NCY Clutch Compression Spring also known as an NCY Contra Spring.  Compression / Contra springs do a couple of things. First, they supply the pressure to engage the belt. They also determine the rate at which the CVT transmission changes from low to high gear. A 1000rpm spring will go into a higher gear sooner than a 2000rpm spring.

This NCY 2000 rpm compression/contra spring will fit:

Yamaha Zuma 2T 50cc
Most Minarelli applications

Specifications:

• 2000 RPM Compression Spring
• Wire Diameter: 4.0mm
• Inner Diameter: 44.0mm
• Length: 108.0mm 
  

About NCY:  NCY stands as the premier provider of aftermarket performance components for leading scooter brands such as Honda, Yamaha, Genuine, Vespa, Piaggio, SYM, Lance, KYMCO, and GY6/QMB powered scooters. Established in 1997, NCY adheres to rigorous quality standards and holds ISO 9001 certification. 

NCY performance parts are made in Taiwan.