Contra Spring Polini 3,9mm Piaggio Zip

Polini offers contra springs for most scooters and maxi scooters. In general, there are various approaches to setting the variator as precisely as possible in order to get the best performance out of an engine.

• Brand: Polini
• SKU: P243.031
• Availability: In stock

Contra springThe contra spring, or torque spring is part of all scooters and mopeds with CVT transmissions.function of torque springThe contra spring is located between the rear pulley and the clutch. As soon as you accelerate and the engine revs up, the spring is released by centrifugal force. This causes the front pulley to open, which in turn causes the V-belt to move outward on the CVT front pulley. The transmission ratio changes in favor of higherspeed. When the scooter slows down and the engine speed is reduced, the torque spring is compressed again and the V-belt returns to a lower position on the front pulley.soft or hard contra spring?The choice of torque spring depends on different