I really don't think Harley would do this. You would need very heavy pistons for this to be necessary, and it might make this area weak. Why would you need to take away material opposite the counter-weight of the flywheel????? Now, we'll have to have Wiley check these - and he'll probably have to drill more holes in the counterweight itself to compensate. These wheels will look like Swiss cheese - and if they hold oil when they're spinning - that ain't really ideal either. The less holes the better I think. Unless you could drill the holes in the ends of the wheels so the oil flies out? What a mess.