Norton first produced an overhead camshaft engine in 1927, designed by Walter Moore and designated the ‘CS1’ (cam shaft one) it enjoyed immediate success with Alec Bennett winning the Senior Isle of Man TT that year. When Moore left Norton to join NSU in 1929, Joe Craig who was the leading light at Bracebridge Street’s race and experimental department appointed his senior draftsmen, Arthur Carroll to assist him in the design of a new OHC engine. A hybrid engine first appeared at the Olympia Show on the last day of November 1929, using a Moore top end on the new crankcase and timing side assembly. The 1930 Norton model range introduced the two new OHC engines with the 500 at 79 x 100mm bore and stroke and a 350 Junior version at 71 x 88mm. They were designated the CS1 and CJ and they retained the left hand exhaust pipe. Using the old ‘three stay’ frame and the three speed Sturmey Archer gearbox the new models were yet to be fully ‘tweaked’ and their victories that season were few and far between.

By 1931 Norton had ironed out the problems of the previous year and the ‘Cammy’ Nortons swept the board with Tim Hunt taking the first ever ‘double’ at the TT races with a first in both the Senior and Junior races. With riders of the calibre of Hunt, Stanley Woods, Jimmie Simpson, Jimmie Guthrie, the Norton race machines won practically every TT and continental race during the early thirties. When the likes of ‘Crasher’ White, Freddie Frith and Harold Daniells joined the team, Norton continued to dominate the world of motorcycle racing through out the thirties. In 1932 the 500cc International, as it was now called, was given the Model number ‘30’ and the 350 junior was designated the Model 40. In keeping with Nortons dictum of “we only race standard products”, the machines available to the public were very similar to the works machines and many ‘privateers’ enjoyed racing their ‘Inters’ at numerous race meetings all over the world. In late 1936 the Inter was available with a ‘Spring’ frame, which was produced by fitting plunger spring units to the rear of the frame. The machine could be ordered to racing specification and was built in the Experimental Department. For an extra £5 you could have an all alloy top end, an extra ten shillings (50p) would give you a large wrap round oil tank and another £5 ‘special tuning’. Close ratio gearbox without kick starter, racing 3 spring clutch and various other tuning parts were not charged for.

One of the best pre-war Internationals to come on the market in recent times, this example is offered from a collection of fine motorcycles from a deceased enthusiast, this particular machine, produced to ‘Manx’ specification, leaving the factory on 24th October 1937 with magnesium crankcases, megaphone exhaust and rev counter. The frame, engine, gearbox and girder fork numbers all match those documented in the Norton factory records and this indicates that this is a genuine motorcycle that has retained all its original parts. With the spring frame and Manx hubs it was as close to a works type racer the privateer could buy. The engine was rebuilt by Bernard Fowler in 1980 and the machine has been left standing since. The pictures show the cambox oil feed pipe and primary guard missing, but these and other spares should be available by the time of the sale. After careful re-commissioning the noise and the smell of Castrol ‘R’ will provide the new owner with the same thrill and excitement that those heroes from the thirties enjoyed.. A rare opportunity to acquire one of the finest sporting motorcycles from the thirties, close to original specification with all the available racing parts of the period.