Originally Posted by
Bianchigirll
Normally the rear axle is centered over the mounting bolt for the RD. I don't recall the exact dimensions but I believe there was something specific for Super Record era and since Chorus is still based on that is seems to make sense. If you max cog isn't over 27T you don't really need to use the B position.
As others have mentioned Synchro was finicky and once I learned it was never going to shift like Suntour I learned to over shift and use the clicks more as a guide rather than simply relying on clicking. I eventually went to Retrofriction.
I am not under any illusion that Syncro is ever going to index without issues; originally I had the Athena derailleur with the Syncro shifters so I knew what to expect. I just noticed that because the Chorus is a drop parallelogram, unlike most Campy derailleurs through C-Record (except Ralley), so I reasoned a longer housing loop would work better than the shorter SS coil. I had hoped that Syncro might work better with the only slant parallelogram derailleur Campy released to that date with a Syncro insert for it; unfortunately, it doesn't seem to work any better but I'm going to play with it some more. This was just an experiment anyway. The Syncro doesn't fit the rest of the bike which is now almost all SR, I just wanted to see if I could make it work.