1951 Ariel 998cc Square Four 4G Mk1
Registration no. OSU 846
Frame no. SC474
Engine no. RD442
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 1. To date, the innovative Ariel Square Four remains unique in motorcycling history; a true 'gentleman's motorcycle', this refined yet characterful machine retains a loyal following and is highly prized by discerning enthusiasts.
Partly restored by a previous owner circa 1998, when the engine was rebuilt, this Ariel Square Four benefits from recent further refurbishment. The latter included rebuilding the wheels with new rims and spokes; hubs enamelled by Nunns of Surbiton; fuel tank and wheels repainted in red (from black) and the speedometer overhauled. Previously registered 'FPM 814', the machine is described as in generally good condition and offered with old-style logbook, sundry invoices, a quantity of expired Mots and Swansea V5.
- There is no dating certificate with the machine.