1955 Ariel 998cc Square Four MkII
Registration no. RGF 659 (see text)
Frame no. PS387
Engine no. GL372

Designed by Edward Turner, creator of the legendary Triumph Speed Twin, the first Ariel Square Four was shown at the Olympia Motorcycle Show in 1930. Conceived as an overhead-camshaft 500, the model grew to 601cc before a total redesign saw it emerge as the Model 4G, with 995cc overhead-valve engine, in 1937. Anstey-link plunger rear suspension became an option in 1939, but would not be offered again until 1946, when a telescopic front fork replaced the previous girder type. An exercise in weight shedding saw the cast-iron cylinder head and barrel replaced by alloy components for 1949, the revised model, now capable of 90mph-plus, being known as the Mark I. Introduced in 1953, the 'four pipe' MkII with re-designed cylinder head elevated the Square Four into the league of genuine 100mph motorcycles. Square Four production, along with that of all other Ariel four-strokes, ceased in 1959. To date, the innovative Ariel Square Four remains unique in motorcycling history; a true 'gentleman's motorcycle, this refined yet charismatic machine retains an enthusiastic and loyal following, and is highly prized by discerning enthusiasts. An older restoration, this Square Four MkII is described as in generally good condition, its engine said to be in very good running order. Previously registered 'RGF 659' in the UK, the machine formed part of an Italian private collection from 1992 to 2012 and still carries its last tax disc. Offered with bill of sale. No reserve.