Cylinder -POLINI cast iron 133 ccm Racing- Vespa PV125, ET3 125, PK125

Polini 133 cast iron - reworked classic for Vespa 125

Polini has very gently reworked the legendary 133. This was all that was necessary for the cylinder, which is very sophisticated by design. The main change concerns the cylinder head. The 57 mm bore has been retained, which means that 130 cc is available with a 51 mm shaft and an impressive 138 cc with a 54 mm shaft. The layout of the cylinder is unchanged and is determined by the six transfer ports.

The piston is made of die-cast, which gives it very good durability and low weight. The new head is made of cast aluminum with a high silicon content. It also has additional cooling fins on the underside. This means that heat is dissipated much better, both from the cylinder itself and from the head. The compression has also been slightly adjusted. The new copper gasket not only conducts heat better, it also contributes to a significantly better seal between the cylinder and head.

Conclusion: A classic made even better!