@Ford832, I think I said the same thing
(re: "Yes a lot of that has to do with things like porting, exhaust, piston and head shape"). But my point was (and maybe my meanderings lead us astray) that the hit is designed into the bike for whatever the use. Since a 2t is so finicky (pipe, timing, flywheel, port shape, weather, terrain etc), a street engine would be designed for very little hit and a wide range of power whereas an MX engine would be produced to provide peak power in a very limited range and those riders that could harness when it was on the pipe were heroes (i.e. Hannah, Jonny O, even Bubba!). Another example was the old Can-Am range. The '75 Can-Am TNT made more power than most any other 250. It was like riding an Open class bike as it had gobs of power all through the range. The MX version however was an Expert Only bike. It made a bit more power but it hit so hard that you had to have a name like Jones, Tripes or Ellis to use it. Ok, that's a bit of an exaggeration but it wasn't your 'average riders' bike. Of course, that had to do with the rotary disc intake as the engines are the same but it serves my analogy.
As for the whole injection timing issue, and I must preface this as I am not a mechanical or electrical engineer, I don't think that is the issue. Maybe 15 years ago, but not today. Nor is processing power in the ECU (although electrical power may be an issue in packaging). F1 engines turn at 19,000 RPM and that is limited by a common ECU (they used to turn more but were limited for longevity by the rules in the cost cutting initiative). Yes, they are multi-cylinder 4$ engines but the principal is the same: Inject x amount of fuel at y time (with y being a product of rpm and other inputs).