With the impressive results folks are having with the newer twin-ring Ryobi 31cc vs the older single-ring versions, plus the fact that most of the "pro-grade" industrial engines (e.g. Kioritz, Echo, Zenoah, etc.) all have dual ring pistons, wouldn't it be a fairly simple hop-up to machine an extra groove on a single-ring piston to accept a second ring? Afterall, larger automotive engines typically have several rings - some for compression and some for oil control.

It shouldn't be all that difficult if you have access to a lathe, should it? Has anybody tried this?