• Works entry at the 1921 Isle of Man TT
• Ridden in 1921 by J W Shaw
• Formerly part of the Autokraft Collection
• Restored in 2012
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. 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 that would characterise the half-litre (actually 490cc) Norton for the next 50 years.
Norton's new sidevalve was among the fastest in its class, being the first machine under 500cc to be officially timed at over 70mph, which was some going for 1911. The following year Norton-mounted Jack Emerson easily won the 150-mile Brooklands TT against a field of more experienced competitors (setting three long-distance records in the process) having ridden his machine down from Hull! Small wonder that the slogan 'Unapproachable' began to be applied to the Norton singles at around this time. Tuner/rider D R O'Donovan's work at the Weybridge track resulted in a flood of new speed records, including 81.05mph for the flying kilometre in April 1914, the first occasion 80mph had been exceeded by a 500cc machine. O'Donovan's successes led to the introduction of tuned 'Brooklands' models, and these highly developed sports versions continued into the 1920s.
The 490cc engine was revised for 1914 and the following year gained a new frame with lowered riding position together with the option of a Sturmey Archer three-speed gearbox. When fitted with chain drive, the 490cc sidevalve single became the 'Model 16' in Norton's numbering system, and then changed to '16H' in 1921 when a new lower frame was introduced. Norton's trusty 16H sidevalve would be continuously up-dated for the next 30-plus years before taking its final bow - along with the Big 4 - in 1954.
When motorcycle racing resumed after WWI, the first post-war Isle of Man TT being held in 1920, it became obvious that the sidevalve's days as a competitive racer were numbered. The best Norton could manage in the 1921 Senior TT was 6th place, prompting James Lansdowne Norton to come up with a new overhead-valve design - the Model 18, which first appeared in 1922. One of Norton's works team in 1921 had been J W Shaw, who had retired from the race following a fall from the machine offered here: 'OH 7083'. Shaw had placed 7th for Norton in the previous year's Senior race, and in pre-war days had won the Irish 50-miles championship for Norton. His last outing at the TT was in 1929.
The current owner purchased 'OH 7083' from Brooks' sale of the Autokraft Collection at the RAF Museum, Hendon in March 1999 (Lot 17). The only known previous owner is Reginald Briggs, who bought the Norton from Victor Horsman's shop in Liverpool (see letter on file). Restored in 2012, the machine remains in commensurately good condition and was ridden on the last two Banbury Runs. One of the last of the factory's sidevalve racers, this rare ex-works Norton is offered with copies of period photographs, a V5C Registration Certificate, and the aforementioned letter.