Originally Posted by
Kontact
I have seen literally hundreds of Shimano DA and Ultegra RDs on well ridden but cared for road bikes with standard gearing where the B spring is so worn it will allow the upper pulley to rest against the 26t cog with the screw all the way in, despite the fact that the initial installation would only require a few turns to clear.
That coil spring is preloaded, which means that it is well into its elastic range. So I would assume that certain shifts pull the spring briefly past the elastic limit, causing them to deform with time.
That may not have anything to do with the OPs bike, and he has the ability to adjust A tension so it doesn't matter. I just don't think saying that these springs can't be worn is counterproductive to diagnosis.
FBinNY My apologies for not reading your post more carefully.
Thanks for your reply, thats exactly what happened to an old 105 rear derailleur, I experienced that, and have to repair it by myself by drilling a little hole 2mm apart from the original, was enough to get the proper tension again, and have the derailleur working perfect.
Because of that previous experience, is why I think that this campy derailleur has the same problem.