bike locked up...where to start?

"Broke" the bike tonight... will start tearing it down tomorrow but wanted to see if anyone has any pointers on where to start, and/or tips and tricks to make the next few days of my life a little easier.



I am not sure if the transmission is locked up or the engine, but no need to get ahead of myself.



Was going downhill about 20-25mph, bike quit and rear tire locked up. All very sudden, no warning. Kickstarter moves a little, but not sure if this is just "taking up play" in the mechanism, or how it even works really. Seems locked up pretty solid so could not start bike.



Had the flywheel off on Sunday night, so I started by laying the bike over on its side and removing left side case. Nothing visibly amiss. Starter gears all turn, but crank will only turn approx. 15degrees. Removed cam cover, nothing visibly amiss. Same 15degrees of rotation as the crank. Removed cam chain tensioner, managed to jump teeth on chain by turning crank. This leads me to believe that piston/crank are moving freely.



Managed to get the bike shifted into neutral at some point, but after that it would no longer shift at all. This makes me think transmission is culprit. Bike rolls around fine in neutral.



Any thoughts? Where would you start if you found yourself in the same position? (Aside from trucking the bike home for the second time in a week)



Let me know if you have questions for clarification, these might not be all the details just throwing the info out to get some expertise