Adjustable Hub Flywheel Fits Honda GX340/390, Predator 420, and most 13-16HP Clone engines The ARC Billet Flywheels are CNC machined from 6061 T-6 Aluminum. It weighs 5.40 lbs. The main feature of this design is the steel crankshaft hub that allows for timing changes at 2 degree increments. Designed for use with on-board electric starter. Like all billet flywheels, this flywheel does not have internal magnets for the lighting/charging feature found on some engines. The coils under the flywheel must be removed to install this flywheel.