The POLINI RACING is the secret king of the 75cc cast iron class and makes the front wheel rise! POLINI entices with attributes that are otherwise only to be found in the 125cc long-stroke segment.
Highlights such as a generous exhaust with 2 auxiliary exhaust channels, a high quality ASSO piston and 6 transfer port channels are enough to make your mouth water. In addition, the POLINI 75cc RACING cylinder is painted black for protection against corrosion and for better heat dissipation.
Conclusion: Only short-stroke cylinder with auxiliary exhaust porting, scores points with its extra performance, a higher compression of 11.9:1 and the 6 powerful transfer ports.
Cast iron/ 47mm bore/ 6 transfer ports/ 74.60cc
Cast iron cylinder, stroke 43mm, 6 transfer ports, coated piston with 2 piston rings and cut-out, a main exhaust with 2 auxiliary exhausts, 6mm exhaust studs, original POLINI cylinder head is included in delivery, compression 11.9:1, incl. gasket set. Jets should be adjusted. Fits on all Vespa 50/PK/XL/XL2 models, except PK automatic. Transfer ports match the originals, casing must not be modified.
SIP-TIP: Adjusting the main jet and a new spark plug is a must. Recommended transmission here is at least a 3.72 primary. Optimal with 16/ 16 carburettor, original exhaust with a fat manifold or the SITO banana. After a little modification of the cylinder, a 19/ 19 carburettor can also be used in combination with a POLINI racing exhaust with no problem!
SIP-Community User "Marco_r3000":
"Polini are simply good. Everything fits with them, and it is just reliable. Easy to run in and with the right power. Combined with Polini exhaust, larger drive cag, 19 carburettor, racing air filter and an HP4 you have really got something there."