LOT 209

The Bob Howard Collection 1955 Ariel 995cc Square Four 4G MkII Registration no. HDY 539 Frame no. PS304 Engine no. GL292

Sold for £8,970 inc. premiumLot to be sold without reserve

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Lot 209

The Bob Howard Collection, 1955 Ariel 995cc Square Four 4G MkII

The Autumn Stafford Sale - The Classic Motorcycle Mechanics Show|12 October 2025, 11:00 BST|Stafford, Staffordshire County Showground

The Bob Howard Collection
1955 Ariel 995cc Square Four 4G MkII
Registration no. HDY 539
Frame no. PS304
Engine no. GL292

Designed by Edward Turner, creator of Triumph's legendary Speed Twin, the first Ariel Square Four appeared 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 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 characterful machine retains an enthusiastic following and is highly prized.

Currently displaying a total of 79,153 miles on the odometer, this MkII has belonged to our vendor since 10th April 2023. Following a period of inactivity (the last MoT expired on 22nd June 2024), this motorcycle will require recommissioning to a greater or lesser extent and thus is sold strictly as viewed (inspection highly recommended). Offered with a V5C document, and a substantial quantity of invoices and other paperwork.
Offered with key

Footnotes

All lots are sold 'as is/where is' and Bidders must satisfy themselves as to the provenance, condition, age, completeness and originality prior to bidding.
Please see the Auction Information and Guide for Buyers at the top of the main sale page, for bidders' obligations. The Autumn Stafford Sale

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This Lot will be auctioned on Sunday 12 October, with the auction starting at 11am GMT.

Additional information

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