In 1940 the British War Office requisitioned every available Matchless motorcycle to replace those lost at Dunkirk.
 Developed from the pre-war G3, the 'L' in the G3/L stood for "lightweight" in response to the War Office requirement for a motorcycle more suited to off-road use, as the designers managed to reduce the dry weight of the prototype by 56 pounds (25 kg) (although the later models were not so lightweight due to the additional army equipment that needed to be added).
The real innovation of the G3/L was the "Teledraulic" forks, which were the first telescopic design with oil damping – an idea that was to become the standard for almost all future motorcycles.

After exhaustive military testing the G3/L lost the War Office competition for a single standard 350 cc machine to Triumph's 350 cc side-valve vertical twin, the 3TW, which had a top speed of over 70 mph and weighed 240 pounds (110 kg).
Triumph's Priory Street works in Coventry were completely destroyed by German bombers in November 1940 All Triumph's technical records, drawings and designs were lost and Matchless won the contract.
Triumph instead produced 350 cc sidevalves for the military during the war.

Production of the G3/L began in late 1941, and a series of modifications and improvements were introduced as it entered military service.
From 1942 the entire output of the Matchless factory was dedicated to the G3/L.
In 1940 the British War Office requisitioned every available Matchless motorcycle to replace those lost at Dunkirk.  Developed from the pre-war G3, the 'L' in the G3/L stood for "lightweight" in response to the War Office requirement for a motorcycle more suited to off-road use, as the designers managed to reduce the dry weight of the prototype by 56 pounds (25 kg) (although the later models were not so lightweight due to the additional army equipment that needed to be added). The real innovation of the G3/L was the "Teledraulic" forks, which were the first telescopic design with oil damping – an idea that was to become the standard for almost all future motorcycles.
After exhaustive military testing the G3/L lost the War Office competition for a single standard 350 cc machine to Triumph's 350 cc side-valve vertical twin, the 3TW, which had a top speed of over 70 mph and weighed 240 pounds (110 kg). Triumph's Priory Street works in Coventry were completely destroyed by German bombers in November 1940 All Triumph's technical records, drawings and designs were lost and Matchless won the contract. Triumph instead produced 350 cc sidevalves for the military during the war.
Production of the G3/L began in late 1941, and a series of modifications and improvements were introduced as it entered military service. From 1942 the entire output of the Matchless factory was dedicated to the G3/L.
Matchless G3/L