Tuesday 14th April 1891

Joseph Day applied for a British patent for his of the valveless two-stroke engine. On the original design there were two flap valves – one in the inlet port, where you would probably find a reed valve on a modern two stroke, and one in the crown of the piston, because he did not come up with the idea of the transfer ports until a couple of years later. He made about 250 of these first two-port motors, fitting them to small generating sets, which won a prize at the International Electrical Exhibition in 1892. The extremely widely used crankcase-compression two-stroke petrol engine, was widely used for small engines from lawnmowers to mopeds and small motorcycles.