A.J. Stevenson & Co. Ltd., made cars and motorcycles, under the name AJS, between 1909 and 1931. Holding 117 motorcycle world records within the span of a few years, AJS were certainly one of the leading sporting marques. Later in its life, the company was bought by the Matchless, then Associated Motorcycles and then the Norton-Villiers group. And AJS is now one of the few surviving names from this time.
In 1897, Joe Stevens constructed his own internal combustion engine, although his engines entered production only after 1900. He constructed a motorcycle with based on JAP V-twin engines in 1905, at Stevens Screw Company founded by his father, where all the family members were employed.
In 1909, A J Stevens & Co was founded to manufacture motorcycles. In 1911, the earliest model was launched, a dual-speed 292 cc side valve, and AJS entered in the Isle of Man TT races, wherein A J Stevens ranked fifteenth in the Junior TT.
The company, Albert John Stevens was actually a family company by 1926, with Harry Stevens as its Engineer, Joe Stevens junior as its Production Engineer, Albert John Stevens taking charge of designing, and George Stevens as the Chief Salesman.
AJS had always been very closely associated with the Isle of Man TT. By 1914, the company had developed a 350cc motorcycle, with chain final drive and a four-speed gearbox. It took part in the Isle of Man TT race of 1914, and won the first, second, third as well as fourth places in the Junior TT. In 1920, chain primary drive and internal expanding brakes were introduced. Once again AJS won the Junior in the years 1920 (ridden by Cyril Williams), 1921 (AJS bagged the first four places of Isle of Man TT, with Howard R Davies winning the Senior on 350cc AJS) and 1922 (the Junior was won by Manxman Tom Sheard, and G Grinton came second). In 1929, Wal Handley got the second place in Junior TT, while Jimmy Guthrie won Lightweight TT in 1930, on an AJS.
In 1916, non-military motorcycle production was prohibited by Ministry of Munitions. Russia gave an order for military vehicles to the Ministry in 1917, and a part of it was given as contract to AJS, keeping it busy till the restrictions of the Ministry were lifted in early 1919.
AJS launched two chain-driven racing models with overhead camshaft namely, the 498cc K10 and the 349cc K7, in 1928. Again in 1929 the 498cc M10 and 349cc M7 were launched. A 496cc transverse V-twin with shaft primary drive was launched in 1931.
However in late 1931, the company was in financial trouble, as it had taken loans to build its business in making cars, buses and coaches. Its motorcycle assets were purchased by Matchless, run by the Collier brothers, London. In 1938, AJS was taken over by Associated Motorcycles, sharing models under different badges. The racing heritage of AJS was used by Colliers on innovative racing machinery, thus keeping the AJS name alive.
Eventually, in 1966, Associated Motorcycles, along with the AJS name were taken over by Norton-Villiers. The AJS name was used on an off-road machine, the AJS Stormer, based on a two-stroke engine. Today, AJS has a range of four-stroke bikes of 125cc in both off-road and in-road versions, as well as cruisers with 250cc, 125cc and 50cc parallel twin engines.