I have a 15 year old Campagnolo Racing-T rear derailleur which shares the RD-RE017 and RD-RE008 springs with many of Campagnolo's other derailleurs through the 10 speed era. While replacing my chain I noticed that the cage now rotates to take up slack in slow motion and the B-tension screw doesn't seem to have much effect.
There seem to be a couple of holes the B-tension spring can go into on the B-tension screw mounting plate, which one is correct?
Do they wear out or break? I've replaced lots of right shifter G-springs, a couple of right thumb lever return springs, and one brake return spring over the last 15 years.