Campag veloce rear derailleur problems

chris74

Hi
I have a 10 speed campagnolo veloce grouper and am having shifting problems .it only seems to occur downshifting from 3rd largest cog to 4th largest cog when I am on the large chainwheel. My cassette is 13-26 and chainwheel 50-34.
I also have a medium cage deraileur fitted. I have change all the cables recently as well

jimbohorizontal

Bent hanger?

chris74

Possible. But changing works fine in the small chainwheel

thecycleclinic

You dont guess with shifting problems. Check everything.

It could be chain length, chain wear or cassette wear.........

chris74

Hi I replaced the cassette last week and installed a new campag chain at the same time. The gap between the upper roller and chain is 20mm with 54 outer links. When I tried it with 55 links the chain touched top roller

chris74

Following on is there a way to check if rear der pivots are sticking?

dabber

Am I missing something here? What exactly doesn't work? Does it not change sprockets at all, skip, not index properly or what?

chris74

It doesn't index properly when downshifting from largest cogs in large chainwheel as though the rd is sticking.
It works fine on the small chainwheel.

pblakeney

B-Screw?
Not sure if that is the right description.

veronese68

New chain has less sideways play than the old one, using big/big is trying to pull the chain out of line so it's not happy with an imperfect set up. Little ring gives a better chain line so it's not as fussy. The worn chain was more tolerant of bad chain line and would put less sideways pressure on the back end.
Something is just a little bit out, check everything as said above. Could still be hanger alignment, adjustment or anything.