|Chorus rear derailleur woes||RichC|
Mar 20, 2002 7:35 AM
|Just completing the installation of a Chrorus 10 speed group on my new frame and am having severe difficulty setting up the shifting on the rear derailleur.
Have followed the instructions, set up the limit screw with perfect alignment on the smallest sprocket, shifted up to the fourth from last sprocket and adjusted cable tension to give good shifts on the smallest five or six sprockets. The problem occurs when I now change to the small chain ring and attempt to shift through the larger sprockets. The chain now wants to overshift to the next largest sprocket. So I adjust cable tension to give good shifting over the five or six largest sprockets. Now when I shift back up to the large chain ring and try to get good shifting on the smaller sprockets shifting is screwed.
In short I cannot get the derailleur to shift well over the whole cassette.
I have removed the cassette and made sure all the sprockets and spacers are seated correctly, and that the cassette is correctly torqued on the hub. Even tried a different rear wheel and cassette with exactly the same problem.
Have never had a problem setting up Chorus before and now am thinking that maybe the derailleur hanger or derailleur cage may be bent causing the problems.
Any thoughts greatly appreciated.
Mar 20, 2002 7:48 AM
|These may sound obvious questions, but to give us a bit more to go on:-
1) You are using 10 sp Campy shifters - if not, what?
2) You are sure you have the correct (Campy) spacing there - what casette are you using - a wheels man. one or a Campy?
Mar 20, 2002 8:04 AM
|I am using a full Campy Chorus 10 speed group, it is a Chorus 12-25 cassette on Mavic Ksyrium wheels with ED10 hubs. The other wheels I tried were Chorus hubs with a different Chorus 12-25 cassette.|
Mar 20, 2002 8:40 AM
|In that case (and assuming that there has been no mix-ups like wrong chain), then I think you are right to suspect your allignment at the derail somewhere, or some drag/fricton in the cables somewhere.
Try taking the cable off the derail, pulling it for tension, and shifting up and down to feel for tightness.
Failing that - does the shift over the "working" cogs feel even, or is it getting "clicky" towards the end of the "working range"?
Mar 20, 2002 9:04 AM
|The shift does feel even over the working range, although rather strangely when shifting from large to smaller sprockets on the large chain ring the shifting is poor, but when shifting from smaller to larger sprockets it is good.
From my limited technical knowledge, this would back up your theory of some friction in the cables (i.e. shifts ok when tension being increased in the cable, shifts poorly when tension is being decreased in the cable i.e. friction).
Maybe worth trying new cables and housings.
Mar 20, 2002 9:09 AM
|Sounds that way. To possibly save a little cash/time, try the same experiment holding the cable out of the shifters at the bar (i.e. between the housing end and the lever) - this should tell you if it's a cable or a shifter problem.
Could be a "Campy wears in, Shimano wear out" issue, at the risk of starting a major conflagration...
|This NEVER happens with 5, 6, 7 or 8-speed...||retro|
Mar 20, 2002 8:06 AM
|Jeez, I hate to be a retrogrouch...but are we all SURE 10-speed is an improvement for the average rider over stuff you had to adjust maybe once a year?|
|This NEVER happens with 5, 6, 7 or 8-speed...||Brit Racer|
Mar 20, 2002 8:19 AM
|I've had Chorus 10 on my bike for almost a year and a half now. Been riding through 2 British winters (and a British summer!) and not had to adjust it yet...
I would suspect that the problem is being caused by drag in the cables somewhere. Especially at new, adjustment should be really easy - try running an inner through all the outer sections and see if any are tight.
|re: Chorus rear derailleur woes||templecat|
Mar 20, 2002 10:36 AM
|Try this: Loosen the nut that holds the cable, tighten down the adjusting nut, tighten the nut that holds the cable, do the hi-low adjustment and away you go!
Worked for me, good luck.
|re: Chorus rear derailleur woes||jimPz|
Mar 20, 2002 4:21 PM
|Something else to check, Campy likes to grease their cable casing internally, I've had the grease cause the extra friction (grease was too thick). Pull the cable in and out a few times & wipe off some of the grease.
|Check cable ends||Kerry|
Mar 20, 2002 5:00 PM
|Along with the cable friction issue, make sure that you don't have any burrs or excess cable lining at the ends of the cables. This can cause a lot of friction and therefore the problem you're having. My own experience with 9 speed is that you can just slap it on and go, adjustment need is minimal. You've definitely got something wrong here.|
Mar 20, 2002 9:25 PM
|You might have the cable on the wrong side of the der locking screw.
Look at the pic in the pamphlet and make sure you get the cable locked down in the right location.
|re: Chorus rear derailleur woes||mackgoo|
Mar 21, 2002 8:10 PM
|The cable lead sounds good. Another thing if that doesn't pan out is how is your rear hub. Once I had a very loose rear hub and it gave me shifting fits like this.|| |