Campagnolo 10-speed adjustment problem

[Jesper]

Hello

I have a problem getting the rear derailleur to work properly (or even acceptable) on a newly built-up bike with Campagnolo 10-speed.

The setup is: Centaur aluminium levers (old type), Centaur short cage rear derailleur (aluminium model from just before they went to carbon), 13-29 Centaur cassette and Connex 10s8 chain.

The problem is, that I can only get the indexing to work either up or down the cassette. If it works up the cassette (lower gear) then the derailleur moves too far right (seen from the rear) when going back down.

The limit screws are set perfectly and that leaves only cable tension to play with, right? I suspect the problem is cable friction.
When going up the cassette, the derailleur moves a little too far and then settles against the cable tension. It seems like the spring is not strong enough to overcome the friction in the cable and therefore settles a little before it should? If I push the derailleur by hand I can move it a little bit more.

When going down the cassette this problem doesn't arise, since the derailleur only moves in one direction and the spring has momentum on it's side and therefore can stretch the cable fully.

I have tried moving the cable by hand to get a feel for the friction, but I don't know how much is too much.

The cables are original Campagnolo, but maybe 2-3 years old. They seemed very stiff and a little brittle. I can see small cracks where the cables bend.

I hope my explanation makes sense ;-). If the cables are the problem it's extremely annoying since I spent a LOT of time on the bars double-wrapping with inner-tube and padding out the lumps from the cables...

Jesper

[thwart]

I think you're right; you are describing cable friction symptoms.

Short cage RD's and 29 cogs are not always a happy match---but that doesn't sound like the main issue.

[rydesteel]

I use the same setup on my bikes. Is this a new frame? Is the der hanger bent? If the cables weren't new I'd start with fresh cables and housings and see how that works.

[Dave]

The age of cables and housing is not a important as the mileage on them, but if the cables have never been lubed in 2-3 years, that's an issue too.

I'd just install new cables and housing. Shifting to larger cogs should never be a problem, but once that's set correctly, sticking cables prevent proper shifting to smaller cogs.

[keevon]

As others have mentioned it's likely a) cable friction, b) bent derailleur hanger, or c) both.

Two things to try:
1) Keep the cable housing that you have, but replace the rear shift cable with a teflon-coated shift cable. If you're patient, you should be able to fish the cable through the housing without unwrapping your bars.

2) Have your shop check the derailleur hanger alignment. If it's a steel frame with a non-replaceable hanger, they can easily bend it into alignment. If it's an aluminum or carbon frame with a replaceable hanger, buy a Wheels Manufacturing hanger and install it. Be wary of OEM hangers, they're often out of alignment when new.

For what it's worth, I have the same aluminum Centaur levers and derailleur mated with a 13/26 cassette and KMC chain. Rear shifting was a little problematic before I implemented the two changes above, but now everything is fine.

Good luck!

[keevon]

Two other quick things to check:

1) Length of derailleur housing loop at the rear derailleur. If it's too short it could be causing additional cable friction.

2) Cable guide at underside of bottom bracket. Maybe some grit got wedged up in there... put a few drops of lube on it and see if things improve.

[thwart]

2) Cable guide at underside of bottom bracket. Maybe some grit got wedged up in there... put a few drops of lube on it and see if things improve. That's a good tip.

I know for certain that dried (and goopy) Accelerade is not a useful cable lubricant... yes, from personal experience. :crap:

[Jesper]

Thank you for all the replies so far.

I'm just home from the LBS buying af new set of cables. The fact that you have to buy both brake and shifter cables is almost enough to make you hate Campagnolo! Even the guy in the shop said "ouch" when I said what I needed!

To answer some of the suggestions, all parts where unused, I'd just had them lying around for a couple of years. The bike have not been ridden yet - because of this....

It is an aluminium frame with a replaceable hanger, but I'm sure it has something to do with the cable. But maybe I should get the hanger checked anyway.

I routed the shifter cables on the inside of bars (Nitto Noodle), does this make a difference? The housing does make a very sharp bend inside the shifter body, almost making a kink at the end of the ferrule, but that's just the way it is, so it can't normally be a problem.

