Dr. Pulley Variator Kit for 125cc – 150cc GY6 Scooters, ATVs, and Go KartsSPECIFICATIONS: Includes SlidersDoes Not Included Roller WeightsNumber of Splines: 19Drive Face Outer Diameter (A): 114mmBoss Inner Diameter (C): 15mmBoss Outer Diameter (B): 24mmRamp Plate Inner Diameter (D): 15mm Fan Inner Diameter Peak to Peak (H): 14mmFan Inner Diameter Valley to Valley (G): 15mmThis performance Dr. Pulley Variator (front clutch assembly) is specifically made for the GY6 150cc engine. Therefore, this clutch only works for the GT 250 or Standard 250 or any other 250s on the market that are Forward/Neutral/Reverse OR Forward/Reverse.Specially coated ramp plates create less friction on the rollers or sliders, allowing them to adapt more rapidly to changing driving conditions and resulting in less wear.The steep angle ramp plates in the Dr. Pulley variators allow for faster and smoother engagement at all speeds, and allow lighter weighted sliders to fully extend to make the most of your CVT syst