James Starley

Bicycle wheels and the differential. A Coventry sewing-machine maker, Starley turned the city into the centre of the cycle trade. With William Hillman he built the Ariel high-wheeler in 1870, and in 1874 patented the tangent-spoked wheel, whose angled spokes carry driving and braking forces far better than radial ones and are still used today. His 1877 differential let a tricycle's two wheels turn at different speeds on corners.