Polini's entry-level Contessa 72cc Big Bore kit is relatively easy to install, tune, and improve the performance of your Genuine 50cc, Yamaha Zuma or BWS 50cc, and other bikes with 2T horizontal Minarelli engines. It's the ideal starter big bore kit for someone looking to get significant gain without excess tuning time.

Specifications:

• Aluminum piston: 47mm
• 2 piston rings: 47mm
• 10mm wrist pin w/circlips
• Cast-iron cylinder
  
• 2 exhaust studs: 6mm

Compatibility:

NOTE: It's important to break in your big bore kit properly. We recommend riding 200 - 300 miles before running the bike at full throttle for an extended period of time. 

About Polini:  For over 50 years, Polini has stood unparalleled in the racing and tuning scene.  Polini has powered both off-road and road racing legends to multiple MXGP and MotoGP world championships including the legendary Valentino Rossi.  Polini sets the standard for high-end tuning and top-quality performance components.

Made in Italy.

This product is intended for off-road use only.

This product is not intended for use on public roads or land.

This product is not legal for use in California on pollution-controlled vehicles. Check local laws before installing.

*Performance upgrades are considered racing parts and are not covered by warranty.

WARNING: California's Proposition 65