Introduced at the 1927 Motor Cycle Show, the ES2 sports roadster used the Model 18's overhead-valve engine in the cradle frame of the overhead-camshaft CS1, and from then onwards the 'ES2' designation was always applied to Norton's top-of-the-range, overhead-valve single. The ES2 was built in several versions during a production run lasting until 1963, though the engine dimensions of 79x100mm bore/stroke - first adopted by James Lansdowne Norton in 1911 - remained unchanged to the end. Post-war developments included the adoption of Roadholder telescopic forks (1947), an alloy cylinder head (1955), alternator electrics (1959) and the slimline version of the race-developed Featherbed frame, introduced on the single-cylinder range for 1961. Production of all of Norton's traditional singles ended in 1963, though the 'ES2' model name lived on until 1966, in its latter years referring to AMC's Matchless G80, which was contentiously re-badged as a Norton.
This late, matching-numbers ES2 incorporates all of the aforementioned developments and thus represents the model in its ultimate form. In addition, it has been upgraded with a Lucas racing magneto and an Amal Concentric Mk2 carburettor. '611 NMC' was inherited from his father by the late owner in 2007 and had has been in storage for some considerable time. Careful re-commissioning and the customary safety checks will be required before it returns to the road. Sold strictly as viewed, the machine is offered with an instruction manual and a V5C registration document.