In 1930, this 499cc single-cylinder was capable of over 100mph and taking wins at road races like the Ulster Grand Prix and Isle of Man TT. The Rudge Ulster did that by employing ahead-of-its-time technology like radial valves (still trotted out as an innovation in 2011) to produce 45bhp. Like much advanced thinking, the Ulster didn’t mesh well with its times, arriving during the Great Depressio...

In 1930, this 499cc single-cylinder was capable of over 100mph and taking wins at road races like the Ulster Grand Prix and Isle of Man TT. The Rudge Ulster did that by employing ahead-of-its-time technology like radial valves (still trotted out as an innovation in 2011) to produce 45bhp. Like much advanced thinking, the Ulster didn’t mesh well with its times, arriving during the Great Depression when expensive race-replicas needed to give way more workaday machinery. That didn’t stop music label EMI from stepping in, it attempted a revival of the Rudge Brand and Ulster bike in the late ‘30s before concentrating its efforts on developing radar technology for WWII.

According to Webb’s, which will auction the bike on Wednesday, “The technology Rudge adopted was inspired by the demands of WWI which had pushed engineering to its limits on a daily basis. Rudge was chasing a dream – to build the finest, fastest roading single of the day. The engine boasted a unique pent roof combustion chamber, with the radially set exhaust valves giving better top-end gas flow with the twin exhaust pipe. It had an innovative rocker arm arrangement, an aluminium bronze cylinder head and a pressed roller-bearing crankshaft. The Ulster also utilised an in-house-designed four-speed gearbox.”

During its struggle to develop the Ulster, Rudge-Whitworth went into receivership and was taken over by one of its creditors. That company was Gramophone Co. Ltd, which would later change its name to EMI. They added a cast alloy cover to the exposed valve gear in order to protect it from weather and debris, hopefully making the Ulster more practical. The story ends there with the outbreak of WWII. EMI would go on to become a major record label while diversifying its manufacturing wing into more recession-proof products like typewriters and sewing machines. The Rudge brand would go on to manufacture knock-off wire wheels for British sportscars well into the 1960s.

Webb's