Description
National Motorcycle Museum | Solihull, West Midlands
26th Mar 2025 - 9:00AM
1932 Ariel Square Four
Rare overhead cam model
Estimate
£9, 000 - £11, 000
Registration No: GW 7641
Frame No: T1559
MOT: Exempt
Early overhead cam 600cc model
Unique 'square four' engine layout
Supplied with a dating letter and a V5C
Like many British motorcycle companies, Ariel began producing bicycles in the late 1800s eventually progressing onto motorcycles in 1902. After a typically rocky few years for manufacturers in the early part of the century, the company was bought by Jack Sangster from the receivers at a bargain price in the early 1930s. The company was renamed Ariel Motors (J. S.) Ltd, and promptly resumed production in a new factory in Selly Oak Birmingham. One of their first bikes produced was the Ariel Square Four designed by Edward Turner, who at the time was looking for work and showing drawings of his engine designs to various motorcycle manufacturers. The design was rejected by BSA but adopted by Ariel, becoming their prestige model for the next 30 years. In the days of predominately single-cylinder engines a square four layout was very advanced and the bike stayed in production until the late 1950s. The engine was initially a 500cc with overhead cams and was essentially a pair of across-frame parallel twins joined by their geared central flywheels before being bored out to 600cc in 1932. A very expensive engine to produce, it was given a major revamp in 1939 to become an easier to manufacture 1000cc motor with overhead valves (OHV) in place of the overhead cams (OHC).
This beautiful Square Four has been part of an enthusiast's small private collection of this rare and extremely collectable model. According to records supplied by the Ariel Owner's Club, it was dispatched to Hackford Motors in London on Tab No. 11554 fitted with engine no. T701 and first registered in early March 1932. The bike has been restored over recent years with the crank overhauled by Alpha Bearings, a new oil pump fitted together with a new pair of period correct tires. The innovative Ariel Square Four remains unique in the history of motorcycling, with only Suzuki many years later producing a very different two-stroke Square Four 500cc model. Promoted as a true 'gentleman's motorcycle, it is now highly prized by discerning enthusiasts, especially the early overhead cam models. Supplied with letters from the owner's club and a V5C, this bike would grace any collection.
