1953 Ariel 998cc Square Four Mark II
Registration no. JAV 832
Frame no. ES875
Engine no. XJ667

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 redesigned 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.

This apparently well restored Square Four Mark II was registered to the current vendor in May 2013 and since acquisition has been ridden sparingly, spending most of the last 2½ years in dry storage. The machine was last taxed for the road in April 2014. It should be noted that the frame and engine numbers are transposed in the accompanying V5C registration document.