You know, I didn't think that last part through. In order to be clean the fuel must be injected after the exhaust port is closed (as the piston passes it), but of course done by the time it fires. Very little time. I'm sure there must be a math head here that could say how long that would be at say 10k RPM, but suffice it to say not much time.
The Evinrude 2t outboards are to be propped to run 5-6k RPM WOT, so about half of what one might expect from a 250 or 500cc bike.
Look what that does for you though. 195 fewer parts than a competative 4t...
And look at the weight difference...
Since often there are a pair of these things hanging off the back, that's 500lbs. savings!
Alas, I'm afraid politics may never allow a return of the 2 stroke, but on the other hand if one is produced that meets current emissions and offers better performance through less weight and much greater simplicity... we can only hope.