BIG FOUR The Big 4 is world. renowned for reliability. It is built throughout of the finest materials available, and its universal success is proof of the soundness of design. The machine is ideally suited to sidecar work. The side valve engine has a capacity of 596 c.c. and a bore and stroke of 82 mm x 113 mm.

Model 16H The Model 16H machine is to the same specification as the Big 4, with the exception that the side valve engine has a capacity of 490 c.c. Bore and stroke 79 mm x 100 mm.
Catalogue

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Norton Big Four