rear sprocket is BROKEN

[TQuentin1]

OK, that makes more sense. The sprocket shearing without an accident was a very strange situation. Glad you are back to it!!

TQ

 

[ironmark]

Here are some pics . It also looks like the plating is coming off . Maybe the pulley is suppose to look this way , I just heard the clunking noise & seen the crack & assumed that it was the pulley that was broke . The pulley has more of a shine by the seam so I assume the belt was riding on that side .