The Corsa is Polini’s revised 70cc sport cylinder. Extreme port timing, polished exhaust port and increased primary compression result in up to 2–3 hp more power as compared to standard 70cc cylinders. The piston is equipped with a chrome and a grey cast iron piston ring. To be able to exploit full power, the cylinder should be used in conjunction with a sport exhaust, or better still a racing exhaust such as Stage6 or Polini ForRace. Also necessary is at least a 17.5 carb to ensure sufficient internal cooling. Compatible with: - Aprilia: SR 50 Min.AC 94-_S - Mbk: Booster 50 euro 0-1_S, Booster 50 euro 2_S, Stunt 50 euro 0-1_S, Stunt 50 euro 2_S - Yamaha: BW's 50 euro 0-1_S, BW's 50 euro 2_S