Cycling had been a popular pastime and a relatively practical means of transport for about 40 years before the arrival of the Wall Autowheel in 1912. This consisted of a 118cc single-cylinder engine with atmospheric inlet valve and side exhaust valve, mounted in a sub frame that attached to an everyday pedal cycle at three points, that engine driving to its own integral wheel, thus effectively creating a three-wheeler. It was marketed by Auto-Wheels Limited. The Smith Motor Wheel and Briggs & Stratton Motor Wheel were developments of the Wall Autowheel. The company was backed by Arthur Conan Doyle, author of Sherlock Holmes.
