Vintage motorcycle “Ariel Square Four Mk1”Brand: Arielmodel: Square Four Mk1country: United Kingdom - Birminghamyear: 1950condition: preserveddisplacement: 995 cc (bore and stroke 65 x 75)engine: four-cylinder "square"gearbox: four-speedAlready known as a bicycle brand in the mid-nineteenth century, the evocative name of Ariel, Shakespearean spirit, reappeared in 1901 linked to the first motorcycle of a long series, which mounted a 211 cc engine. The Birmingham factory produced many single-cylinder and some twin-cylinder, until 1931 when, designed by Edward Turners, the "Square Four" was born, an engine that later became legendary. With a double parallel crankshaft and four cylinders arranged in a square, its design remains unique in the world motorcycle scene.This engine