1955 Ariel 1,000cc Square Four MKII

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

1955 Ariel 1,000cc Square Four MKII
Frame no. GM1101
Engine no. GL243

*Iconic Square Four model
*Well kept example through long-term ownership

"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.

In 1937 a total redesign saw the Ariel 'Square Four' re-emerge as the Model 4G, with 995cc overhead-valve engine, making it an even more enticing prospect for sidecarists. 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 on the revised 'Mark I', which was now capable of 90mph-plus. 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'.

Not much is known about this Square Four's history but having been in long term ownership with the late vendor, it will need recommissioning to a greater or lesser extent having been on static display in the private museum of the late vendor, a wonderful opportunity to acquire a piece of Ariel's outstanding history.

Saleroom notices

Please note that Frame GM1101 is dated to 1957, not 1955 and the title will be in transit.

Additional information

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