The Moto Guzzi 125 cc prototype was a prototype for a light motorcycle that was developed during the Second World War, but never went into production.
During the war a law was passed in Italy that made it possible to use motorcycles up to 125 cc without license plate. Moreover, there was a need for economical means of transport, because all vehicles, even trucks and tanks, drove on petrol at the time and that was scarce. That is why Moto Guzzi started working on two prototypes: a clip-on motor, the Colibrì, that could be mounted on the back of a bicycle, and a light motorbike. 125 cc prototype
The 125cc model was a smooth-looking motorcycle that actually followed the familiar lines of the heavier Guzzi single-cylinder, but was constructed simpler and above all cheaper. The bicycle part consisted of a double cradle frame, which was mainly made of sheet steel and even the parallelogram fork was made of sheet steel, as well as the rear swing arm. The machine did get rear suspension, but no longer the well-known Moto Guzzi system with coil springs in a tube under the engine block. A cantilever system was used for the prototype, with two coil springs above the swingarm axis. Simplex brakes were applied before and after. The engine was (for Guzzi notions at least) ahead of its time: the tumblers and valve springs were enclosed, and that happened with the other models until 1948. Because the valves were at a fairly large angle, the cylinder head split into a V- form. Both pushrods also formed a "V". Furthermore, the engine was built as one was used to at Moto Guzzi: a reclining single cylinder with a dry-sump lubrication system. He had three gears and a chain drive to the rear wheel. Although the prototype was completely finished, the machine never came into production. That was probably due to the price and the demand from the customers. After the war it was even cheaper, and the companies that made auxiliary engines and "moto leggere" (light motorcycles) shot up like mushrooms. Moto Guzzi released an even lighter motorbike in 1946: the Motoleggera 65.
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