Vespa PX 125 [1978-2016] - Cylinder kit gray cast iron Ø 63

MALOSSI cylinder kit gray cast iron Ø 63 for Vespa PX 125

The MALOSSI cylinder kit gray cast iron Ø 63 is intended for the Vespa PX 125 in the entire model range from 1978-2016. The bore of 63 mm and the stroke of 57 give a displacement of 178 cm3. The revised internal fluid dynamics with profiled overflow channels specifically align the gas flow and support uniform flushing.

Function and construction

The inlet channels promote a controlled flow with high turbulence. The rear overflow channels feature a double slope (1-2) profile, while the outlet is redesigned for gas flow towards the exhaust. The two-ring piston Ø 63 is designed for high operating temperatures. Its shape supports even guidance in the liner and reduces the play between piston and cylinder.

The cylinder head features a hemispherical combustion chamber shape, an inclined yet central spark plug position and revised cooling fins. Two centering bushings support the coupling of the head and cylinder; the separation is done by an O-ring.

Technical data

• Material: aluminum
• Diameter Ø: 63 mm
• Displacement: 178 cm3
• Stroke: 57
• Piston compression: Racing
• Piston rings: 2
• Overcurrent channels: 6
• Compression ratio: 1:10.5
• Cylinder head: hemispherical
• Spark plug: IW 27
• Recommended carburetors: Si 24/24, phbh 30
• Area of use: urban/sport
• Processing level: Easy
• Performance range: 14/22

Vehicle assignment and notice

Suitable for Vespa PX 125, built between 1978 and 2016. The product is intended exclusively for competitions at designated venues in accordance with the regulations of the relevant sports associations. No liability is assumed for improper use.