BSA M20: Top Facts On One Of The Vintage Bikes That Won The War
The BSA M20, a classic general-purpose motorcycle, is one of the contenders of ‘bikes that have won the war.’ The BSA M20 bikes which are still used today can be thought of as direct, living links to the finest hours of World War II.
The BSA M20 was a real workhorse used mainly in the armed service, as well as in delivering the post and other crucial correspondence during war times. This model was created by Val Page, a renowned and radical British motorcycle designer for Ariel and JAP.
Being built for military specifications, the BSA M20 initially started with a hand-change gearbox with a lever on the right, girder forks and a rigid frame. The hand-change suited sidecar usage, but was eventually dropped and replaced in 1939 by a right-foot operated lever in a one-up, three-down arrangement.
Check out this fantastic video by Simon Hadden of a BSA M20 being used and maintained throughout the different seasons in a year.
The BSA M20 (1946) motorcycle being used and maintained through the course of one year.
Credits: Simon Hadden (https://www.youtube.com/watch?v=Xse0tCo7iRA)
This short video with Ian Wright shows the BSA M20 as a dispatch bike. The clip was intended as a tribute to World War II veterans who rode the BSA M20, whether in the armed services or in delivering crucial communication.
Credits: FRL Media (https://www.youtube.com/watch?v=KDr4mTnEXWU)
The Birmingham Small Arms Company (BSA) has built more than 126,000 of the BSA M20 model for the War Office. During World War II, the BSA M20 was one of the workhorses of the English dispatch riders. Today, it has evolved into the popular vintage bike that won the war and is popular as the longest-serving military motorcycle model in the history of British motorcycling.
The BSA M20 is still in use today around the globe, although only a few thousand remain. Check out this video for motorcycle newbies on how to kick start a BSA M20.
Credits: Poppy Raw (https://www.youtube.com/watch?v=UFxzantFZ6s)
BSA M20: Top Facts You Should Know
- In 1936, Val Page reworked the existing BSA designs and the following year, the BSA M20 (500cc) together with another model (M21) were introduced as side-valved, single-cylinder bikes. The BSA M20 remains a favourite choice among vintage bikes because of its powerful engine and sound.
- The war office began ordering the BSA M20 model for military use in 1939, and it remained as the standard service motorcycle until the 1950s, despite some initial misgivings.
- The BSA M20 (formerly known as the W-M20 from October 1939) was famous as a robust and reliable dispatch mount, convoy escort, and all-round workhorse.
- Further detail changes and revisions of the BSA M20 took place during war times, leading to enhancements in both the bike’s ease of servicing and reliability. It has a three-gallon fuel tank for extended riding.
- Majority of the BSA M20 motorcycles manufactured were utilised by the British Army. At the same time, both the Royal Air force and the Royal Navy employed the BSA M20 for dispatch riders. This proved the model’s incredible endurance in some of the most hostile environments during the war.
- The BSA M20 comes with a Smith speedometer, the Jaeger ampere meter, and a headlight in two different forms. One type was used was a blackout headlight (which served its purpose during war times), and the civilian model came with a Lucas beam.
- The suspension of the BSA M20 is a girder-type which is fully adjustable and could be set for use on or off the road. Additionally, it has an air filter box which has been made for the desert. This means that the bike’s air intake is generally cleaner when you’re riding it.
- The BSA M20’s low compression ratio and massive flywheel can pull away from a standstill in almost any gear. Although the side-valves ran hot, worked slowly, and often went thirsty, they were also bullet-proof. It could even run on poor quality fuel.
- The BSA M20 had valanced mudguards, a crinkle hub QD rear wheel, and a tank-top instrument panel. The solo BSA M20 can reach 70 mph, and then steadily cruise at around 50 mph, drinking about a gallon of petrol every 56 miles.
- After the war, the BSA M20 (especially the ones with sidecar-mounting lugs) was a popular ride for people who wanted a different means of transport other than the bus, train or bicycle.
BSA M20 Parts For Sale
If you need a specialist who stocks genuine bike spares and accessories for your BSA M20 bike, or pretty much anything for your old bike, check out Australia’s Classic Bike Spares.
Interesting BSA M20 parts are available, including a range of the following BSA M20 originals:
- Steering lock and keys
- Engine sprocket
- Speedo and Tacho Mounting Rubber
- Mainshaft bearing
- Steel clutch plate
- Fork tube bottom nut
- Knee grip plates (pair)
- BSA m20 carburettor (monobloc 376, 1” bore)
- Fork gaiters (pair)
- Chaincase felt washer
- Sump filter gasket
- Kickstart rubber (open)
- Gearbox sprocket oil seal (BSA plunger)
- Friction clutch plate (BSA 6-spring)
- Friction clutch plate (BSA 6-spring Surflex)
- Clutch inner bearing set (BSA 6-spring)
- Handlebar mounting clamps (pair)
- QD Hub Felt Washer
- Petrol Tank Badges (Piled arms) BSA 1957-62
- Knee grips (pair) BSA M Models
- Front brake cable 35”, BSA 7” hub (Doherty)
- Clutch Spring (BSA 6-spring)
- Steering head dust cover (BSA)
- Oil filter element (BSA M20)
- Choke cable 33”
- Steering head adjuster sleeve
- Steering stem nut with hole
- Mainshaft bearing LS8
- Fork stanchions (pair)
- Gasket set
- Speedo cable 56” (BSA 1954-62)
The BSA M20, together with other war bikes, have made a comeback in recent years. Moreover, these vintage bikes carefully have to be preserved and maintained by the generations today. After all, it is a truth that the preservation of the past can influence the success of the future.
The BSA Owners Club is a great source of information and bikes.