The improbable LAMBRETTA GP 250cc
(photo: Phil Aynsley)
After World War II, in the late 40s of the last century, two Italian industrialists, Ferdinando Innocenti and Enrico Piaggio had a similar vision regarding the need to create an individual and cheap means of transport that could serve the needs mobility that the economic reorganization imposed. The interpretations they made of the possible solution were quite similar and gave rise to two brands LAMBRETTA and VESPA that became a school and became universal. Both brands are known for this very reason, but it is curious that LAMBRETTA, trying to prepare for an eventual entry into other motorcycle segments, has produced a prototype destined for competition! Although MOTO GUZZI is synonymous with a 2-cylinder engine in V 4T transverse with overhead camshaft, the Mandello del Lario brand only introduced this concept in 1965!
(photo: Phil Aynsley)
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In fact, it was LAMBRETTA that, in 1951, presented this solution, at the time, innovative and even revolutionary, at the Milan Motor Show, at a time when Italian production was still far from the technical complexity of multi-cylinder engines! Giuseppe Salmaggi was hired as “project leader” and gave birth to this innovative bike. The 90 degree V-twin engine had the crankshaft mounted longitudinally, this arrangement placed the cylinders out, which facilitated cooling, a bore/stroke ratio of 54mm x 54mm resulted in a displacement of 247cc that delivered 29CV (21KW) at 9,000rpm and allowed a maximum speed of 170km/h. The whole project was full of ingenuity, the heads were produced in aluminum and had two valves controlled by triple springs, instead of the usual double ones, controlled by a camshaft that worked in ball bearings unlike the usual bushings, lubrication was by oil powered under pressure, the camshaft was driven by a shaft through bevel gears, the front part of the casing, in the form of a bullet, contained a magnetic flywheel, behind the engine, a gearbox with 5 ratios was mounted. It's a little strange that the final drive was in charge of a gimbal instead of a chain that would be lighter!
(photos: Phil Aynsley)
The complete bike was just as interesting as the engine. The chassis consisted of a large diameter tube (backbone) that curved backwards until it found steel plates where the engine was anchored. The front suspension was given a conventional telescopic fork, while the rear was configured as a torsion bar with adjustable friction dampers. The brakes were made of aluminum alloy hubs, the 21” wheels and PIRELLI tires completed the top cocktail. The bike was presented in Milan in a final version, this did not come as a surprise because it was known that, in the previous months, several test sessions had already been carried out at a local track. The bike was developed over the next two years and the final version evolved into a dual overhead camshaft distribution having abandoned the dry sump and an oil tank being located at the bottom of the engine, the original rear suspension was abandoned. and replaced by two hydraulic shock absorbers, a detail of great category for the time, double magnets were also explained. Unfortunately, this masterpiece by LAMBRETTA never returned the ingenuity and effort put into its construction and, in 1953, the project was abandoned, along the way, had been hired as test pilot Cirillo “Nello” Pagani, 125cc World Champion at the controls of a MONDIAL, and despite two unsuccessful participations in GP (France and Switzerland) with Romolo Ferri at the controls, the development did not follow the genius of the device. For history, the idea of visionary architecture must subsist, which, to this day, is still a success at MOTO GUZZI!
(photo: Phil Aynsley)
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