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Norton Big Four Combination 1925 633cc 1 cyl sv

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Norton Big Four Combination 1925 633cc 1 cyl sv

Manufacturer: Norton

Model: Big Four

Year: 1925
Displacement: 633 cc
Cylinder: 1
Engine type: 4-stroke / sv
Bore / Stroke: 82 x 120 mm


Frame number: 16146
Engine number: 13106

Manufacturer: Norton Model: Big Four Year: 1925 Displacement: 633cc Engine type: 4-stroke / sv Cylinders: 1 Bore/Stroke: 82x120mm Frame number: 16146 Engine number: 13106 Norton relied on proprietary engines in its formative years - winning the inaugural Isle of Man TT with a Peugeot-engined machine - before introducing its own design of power unit in 1907. Designed by company founder James Lansdowne Norton himself, the long-stroke sidevalve single displaced 633cc, and the new model it powered became known as the 'Big 4'. Smaller capacity versions followed, and in 1911 the 500 adopted the classic 79x100mm bore and stroke dimensions which would characterise the half-litre (actually 490cc) Norton for the next 50 years. The 490cc engine was revised for 1914 and in 1921 the Model 16, as it had become known, received a new lower frame, becoming the 16H. Norton's trusty sidevalve would be continuously up-dated for the next 30-plus years, the engine arriving at its final incarnation, with dry sump lubrication and magneto repositioned behind the cylinder, in 1931. Many 16Hs saw service with Allied forces in WW2 before this long-running model took its final bow, together with the Big 4, in 1954.

This Big 4 bike is completed with a period sidecar. It’s equipped with a complete acetylene lighting set on both bike and sidecar, Klaxon horn and ML Magneto. The powerful 633cc single produce much of torque and transmit power via the heavy duty Sturmey Archer 4 bolt gearbox to the rear wheel. The stroke have an amazing number of 120mm! This Norton combination is in superb condition and has been restored to high standard.