the new engines:
3 valves state of the art


3 valves


The evolution of Vespa has always maintained the concept of form/function as a core element. Development over time has taken place in observance of some indispensable and consolidated technical and stylistic choices, constantly innovating its content.

A new engine makes its début on the Vespa LX and Vespa S, rightfully considering the cutting-edge in this segment and destined to last over time with its excellent performance and minimum consumption and emissions levels.

With the new and highly technologically advanced 125-150 4Stroke 3 Valve power train, Piaggio once again opens a window to the future of motoring technology.

It is a single cylinder 4 stroke air cooled engine with 3 valves (2 intake and 1 exhaust) single overhead cam and electronic fuel injection. It was designed and built in the Pontedera plant, in some of the most advanced research & development centres in the world, with the goal of increasing performance and fuel economy and lowering polluting emissions. In order to obtain greater performance a scrupulous study to decrease friction and improve fluid dynamics was conducted.

The new crankshaft, with reduced button and bench capacity, the pivoted cam axle on the bearings and roller rockers have made a significant improvement in operating friction, all to the benefit of performance and fuel economy. The bore and stroke values are new (respectively reduced and increased), to the benefit of torque and acceleration response. In the search for the best performance/fuel consumption ratio, the 3 valve timing solution is the most effective because it improves intake, increasing engine efficiency compared to conventional 2 valve engines. The innovative timing system thereby lets us improve the fuel mixture loading movements in the cylinder; the combustion process is further refined by the new spark plug position which simultaneously ensures improved cooling of the components in the head, as well as simplified maintenance.





The cooling system was the object of careful analysis, even through thermo fluid dynamic simulations, in order to further improve performance and thereby obtaining a significant reduction in mechanical noise and absorbed power. The fuel injection system is extremely advanced, with a continuous cycle automatic idle management and continuous cycle fuel mixture management with the introduction of an efficient Lambda probe. A latest generation ECU takes care of managing advance mapping, fuel mixture and timing.


The new free wheel electric starter, more quiet and efficient, goes perfectly with an engine so rich with technological content. Also, the automatic dry centrifugal clutch has been calibrated with the goal of maximizing performance and fuel economy at low speeds. The 3V also has the important advantage of weighing less than its 2V predecessor.




The 3 valve technology in the Vespa LX and Vespa S 125 and 150 cc engines provides clear improvement of performance compared to the previous generation engines: maximum power of the 125 is improved by 7.1%, and maximum torque by 10.3%; acceleration time from 0 to 60 metres drops 2%, and top speed increases by 2.2%. The same is true of the Vespa LX and Vespa S 3V 150 cc: maximum power and torque increase respectively by 6.3 and 7.8%, with a decrease in the time it takes to go from 0 to 60 metres to the tune of 5% and a 3% increase in top speed.

fuel economy


Despite the significant performance enhancements, fuel economy is drastically improved from the previous 55 km/l to 50 km/h (about 30% better compared to previous generation engines), while service intervals are now extended to every 10,000 km. The new 3V engine allows for extremely contained operating costs: in one year of use (during which the Vespa customer rides an average of 4,000 km), this allows a savings of about 34 litres of fuel which corresponds to an extra 1,500 km.