1947 Norton 633cc Big 4

1947 Norton 633cc Big 4

Like many manufacturers of the day, Norton relied on outsourced power for their motorcycles for the first few years at the turn of the last century. By 1907, they developed their own side-valve single, which would power their new ‘Big 4’ model. Initially a long-stroke (82x120mm) at 633cc capacity, the engine was revised and became the Model 16 and was considered by many to be an ideal sidecar powerplant. It continued as a stalwart of the Norton range through service in World War II, also in 500 and 600cc iterations, until production ceased in 1954.

The motorcycle offered

The 1947 Norton 633cc Big 4 offered here is a fairly complete project. The bike has matching engine and frame numbers: ‘B’ denotes 1947, ‘7’ is for the Big 4 and the bike’s production number is 8797. The engine has compression, and the magneto has spark. The cycle parts are complete and the missing parts should be fairly readily available to complete the bike.


1947 Norton 633cc Big 4

Engine no. B7 8797
Frame no. B7 8797

Location: Glendale, California