Campagnolo veloce derailleur not shifting down

RobinB2

I have a Campagnolo Veloce (circa 2005) rear derailleur on my commuting bike. This has provided sterling service for many years but is now not shifting consistently onto the two smallest gears on the cassette. Usually when this has happened on other bikes it has been because of sticking cable issues. However the cable is running freely as far as I can tell

I have cleaned the derailleur and put some lube on the pivots but still no joy. If I manually move the derailleur backwards and forwards several times it seems to free up for a while but then the problem returns. Any clues or tips on how I might resolve this before I either strip it down or (more likely!) buy a new unit

Any feedback much appreciated

bontie

Could possibly be that the cable tension is too high? So on downshift does not "release" enough?
Or the springs are abit tired?

Monty Dog

Sounds like the pivots / parallelogram spring might be gunked-up. Suggest you remove the mech and dunk it in a bucket of cleaner and get to it with a toothbrush, particularly getting inside the parts. More drastic action is to remove the pivot pins.

RobinB2

Thanks for the feedback - cable tension seems to be fine - I suspect it is an issue with the pivots or sprint tension. Is there any way to increase the sprint tension?

Monty Dog

You need to drive out the parallelogram pivot pins to remove the spring and then simply bend the spring leg with some pliers before refitting

desweller

Monty Dog wrote:

Sounds like the pivots / parallelogram spring might be gunked-up. Suggest you remove the mech and dunk it in a bucket of cleaner and get to it with a toothbrush, particularly getting inside the parts. More drastic action is to remove the pivot pins.

Warm diesel is good for this. Submerge and work the derailleur through its full range of motion several times. Then drain, dry and oil. Make sure you do it outside though; when the fuel is warm it will vaporise quite readily.

rolf_f

Another approach is to use an ultrasonic cleaner - I did this this week to a rear mech with exactly the same problem. Comes up like new in five minutes or so and cleans all the parts you can't get at. Ultrasonic cleaners can be had for £20-£30 from the likes of Maplins and are really good for dealing with grubby bike components and all sorts!

cycleclinic

On modern veloce mech the pivot pin appear to screw in, not sure on the older ones though.

rolf_f

thecycleclinic wrote:

On modern veloce mech the pivot pin appear to screw in, not sure on the older ones though.

Torx on the current ones - slotted head bolts on the older (that's about 2008 vintage Record, 2010 Centaur (near enough the same thing) vs 2013 Veloce.