In 1951 AJS development engineer Ike Hatch developed a 75.5 mm bore x 78 mm stroke, three valve head version of the 7R making . It was called the AJS 7R3, and was Ike's response to the Italian multi-cylinder racers. They did well enough in their first year, not as well the second.
In 1951, AJS engineer Ike Hatch developed a 75.5 mm bore x 78 mm stroke, three valve head version of the 7R, which was named the AJS 7R3. This model responded to Italian multi-cylinder racers and performed well in its first year but not as effectively in its second.