Derailleur Pulleys: Old Atala
I'm restoring [actually, more like rescuing] an old Atala Grand Prix. . .no great value or hot performance. . .mostly for Chuckles-and-Grins and an excuse to listen to NPR.
Issue: The derailleur pulley teeth are worn to nubbins. It's got '70s era Campy low-end derailleurs.
Question 1: How do I determine which off-the-shelf pulley to replace it with?
Question 1a. Is it just the number of teeth that makes the choice for me?
Question 1b. Do I need to be concerned with the size of the hole in the center?
The simplest might be to take the pulleys out and take them to a bike shop. Thread two different wires through the pulleys to mark them and to make sure that you don't lose any pieces if there are any to lose. The teeth determine the circumference and, thus, pulley diameter. In my memory, third party replacement pulleys came with cylinders to fit different axles. Thus, there must be some axle variations between different manufacturers. The replacement pulleys can be quite expensive. Check whether it might not be worth getting a whole new derailleur. Old stock might come cheap on sale or on Ebay.
Originally Posted by Coyote!