I have never seen a arc flywheel out, this is not to say anything is possible? I have had other things that made the assembly out such as welding on the pulley that attaches to the crank. Yours is off a little over half an ounce? not terrible in my world, the amount of overbalance can vary this much depending on the type of engine, easiest thing is just to balance the complete assembly from flywheel to crank pulley. Just my 2 cents.