Put yourself in the Government's shoes. Do you want them to number crunch every facet or the car/bike, and tell you exactly which models that you can and can't drive. A 90% fix that requires no administration is a good solution. BTW, wasn't the 2 stroke loophole was patched in NSW in the early 90s?

I still think that driver education is the best way. Lose it sideways at 120kmh on a racetrack, and your freshly stained underpants will remind you of your car's limits.

I think Charles Darwin got it right. If you drive like a crazy man, you'll be asked to leave the gene pool.