I thought 2-strokes had poor emissions was the injection of lubrication oil into the air fuel mixture. traditional 2-strokes I'm familiar with pull in air into the crank case (which requires lubrication), then uses a portion of the exhaust stroke to compress the fuel/air creating forced induction. By keeping air out of the crank case and providing lubrication delivery outside of the air/fuel mixture, emissions can be significantly improved. The article claims the design allows external lubrication, but it doesn't say how. I'd like to see how the seals are better than apex seals.
The basic crankcase-scavenged two-stroke suffers from both problems. Typical diesel two-strokes use a separate blower for scavenging, so the combustion air inflow never passes through the crankcase and does not come in contact with the lubricating oil, while the fuel is not injected until after the exhaust is closed.
The engine described here can have its shaft and eccentric bearings externally lubricated, but its apex seals, like those of Wankel engines, seem to be in a situation analogous to that of a piston ring. Unlike either of those, however, they are mounted in the stator, not the moving part, and so may be easier to lubricate precisely.
My 1960s cafe racer (years ago!) had oil injection. Some engines do have oil injection and just inject it into the inlet port, but in this engine it was delivered directly to the crank bearings. From there it was flung all over and ultimately burned. Anyway, as the saying goes on the lost continent of Perl: "There's More Than One Way To Do It".
