1957 Ariel 1,000cc Square Four MKII

The Amelia Island Auction|3 March 2022, 10:00 EST|Fernandina Beach Golf Club

1957 Ariel 1,000cc Square Four MKII
Frame no. GM127
Engine no. NML1987

*Evolution of the Ariel 4G
*Same owner since 1989

Designed by Edward Turner, creator of the trend-setting 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' Mark II 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 big motorcycle with its mighty 61 cubic inch overhead valve engine handles like a lightweight - goes like a bomb! In a road test report "Cycle" Magazine says: "Incredible! - the standard Ariel Four in full road trim repeatedly ran the ¼ mile drag in 12.9 seconds!" - Treat yourself to a new sensation in motorcycling - ride the Ariel Four!" Here is what you could read on 1957 US Advertisements for the Ariel Square Four.

Offered with a purchase receipt to the late vendor from 1989, little history is known of this high desirable model but it will need recommissioning to a greater or lesser extent having been on static display at the late vendors private museum.

Saleroom notices

Please note that the engine number is actually NML 1287 and Frame number GM 1276.

Additional information

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