Odd RD problem
11-03-08 | 02:07 PM
#1
Thread Starter
Ho-Jahm
Joined: Nov 2006
Posts: 4,228
Likes: 0
From: Manchester, NH
Odd RD problem
I just finished installing a pair of 09 campy "ultra shift" levers on my bike, and am trying to figure out an odd problem with the RD. It wasn't doing this with the old shifters.
I can shift from small cog to biggest cog perfectly, but upshifting from the largest cog to the smallest isn't working properly. On the 13-26 cassette, I can shift from the 26 to the 23 fine, but the next click on the shifter has no effect. Continuing to shift down works until a cog is eventually skipped, generally the 15 or 16T. If I move the RD by hand, it will shift to the correct cog. If I play with the cable tension to get this to stop happening, the cable is way too loose and won't shift correctly in the other direction.
I've got the limit screws in perfectly and the B tension set so the pulley is close to the biggest cog but not close to touching. It's an 07 veloce medium cage on a campy triple set up.
Is my RD spring worn out? It's almost as if it doesn't have enough spring tension to shift by it's self. About a year ago I ran over a stick which flipped up into my spokes and ripped off the RD. A mechanic replaced the hanger bolt and spring with some old campy spares he had laying around. Is his quick fix finally crapping out?
I can shift from small cog to biggest cog perfectly, but upshifting from the largest cog to the smallest isn't working properly. On the 13-26 cassette, I can shift from the 26 to the 23 fine, but the next click on the shifter has no effect. Continuing to shift down works until a cog is eventually skipped, generally the 15 or 16T. If I move the RD by hand, it will shift to the correct cog. If I play with the cable tension to get this to stop happening, the cable is way too loose and won't shift correctly in the other direction.
I've got the limit screws in perfectly and the B tension set so the pulley is close to the biggest cog but not close to touching. It's an 07 veloce medium cage on a campy triple set up.
Is my RD spring worn out? It's almost as if it doesn't have enough spring tension to shift by it's self. About a year ago I ran over a stick which flipped up into my spokes and ripped off the RD. A mechanic replaced the hanger bolt and spring with some old campy spares he had laying around. Is his quick fix finally crapping out?
11-03-08 | 04:10 PM
#2
Senior Member
Joined: Mar 2008
Posts: 2,646
Likes: 2
From: Salinas , Ca.
Bikes: Bike Nashbar AL-1 ,Raligh M50 , Schwinn Traveler , and others
it could be any of the following, dirt in the housing ,which mean replacing the cable and housing, the rear dérailleur's hanger is bent and need replacing (if it the replacing type) or re-iniine with the right tool at your lbs.or as you said the spring finally crapped out again needs replacing.
11-03-08 | 04:14 PM
#3
Senior Member
Joined: Mar 2007
Posts: 2,369
Likes: 0
From: Reston, VA
Bikes: 2003 Giant OCR2
Hmmmm....
So we changed out the *shifters* but not the RD, and now the RD isn't shifting right. Well, it seems odd that the spring would fail at the exact time you switched the shifters. Not buying it.
Let me recap what you did, and let me know if anything's in error.
*Shifting works OK
*Remove derailer cable
*remove shifters
*Re-install new cable.
*Shifting doesn't work
Is that correct? If so, I have an idea:
Whenever I hear about funky indexed shifting that never matches up correctly, coincident with removing/replacing cables, it makes me think that someone might have routed their cable incorrectly at the RD pinch bolt. RDs have a nice feature that lets one mix and match cassettes and shifters that are off by one (ie, 8 and 9-speed) by routing the cable so it pulls a little extra. Problem is, if you accidentally do that on components that are matched, you get too much cable pull per shift, and the indexing doesn't match up.
Check to make sure you routed the cable correctly, you should be able to find an image online (or take a good shot of your RD where the cable attaches and post here).
So we changed out the *shifters* but not the RD, and now the RD isn't shifting right. Well, it seems odd that the spring would fail at the exact time you switched the shifters. Not buying it.
Let me recap what you did, and let me know if anything's in error.
*Shifting works OK
*Remove derailer cable
*remove shifters
*Re-install new cable.
*Shifting doesn't work
Is that correct? If so, I have an idea:
Whenever I hear about funky indexed shifting that never matches up correctly, coincident with removing/replacing cables, it makes me think that someone might have routed their cable incorrectly at the RD pinch bolt. RDs have a nice feature that lets one mix and match cassettes and shifters that are off by one (ie, 8 and 9-speed) by routing the cable so it pulls a little extra. Problem is, if you accidentally do that on components that are matched, you get too much cable pull per shift, and the indexing doesn't match up.
Check to make sure you routed the cable correctly, you should be able to find an image online (or take a good shot of your RD where the cable attaches and post here).
11-03-08 | 05:05 PM
#4
Full Member
Joined: Jun 2007
Posts: 278
Likes: 76
From: Maine
Bikes: '20 Scott Addict RC 30, '13 Trek Soho Deluxe, '91 Greg Lemond Maillot Jaune, Mid '70s Cuevas
It may be that you attached the cable to the wrong side of the fixing bolt, if that is possible. If the cable comes out of the wrong side, it can change the pull ratio slightly, resulting in okay shifting, then double shifts. It happened to me once.
