NCY Transmission Power Pack for 125cc – 170i GY6 Scooters, ATVs, and Go KartsINCLUDES: Ultralight gold specially coated overdrive variatorNEW UPGRADED Ultralight Aluminum outer drive faceUltralight large shoe racing clutchNEW Ulltralight drilled & vented clutch bell (99 grams lighter than previous NCY Bell)Dual range secondary slider18x14 10gram, 11gram, and 12 gram roller weights1500 RPM compression springBall bearing compression spring seatThis NEW AND IMPROVED Super Trans Kit is one of the best dollar-for-dollar bolt-ons to improve your bike! Quicker acceleration, higher top speeds, and makes your CVT the smoothest operating trans in town! From rapid down shifting to slow cruising, this thing is smooth. Ultralight balanced components, oversized wear pads, and state of the art polytetrafluoroethylene (PTFE) coatings ensure superior performance and long service life.**Recommendations: Use a new belt with this kit. Use graphite or Moly grease when assembling**