvania

On military models, the sides of fenders were trimmed back to prevent mud-clogging on unpaved roads. Headlights and taillights were changed from the civilian model to meet military standards.

Some were fitted with front and rear blackout lights to reduce night-time visibility.

WLA Designation

The letters WLA stand for; "W" indicating 45ci flathead, "L" for high compression, and "A" for Army use.

Compression Ratio

Here in the 21st century, it's hard to believe that 6.0:1 was once considered a high compression motor, but the reader must remember that modern high-octane fuel and high compression engines came after (and were actually a by-product) of WW2.

The U.S. Army specified a slightly lower compression ratio ( 5.0:1) than civilian WL's, allowing them to run on lower quality fuel. Although this decreased power output, it made for easier starting (all bikes were kick-start only). Oil-bath air filters were fitted to reduce dust from dirt roads. All WLA engines were fitted with aluminum cylinder heads.


Harley WLA Engine Specs

Harley WW2 motorcycle


40WLA and 41WLA

After passing requirements and testing, the U.S. Army initially ordered about 400 Harley WLA models. These early examples have a VIN starting with "40WLA". The following year brought the 41WLA.


Within the first few months of America entering the war, the 41WLA evolved into the 42WLA. These would be manufactured for the next four years, up until August 1945. The 42WLA models encompass the vast majority of WLA bikes produced.


All WLA motors produced in 1942, 1943, 1944, and 1945 have a VIN starting with "42", regardless of what year they were built. This was unique in the Motor Company's history, and presumably done to simplify paperwork.

WLA Accessories

Accessories included a luggage rack, ammo box, and leather rifle scabbard. WLA models were also equipped with D-shaped foot-boards.


Motorcycle Ownership and Gun Ownership: Riding With Guns | Primary Weapons Systems


From the factory, WLA motorcycles were fitted with Firestone Sportsman 4.00-18 tires. With few exceptions, all WW2 bikes were painted flat olive drab.

Harley Davidson during World War Two
Picture Courtesy Harley-Davidson


Harley WLC

Harley-Davidson produced a Canadian version of the WLA called the WLC (the 'C' standing for Canada). Differences from the American model included a foot shift/hand clutch, and other modifications requested by the Canadian Army. About 18,000 WLC's were produced for WW2, with some of these going to the United Kingdom and Australia.


Lend Lease

Along with trucks, tanks, airplanes, and ships, motorcycles were supplied to ailing countries through Lend Lease Agreements. Nearly 60 percent of WLA production (over 34,000) were exported under Lend-Lease and other military assistance programs.


Harley WLA in Action

Being big and bulky, the WLA did not have the maneuverability of Britain's smaller motorcycles, nor the off-road capability of German motorcycles, but it's rugged simplicity proved just right for messenger service.

Although WW2 Army Jeeps proved to be more versatile, quite often motorcycle dispatch riders were the fastest way to send orders too secret for wireless transmission.

Harley WLA motorcycle during World War Two
Picture Courtesy U.S. Army

In every theater of operation they were sent to, Harley WLA's reliably transported fully-equipped soldiers with gear and supplies. They were also utilized for escort work, convoys, courier duties, and some scouting. Both during and after the war, they appeared in parades and military police functions.


Excellence Award

The Army-Navy 'Excellence in Production Award' was created in 1942 to recognize industries for outstanding contributions to the war effort. Only industries that participated in wartime production were eligible to receive this high honor.

Harley WLA excellence award

Of the more than 85,000 companies directly involved in the U.S. military's war effort, the award was granted to just five percent of them. The Harley-Davidson WLA received this honor twice; first in 1943 and again in 1945.

Harley WLA military bike history
Picture Courtesy Harley-Davidson

WLA Production Numbers

In all, Harley-Davidson produced about 70,000 WLA and WLC military motorcycles during the war years 1941-1945. The largest portion of these (about 27,000) went to the Soviet Union under the Lend Lease program. Spare parts for an additional 30,000 bikes were also produced.

Harley 45 WLA identification
Picture Courtesy National Motorcycle Museum

WLA Motorcycles After WW2 (Europe)

After the war ended, the U.S. military saw no need to transport used motorcycles back to the states. So, along with trucks, tanks, trailers, and other discarded military equipment, many ended up in scrap heaps. One can only guess how many were destroyed, but quite a few survived and adopted by local townspeople.

WLA Motorcycles After WW2 (United States)

At the end of WW2, the U.S. Army sold many unshipped WLA's domestically as military surplus, often at very cheap prices.

Korean War Harley WLA

WLA production started up again in 1949 and ran through 1952; these bikes were shipped to the Korean peninsula. Some historians note that the WLC was also carried over.

After the Korean War was over, the U.S. Military sold off many WLA's as government surplus, along with spare parts. Many of these surplus bikes were chopped and customized, becoming the very first "choppers" and "bobbers". Because of this, original examples have become extremely rare, and are quite valuable in today's collector market.


Harley 45 Serial Numbers

Stamped in the left engine case, civilian Harley 45 serial (VIN) numbers start with the last two digits of the year, followed by the letter designation, then a four-digit assembly sequence code.

Example: 42WLxxxx

Some Harley WLA motors had an additional number in the VIN.

Example: 42WLAxxxxx

Canadian models are stamped "43WLCxxxx"

Although identical in appearance to WW2 Harleys, Korean War WLA's will have a VIN starting with a 49, 50, 51, or 52. By comparison, WW2 models have VIN's that start with a 40, 41, or 42.


Military Breather Tube

Note the tall breather tube coming out of the front right side of the engine.

WW2 Harley 45 WLA flathead engine unrestored

This was to keep water out of th motor when fording shallow rivers, and standard issue on all Military 45 flatheads.


Related Articles:

Harley 45 Engine Teardown and Inspection
Harley 45 Engine Assembly
Harley 45 Timer And Ignition
Harley 45 Drivetrain
Harley 45 Frame Choices
Harley Bar and Shield logo was first seen in 1910 and trademarked one year later

Read: Harley-Davidson Motor Company History