Sweet! I hadn't noticed that about the new Shimano derailleur pull.

I'm in the process of trying to set up a bike with "new" Campy shifters (post-2001 but pre-2008), an "old" (1998) Racing T rear derailleur and a Shimano-splined wheel/cassette. I started out with a pair of 9-speed Centaur shifters and, as promised, the indexing seemed to be correct. Unfortunately the indexing gear in the shifters was pretty worn and so I had problems with the shifts being mushy and the indexing tending to slip (the shifter itself would actually go back a gear in some cases).

After pricing replacement indexing gears (not readily available), I decided to buy a complete new Record shift assembly. I now have a right shifter with Record internals and a Centaur brake blade. I set it up last night only to discover that I didn't have a 10-speed chain. The indexing again seemed correct, but the 9-speed chain I had on the bike from the previous experiment seemed to be rubbing the shift ramps from adjacent cogs, leading it to float up and down as the cassette rotated. I picked up a 10-speed chain today and I'm hopeful that this will resolve the issue for good. I really want this set up to work because the 90's Campy rear derailleurs looked so much nicer than anything they've made since.



Meanwhile, I'm also in the planning stages of a bike that I hope will have "new" 10-speed Campy shifters (2014 Centaur), a "new" 10-speed rear derailleur (2003 Chorus long cage), with a 10-speed Shimano-splined cassette. Like you I've read reports that this will "kind of work" without further gymnastics, but I don't want just "kind of working" so I'm planning further gymnastics. My plan is to replace the 10-speed cassette spacers in the Shimano cassette with 9-speed spacers. This should approximate Campy spacing over the part of the cassette that has replaceable spacers. The Shimano cassette only has four replaceable spacers, but the limit screws will fix the innermost and outermost gears in the correct place, leaving me with just four gears that are only approximate, and those should be within 0.2 or 0.4 mm. The catch here is that the 9-speed spacers will make the cassette 0.8mm wider. Happily, I was planning to use the 10-speed cassette on an 11-speed hub, so I have 0.8mm to spare.

If all else fails, I will consider an 11-speed Shimano RD as a backup plan. I could probably sell my used Chorus RD, buy a new 105 RD-5800 and have enough left over for a pretty nice steak dinner.