You don’t see many of these on the road…  You don’t see many for sale either!  This one is coming up for auction at Bonhams in Paris.  It’s a very rare 640cc Megola.  I’m not sure exactly what year this example is, but they were made in very limited numbers (around 2000) from 1921 to 1925.  Made in Munich, Germany, the name Megola is derived from the names of the designers, Meixner, Gockerell and Landgraf.

The obvious feature making this classic motorcycle stand out from the crowd is the five cylinder side-valve rotary engine mounted within the front wheel.  The wheel axle was formed by the crankshaft that stayed stationary as the cylinders rotated with the wheel.  The bike had no clutch or neutral gear, so the only way of coming to a stop was to stop the engine and then to push start it again when required. The high torque of the engine allowed it to accelerate from a standstill to full speed (of ar0und 55mph) with a single gear.  The frame was made of welded and riveted sheet metal. The tube of the front wheel had a special design: the tube was an open circle (rather like one of those modelling balloons), so it could be changed without taking the front wheel (and the engine!) out.

Only a small number of these are known to exist in a rideable condition.  This vintage motorcycle was restored in 1990 and is estimated to sell for €145,000-200,000.