AJS Stormer Y4 250

AJS produced a 247cc motocross bike, the Stormer Y4, from 1968 to 1974. The Y4, also called the Stormer 250, was an innovative dirt bike because it was the first to use leading axle forks and raised shocks. In addition to these innovative features for the time, the AJS Stormer Y4 had a four-speed transmission and right-side shifter, a 32mm Amal MK1 “932” carburetor, and Flywheel Magneto ignition. The engine had a bore and stroke of 68x68mm, and between 6,000 and 8,000 rpms, it put out a modest 25 horsepower.

When they were introduced to the motocross market, the AJS Stormer Y5 had an orange or yellow gel-coated gas tank, which helped the bike stand out. This 229-pound Y4 also came standard with Dunlop Sports tires, a Reynolds chain, and Girling shocks. The 1968 and 1969 British 250cc Championships were won by Malcom Davis aboard a Stormer Y4.

Japanese-made Yamaha and Suzuki both introduced similar bikes to American riders around this time, however at a much more affordable price. AJS decided to give them a run for their money, though, and within a few short years, they were offering the Y4 at a very competitive price.