POLINI 75 cc CYLINDER KIT - VESPA 50 - APE 50 - Ø 47 mm

Polini cast iron cylinder Ø 47 mm with 75 cc displacement, designed as a direct replacement for the original cylinder on Vespa 50 N, 50 L (Lusso), 50 R (Rinnovata), 50 Special, 50 Revival, 50 PK, 50 PK S, 50 PK XL and Ape 50.

Compared to the standard cylinder kit, this unit features revised transfer ports that provide improved performance and enhanced engine responsiveness, delivering approximately 7.5 HP. It is compatible with the original crankshaft with 43 mm stroke, with no need for replacement.

The kit is supplied complete with cylinder head and gaskets and is ready for installation. Assembly is straightforward and does not require any specific machining, making it a reliable solution for riders seeking improved performance while maintaining excellent long-term durability. Polini machining ensures high strength, good low- and mid-range torque and controlled fuel consumption.

For higher performance levels, the kit can be combined with a racing crankshaft, larger carburetor, variable-advance electronic ignition, longer gear ratios, reinforced clutch and a suitable exhaust system.

Baseline carburetion settings (may vary depending on the configuration):
SHB 16.16: main jet 66–68
SHB 19.19: main jet 80–82
PHBL 24: main jet 72–76 – idle jet 50 – atomizer AQ264 – needle D22
PHBL 24 reed-valve: main jet 100–102 – idle jet 64 – atomizer AQ264 – needle D22

Recommended spark plug: Champion L78C, NGK B8HS, Bosch W3AC, Denso Iridium IWF27
Recommended ignition timing: 17°

Product intended for racing and sporting use only. Not homologated for use on public roads.