The housing provided for the loop at the derailleur is definitely on the short side, both on the old and the new set of cables (how much can they possibly save on this!). It looks more like the "short" picture from the Park Tool website:

http://www.parktool.com/images_inc/repair_help/r_housingloops.jpg

The new cables are thinner (4,1 mm) and says Ultra Low Friction on them and have no pre-mounted ferrules. They seem more flexible, so I hope they are better...

[Jesper]

This is also the last time I tape the bars before testing the shifting....

[wasfast]

One quick test for friction issues is to just pull on the rear derailleur cable on the downtube with the bike in the repair stand. You can take out the rear wheel so you don't have to turn the crank. You can feel how much resistance and if the cable is severely restricting the movement. Testing it against another bike is useful also.

On the cable tension setting, I put the chain on the smallest cog, tension the cable at the RD with a pair of pliars (lightly) with my index finger against the RD body while tightening the clamp bolt. Properly tensioned (meaning tight enough) the chain should move up a cog immediately with one click of the shifter. If it doesn't, the tension is too low. Over tensioning usually means the RD won't go to the smallest cog sometimes or not at all and you have instant 9 speed or even 8 if you went nuts.

[Dave]

You're going to be short by two ferrules, most likely. Unless Campy is selling a special version of those cables, they are made to fit 2009 shifters that require no ferrules at the ergo body.

The 4.1mm housing may not fit in some other brand of ferrule, made for 4mm housing, but it's worth a try.

To save money next time, just buy Campy individual cables and 5 feet of Shimano housing, with 6 ferrules.

[thinpin]

Another thing worth checking is the ferrule on the housing at the rear derailleur. I was driven to distraction a few months back with a similar problem. It turned out that the ferrule on the cable going into the stop on the chain-stay was a poor fit. Once I sorted that out the shifting was fine.

[basso1]

All six of my bikes have Campy Record or Chorus. I love the stuff and have used it since 1973, however, it must be adjusted like the manual says to do it. Please read the instructions from Campy.

First, make sure that your chain is the proper length--if not get a new one and make sure that it is Campy. Use the Campy chain tool or have your LBS fit your chain. Anything else is asking for trouble.

Set the tension with the chain on the smallest cog and make the cable very tight. Make sure the der is perfectly vertical to the cog. Run the chain up to the fourth or fifth cog and use the adjustment on the der cable, at the der, to center the chain perfectly on the cog. Do not worry about the 29 cog and short der. It will operate just fine. Good luck.

[Dave]

Do not worry about the 29 cog and short der. It will operate just fine.


This has been hashed over several times. It may work on some bikes, but not all. If the chainstay length is not optimum, then it may over-extend the RD in the big/big. With the chain 1 inch longer, is may hang loose in the small/small. Frames with an optimum chainstay length can gain up to 2T of wrap compared to others.

If you never shift into the big/big combo or course it's no problem.

[basso1]

Yes indeed, the chainstay length is important, however, I cannot imagine using the large chainring and large rear cog. Anyone using a 29 is in desperate need of a 34, 36, chainring!!

[Dave]

It's not intened for anyone to use the 50/29, but you don't want to damage something by accidentally shifting into it with a too-short chain. A 39/29 is a bit lower gear than a 34/25.

I use a 50/34 with an 11-25 (11 speed) so I get about the same low gear, without losing my top gearing. Works well for the mountains.

[Jesper]

Thank you for all your good advice! I think it's time for an update.

I got tired of fiddling with it and went for a ride and it works pretty well on the road. There's still some hesitation sometimes, but it definitely got better with the new cable. Also, I discovered that the bolt holding the replaceable hanger was not torqued down fully - doh!

To answer some of your comments:

Ferrules were included, just not fitted. On second thought, maybe they were intended for the brake cables, but I also have lots of spares.

The suggestion about the chainstay cable stop was a good one. It was a poor fit and I needed to file it, but I did this at the first install.

About the 29t cog. I knew it was not officially sanctioned by Campagnolo, but my research led my to believe that there shouldn't be a problem. Both big-big and small-small works fine in the stand, but of course I never intend to use these combinations. I think the bike has long chainstays - it has fender clearance.

The reason for the 13-29 is, that it gives me almost the same gearing with a 39/53 crank as a 12-27 with a 34/48, which I used previously. This allows me to ride, almost exclusively, in the big ring. I had a Record alloy crank that I really wanted to use and also, more teeth = less wear (a bit silly, but extra bonus ;) ).

I still intend to have the alignment of the derailleur hanger checked.