c1950 Norton ES2 Motorcycle

Description

Derived from the overhead-valve Model 18, Norton’s long-running ES2 first appeared at the 1927 Olympia Show and utilised the same overhead-valve 500cc engine, albeit with the magneto relocated behind the cylinder with drive coming off the primary chain.  With a bore and stroke of 79mm by 100mm, the ES2 became Norton’s most expensive overhead-valve in the model line-up.  The ES2’s frame was an entirely new cradle design developed for the ohc CS1 and the model underwent almost constant improvement, adopting a saddle tank by 1929, the magneto drive changed to come off the inlet camshaft in 1931 and a second side drive main bearing was adopted in 1934.  By 1938 the ES2’s valve gear was fully enclosed and plunger rear suspension became available the following year.  Production of all overhead-valve engines was suspended during the war years but a heavily revamped ES2 re-appeared post-war, adopting ‘Roadholder’ telescopic forks and revised engine internals by 1948.  Changes continued throughout the 1950s before the ES2 was finally dropped from Norton’s line-up in 1963, although the name itself lived on with a re-badged version of the Matchless G80.