Wow, that was a bad one. My accident resulted in a punctured lung too. Oddly enough though, it wasn't from riding but from an accidental gunshot which left me paralyzed from the chest down. Worst accident I ever had was while riding an old Kawasaki F7 175. Wasn't a good handling machine to begin with but this one had a bent frame, and worn out suspension that was more like pogo sticks. Front wheel got deflected by a rock at about 45 mph, and I broke my wrist. I guess I was pretty lucky on dirtbikes, looking back.
Anyhow, I look forward to seeing some fast videos on the mighty KX, see it flex it's muscle a bit, but be careful. My friend I mentioned in my previous post who had the '84 Honda CR 500 up-geared for the desert too. I didn't up-gear my IT 465 because of the gear spacing. Unlike it's YZ 465 counterpart, there was a big jump from third to fourth and I feared it would cause too much of a drop in RPMs which would hurt my acceleration. Had it had the YZ's close ratio gearbox, I'd not have hesitated to up-gear it, as it easily had the power to pull it. I did however, ride my friend's CR 500 many times after the gear up, and I know what those big old 500s can do. They can really bite you if you're not careful. His cornered great, but at high speeds, the headshake was terrifying. I don't think the KX you have, which I believe is in the 450 4stroke frame, should have that problem though, since I know Kawasaki uses the 450 in desert races currently. Even so, be careful. I enjoy the slower vids too. I did a lot of plunking around on that IT. It was very good at that.