Originally Posted by
kingston
Let me get this straight. You have a broken part on your bike and you're asking if you should replace it?
Cracked derailleur pulleys are common, at least for Campagnolo Nuovo Record and similar derailleurs.
So, I think it is a valid question of what will happen if one continues to use them.
Unfortunately, my limited testing did not go well, at least if the crack is pretty bad.