Comparing the BSA A7 and Norton Model 7

Head-to-head on a 1949 BSA A7 Twin and a 1952 Norton Model 7.

Norton Model 7
Presumably to avoid infringing BSA patents, Norton chief designer Bert Hopwood positioned the single camshaft at the front of the engine instead of the rear, driven by chain from a half-time gear.
Photo By Robert Smith