Ariel
1955 Ariel Square Four
Here we are pleased to offer a very nicely presented 1955 Ariel Square Four
For riders and collectors who appreciate engineering innovation, the Ariel Square Four stands apart. It was originally engineered by Edward Turner in 1928, featuring a distinctive “square” engine layout—two parallel twin blocks paired together and connected via central gearing to form a compact four-cylinder unit. This design minimizes engine length while maintaining smooth power delivery and balanced operation.
Powered by the later 997cc OHV four the layout reduced torsional vibration and allowed for a shorter crankshaft length compared to conventional inline-four engines.
Fitted with the later plunger rear suspension and telescopic front forks, providing improved ride compliance over earlier girder designs
The Square Four’s compact multi-cylinder design was ahead of its time, offering a rare combination of smoothness and torque in a pre-war and post-war motorcycle
This example is in exceptional condition and has been maintained to an unusually high standard while preserving originality.
A machine defined not just by its heritage—but by the engineering principles that set it apart.
£15,000
