Vespa PX125 150 GTR Sprint Veloce POLINI 177cc 180cc Cylinder Kit Iron

Vespa PX125 150 GTR Sprint Veloce POLINI 177cc 180cc Cylinder Kit Iron

• cast iron
• 7 ports
• Ø 63,0mm
• stroke 57mm
• 2 piston ring(s)
• with cylinder head

The Polini 177 iron kit is the classic racing cylinder for the PX and Sprint 3 channel engines.
A very early high torque makes it an allround cylinder for almost all needs. It is ideal for the so called "plug-in tuning", i.e. simply changing the cylinder without modifying the rest of the engine.

After the conversion everyone is amazed how powerful a Vespa engine can accelerate. The beary torque turns every steep mountain into a plain.
The only disadvantage is that the Polini doesn't turn very much. At about 7000 rpm the engine runs a little bit in front of the wall, a longer transmission ratio by means of another clutch pinion is recommendable in any case. Then the Polini easily exceeds the 100km/h mark and the gears can be pulled much longer.

If you are only driving in the city you can use the 24/24SI carburetor of the 200cc models. The carburetor should be driven with a 160 main air jet and a BE3 mixing tube. If the engine still tends to slim down in the upper rpm range a 140-150 main air jet should be fitted.