Last fall I picked up an 05 YZ125 that looked like it had never been ridden. It still had the original tires, chain, sprockets, and brakes. I pulled the top end apart and it indeed all looked like new. I threw in a new piston just to be safe since I had it apart. I rode it for about 7 hours and then had the tip of a spark plug break off, destroying the piston, cylinder, and head. I put all new parts on and have since ridden it a bit more. I was planning on updating the shift stopper over the winter since reading about all of the potential issues, but it looks like I'm a little late. With 10.5 hours on my hour meter (less than 4 since my last cotastrophe), the bike began to shift hard and was hard to find neutral. Sure enough, the shift stopper has come apart. I have yet to get any metal out in the oil though. I tried filling the tranny up with kerosene just to see if I could get a single ball from the bearing to flush out, but nothing. Now it is time to split the cases and see how things look inside. This bike just seems to be bad luck for me.