I looked at a 350x that was seized, put it in 6th gear and pulled it backward and it turned over. Tried kicking it and it would do all most a full revolution and lock up again. On a different engine I was rebuilding when the crank and counter balancer was installed in the left side cover and rotated it did the same thing rotate almost a full revolution then locked, it would rotate the other way and lock, never did buy the bike that would lock up or figure out why the other motor locked. Hopefully this isn't your case, and it is just the rings stuck.