I know of 2 EC200's that this has happend to both being 1999's. 1 being mine and the other being my riding buddy. In his case the crank stuffer bolt came out and jammed between the rod and crank while riding. He split the cases and rebuilt the lower end.
On my bike, the same thing happended, I was starting my bike in the shop and it locked up. I was kicking it over I knew right away what had happend. I removed the topend, and bolt the bolt back in. I was able to fish out the bolt, I put loctite on the threads and re-install. I did the same to the rest of the stuffer bolts.