2 Stroke Reality
I think that the main reason 2 strokes didn't last long on the market is because the OEMS saw that there was way more $$$ in the maintenance of 4- strokes. A 2 stroke bike like a CR 500 can be easily maintained by the owner with very few parts and cost to rebuild the engine, vs a four stroke bike which in 95% cases must be brought back to the dealer for proper repairs. You just cannot compare slapping a new piston & rings vs valves, timing chains, oil pump, and fine adjustments in a four stroke.
Look at what the MX champions like Robbie Maddison & Trigger Gumm, world (record for jump 2008) drive... Two Stroke. Two Stroke.
There is a big gap between what is a really great, reliable, durable, and easily maintained MX two stroke vs a great, reliable, and maintenance dealer-dependent MX 4 stroke. And let's face it, when buying a motocrosser maintenance, time & cost are way up there in the important factors!