POLINI Cylinder Kit ⌀47mm Pin 12mm Aprilia / Italjet / MBK / Yamaha 50cc 90-19

Polini Motori presents the new range of kits for Minarelli engines mod. CY, MY, CW with Ø 12mm piston pin.
This feature lets an increase in terms of liability of a parts that its under long stress. The cast iron cylinder with 6 transfers is machined with tools that grant high quality products, with sliding walls with controlled roughness for a better cylinder-piston sliding. The exhaust diagrams and the transfers have been designed to work in line both with the Polini Original and Scooter Team mufflers. The piston is mad of special alloy with high siliceous percentage with the aim to grant the maximum resistance to high temperatures. The piston rings made of spheroidal cast iron, highly resistant to wear, rebored and lapped. The head is made of special aluminum light alloy with high coefficient of heat exchange. The combustion chamber has been completely redesigned for a high compression ratios with high turbulence. Polini cylinders kits for Yamaha Minarelli engines must be installed together with the crankshafts with connecting rods for Ø 12 piston pins.
Polini cylinder kits for Yamaha Minarelli engines Ø 12:
166.0074/12
166.0076/12
166.0083/12
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