One of my friends Klein Quantum frames that is about 5 years old had its derailleur hanger crack during a ride today. He baought it used with like less then 100 miles on it at the beginnning of the summer. He recently put a new ultegra rear derialleur on it.
I am wondering if he could have installed this incoreectly, if it is possible to still get warantee on it, and if the aluminium can be welded to replace the derailleur hanger?
Does anybody have any suggestions on a new frame under 400 or a used frame under 400.