Originally Posted by
Grand Bois
No, and I worked at a Peugeot/Raleigh shop. They do get sloppy after many miles, though.
It's funny that if you research Delrin, you'll find that one of its main uses today is pulleys.
Maybe "new" Delrin works better because of UV inhibitors (which they might not even have used on the old Simplex derailleurs) and plasticizers??