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(William Herbert) Percy Riley
1880 Born, son of William Riley, (Junior) and his wife Emma
1898 Percy Riley began to dabble in automobiles. He built his first car at 16, in 1898, secretly, because his father did not approve. It featured the first mechanically operated inlet valve.
1901 Living at Holly Bank, Radford Road, Coventry with parents, aged 20, an engineer mechanic 
At the age of 20 Percy was already a practical and ingenious engineer. At first, he simply supplied engines for Riley motorcycles, but his company soon began to focus on four-wheeled automobiles.
1903 Percy patented a method of mechanical valve operation. 
Percy Riley's inventiveness led to several more patents on various key components of the car, including steering, clutches and brakes, gears, driving axles and crankshafts, and engines, but his most important invention was the development of an easily detachable wheel for motor vehicles. Not only did such wheels become a major part of the Riley Cycle Company's business but the design was licensed to 183 manufacturers worldwide.
1913 Percy was joined by three of his brothers (Victor, Stanley, and Allan) in a new business focused on manufacturing entire automobiles. This Riley Motor Manufacturing Co was located near Percy's Riley Engine Co. The first new model, the 17/30, was introduced at the London Motor Show that year.
Founder of the Riley Car company