X4F aluminum layshaft is strategically CNC-machined to minimize rotating weight without compromising strength or integrity. The precision layshaft minimizes runout, eliminating drivetrain vibration and producing a positive balance. The layshaft includes two exchangeable bearings to further reduce drivetrain vibration. The composite belt pulley key solidly to the layshaft, and the completed assembly is installed onto the motor mountââ¬â¢s steel layshaft axle. Machined from premium Swiss 7075 T6 aluminum and black anodized. Fits X4F