Yep. Broken carby slide. It's happened to mine as well at about 5300km.(98 model). First sign of trouble was the revs would not drop back to idle. About 1 km later, I stopped the bike and it would not restart, so I roll started it. talk about an awlfull noise in the top end. Naturally, stopped it immediately. Luckily, there was no piston or bore damage. But I am still $600 out of pocket. A letter is on its way to Yamaha, as this sort of thing should not happen. Any one know if the slide (throttle valve plate) has been redesigned or recalled anywhere?