Cylinder polini evolution reed 152cc diameter 60,stroke 54 for vespa 125 primavera/et3

Polini Motori has produced a new Evolution kit with a reed valve induction in the
cylinder for the 125 Vespa Primavera ET3.
This creates an engine that is really powerful in every kind of driving condition and
during the races.
The kit with "Reed Evolution" induction in the cylinder comes with: cylinder, piston,
head, reed valve intake manifold and a gasket kit.
The cylinder is cast in aluminium with bore of 60mm.
The liner with Nickel-Siliceous coating improves the piston sliding, its resistance to
wear and abrasion. The transfer ports are designed for racing. It has 6 transfers.
The transfer has a central bridge for a better exhaust gas scavenging.
The head is cast in one piece only and some fins have been made under the head
plane in order to improve the heat dissipation. The compression ratio has been
designed to achieve the best performance.
The piston is cast in aluminium and it has one S10 chromed cast iron ring. After its
working the piston has been covered with special molybdenum-bisulphide coating that
improves the piston sliding during the running in period.
The reed valve has 6 carbon flaps of 0,4 mm thickness and the geometry of the flow
guide allows it to improve of the air-petrol mixtures incoming speed.
The intake manifold has been developed to be matched with the Dell’Orto VHSB Ø34.
To be able to fit this cylinder kit, bore the crankshaft housing in the case. It is
necessary to change the original crankshaft with a new Polini one, part no.
210.0070 .By fitting these parts you achieved a 152cc of displacement according to
the sprint scooter races’ rules.
To achieve the best performance fit the Polini Evolution 2 muffler, part no. 200.0291
Cylinder kit part no.: 140.0227