I am running a wipperman chain on a campy record, 50/34 front, initially 11/23 rear, recently switched to 12/25, have about 1500 miles on it. Initially had a little noise from the rear der in a few of the smaller rear cogs, but since i switched to 12/25 it is getting worse. sounds like clickety clack clickety clack like not quite shifted right, worse going up hill or sprinting, less when spinning or softpedaling, and worse with smaller rear cogs, worse in little ring that big in front. My thought is maybe the chain has stretched a little and is too loose, or maybe a wipperman chain is too wide for my campy? appreciate any ideas or thoughts.
9 ot 10-speed cassette and chain? They should match. The chain length may be too long. Also, did you check the b-screw setting to make sure the upper der pulley isn't touching the cogs?
Just to cover your bases ... is the Wipperman joining link installed the correct way up? (thats if it is the kind with two opposing curved plates) one edge has a shallower curve than the other.... If upside down it can cause chain chatter. Also .. check derailleur hanger alignment ... if you've bumped the derailleur it will only take a couple of mm to throw out gear selection.