FOR THE 1954 JUNIOR TT, race development chief Ike Hatch developed a threevalve version of the 348 cc 7R. As well as changes to the cylinder head and cam box, the bore and stroke dimensions were revised to a near-square 75.5 x 78 mm.
The 7R/3A, or “Triple Knocker,” so called because of its three cam lobes, used the frame and running gear developed for the firm’s Porcupine racers. Hatch went on to develop a shaft and bevel drive for the machine’s triple-camshaft top end, but the project was shelved by the firm’s accountants.
| Model: | AJS 7R/3A |
| Capacity: | 350 cc |
| Power output: | 40 bhp (8000 rpm) |
| Weight: | Not known |
| Top speed: | Not known |
| Country of origin: | UK |
BASIC FRONT
The sparse front view of a racing bike from the early Fifties was not hidden behind a fairing. That was soon to change as aerodynamic “dustbin” fairings covered the front wheel of the bike as well as shielding the rider from the wind.
