So instead of shaving the outside of the flywheel, it would (in theory) best to take the material from the center point out to a few mm short of the edge. Or drill holes around it front the center out. But you can't really do that without compromising the integrity of the flywheel right? That's why most lightened flywheels are just skimmed across the face .0xx" and the outer side/ring is left alone?