Watch and Learn: Kawasaki Rider Is Fast but Can't Corner [Video]
The good side of this thing is that many of them are at least wearing protective gear and make it through without sustaining serious injuries and hopefully learning the lesson, even though the hard way.
Watching this video was yet another reason to keep on telling the same thing to the young riders, over and over again: "it's not about speed, but about learning how to corner. And once you're feeling comfortable leaning into the turns, maybe you can try going fast."
Sorry, but this fellow needs to learn how to lean and corner before he's back on that Ninja, at least for his own good.