Megola

The Megola was a German motorcycle produced between 1921 and 1925 in Munich. Like Bimota, the name is a portmanteau derived loosely from the names of its designers Meixner, Cockerell, and Landgraf.

The Megola had a unique design, laid down by Fritz Cockerell in 1920, using a rotary engine mounted within the front wheel. The engine contained five cylinders with side-mounted valves, each of which displaced 128cc, with a bore/stroke of 52x60mm, and a total displacement of 640 cc (39 cu in). The 5 cylinders rotated around the front axle at 6x the wheel speed; thus while the cylinders were at maximum of 3600rpm the front wheel was turning at 600rpm, or roughly 60 mph (given the wheel diameter). A hand-controlled butterfly valve was located in the hollow crankshaft to regulate throttle. Power output was a modest 14 bhp (10 kW) but was applied directly to the wheel. This arrangement produced a very low centre of gravity and provided for excellent handling.

The engine was very flexible, lacking both a clutch and a transmission. Starting it required a person to either spin the front wheel while the bike was on its stand, or to push-start. The cylinders could be disassembled without having to remove all the wheel spokes in order to service the engine. The tires were tubed with the front inner-tube being a circular sausage shape rather than a complete doughnut-like torus shape, so that it could be changed without removing the wheel and engine. The box section frame contained the main fuel tank which fed by gravity a smaller tank mounted on the axle. The front suspension consisted of semi-elliptical springs.

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