Dr. Pulley 20x12 Sliding Roller Weights: Yamaha, Kymco

Unlock the full gear range your CVT was designed for. Dr. Pulley 20x12mm Sliding Weights replace the flat-spotting round rollers in your variator with a patented non-round geometry that lets the variator retract further for a lower starting ratio and extend further for a higher top-speed ratio — delivering faster launches and lower cruising RPMs without touching your belt or variator. Choose your gram weight to dial in exactly the performance character you want.

Performance & Engineering Advantages

• Eliminated Flat Spots: The sliding shape prevents the uneven wear and notching common with circular weights, ensuring consistent shifting performance for thousands of miles.
• Maximum Gear Range: Pushes the variator plate further than OEM specs, providing a tangible increase in top-end speed on open roads.
• PA46 Tribological Composite: Oilless, self-lubricating nylon that resists heat and friction better than standard rollers — no grease required.
• Precision Gram Tuning: Available in 8.5g through 12g (in 0.5g increments) to perfectly match your CVT engagement to your riding style or exhaust setup.

Technical Specifications

• Dimensions: 20mm (diameter) x 12mm (width)
• Material: Oilless PA46 Tribological Composite
• Shape: Patented Sliding Geometry
• Available Weights: 8.5g, 9g, 9.5g, 10g, 10.5g, 11g, 11.5g, 12g
• Quantity: Set of 6

Fitment Guide

These 20x12mm weights are a direct performance upgrade for many 125cc–300cc scooters and go-karts:

Tuning & Installation Tips

• Orientation is critical: Ensure the Dr. Pulley logo/flat side faces the correct direction in the variator ramps — incorrect installation will hinder performance and can cause damage.
• For better acceleration: Go 1–2 grams lighter than stock.
• For better top speed: Stay at stock weight or go 1 gram heavier.

About Dr. Pulley

Dr. Pulley is a Taiwanese performance CVT specialist with decades of experience engineering variator components for scooters and small-displacement motorcycles. Their patented sliding weight technology is widely regarded as the benchmark CVT upgrade, trusted by tuners and everyday riders worldwide for consistent, measurable performance gains.

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