Description New performance GY6 roller weights for Gy6 125cc, 150cc engine. Size:?1814 mm, Weight: 12.5 gram, Package: 1set, 6Pcs "Lighter rollers weights require higher RPMs to push the rollers outward through centrifugal force and begin changing your CVT's gear ratio. Heavier roller weights need lower RPMs to begin changing gear ratios. Lighter roller weights = faster take-off acceleration, lower top speed. Heavier roller weights = slower take-off acceleration, higher top speed. For stop-and-go city driving, lighter roller weights may be preferred. For long-distance highway driving, heavier roller weights may be good