AJS has built the 7R, a classic motorcycle, across 1 variant since 1952. Under the tank sits a single cylinder, 4-stroke, OHC Triple-Camshaft. It makes 40 hp at peak.
About the AJS 7R
The AJS 7R was introduced in 1948 and remained a competitive force in the 350cc class for nearly two decades. Technically, the 7R was a masterpiece of simplicity and efficiency, featuring a chain-driven single overhead camshaft (SOHC) engine. Designed by Phil Walker, the engine was noted for its reliability and "tuneability," making it the weapon of choice for privateer racers at the Isle of Man TT and across European Grand Prix circuits.
The 7R featured a lightweight magnesium crankcase and a distinct "conical" hub braking system. Over its production life, the technical specs evolved, with the engine eventually producing nearly 40 bhp in its final "triple-cam" factory iterations. This database provides the technical dimensions, bore and stroke (initially 74 x 81 mm), and the specialized racing weights of the 7R. For historians and collectors, the 7R represents the golden era of British racing singles, where engineering elegance met track-dominating performance.
AJS 7R by Year
Spec Evolution
How key specs changed across production years.
No numeric spec data available for this model.