Bicycle Mechanics - 10 speed Ergopower levers and 9 speed Dura-Ace derailleur/cassette: relationship woes

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.
atelierf.lab
09-13-10, 10:05 AM
I am trying to mate a pair of 10 speed Campagnolo Ergopower levers to a 9 speed Shimano cassette via a 9 speed Dura-Ace derailleur. I would love to use the alternate cable routing that has the cable running around the outside of the hooked washer (http://www.hubbubcustom.com/articles_ergopower.html) but I'm having trouble dialing it all in. Seems to work fine once or twice up and down the cassette, but then the shifting gets erratic again. Is that just tension changing as a bowed shifter cable finds a new equilibrium, and will settle down once the cable resigns itself to the required bend, or is the whole technique just a kludge that doesn't work that well?
Is there another way, outside of something like a Shiftmate, to get that same effect? I cannibalized a bigger hooked washer from a dead derailleur that makes the wrapping of the cable less finicky (the Dura-Ace washer is a bit dainty) but if there was a different technique I would love to try it.
HillRider
09-13-10, 10:50 AM
Why not just get the Shiftmate and be done with it? I've used Campy 10-speed Ergo brifters with a Shimano 9-speed cassette and Shimano rear derailleur for thousands of miles with a Shiftmate and the shifting has always been spot on all the way across the cassette. Do it right.
DaveSSS
09-13-10, 12:16 PM
I agree that the cable routing to lengthen the lever arm is a bit crude and wouldn't produce the same effect for all users.
One way to tell if the lever arm is close to the correct length is to take the chain off, start with the upper pulley aligned with the smallest cog, then shift to the largest cog. Swing the upper pulley so it's close to the large cog, to see if the total travel is too great or too little.
The problem is the Campy shifters pull an average of 2.8mm and the Shimano RD only needs 2.5mm. 11 speed shifters are much closer, with an average pull of 2.6mm.
One other suggestion is to concentrate on the shifts to larger cogs first. Those shifts require cable pull. If those all work, then worry about the shifts to smaller cogs. A cable friction issue can make those shifts perform poorly, even with the proper cable tension. Reducing the cable tension is not the way to fix a cable friction problem.
atelierf.lab
09-13-10, 12:17 PM
You are probably right. I was hoping to avoid introducing another part into the drive train (partly for aesthetic reasons, which is a pretty weak reason) but I am not sure a weird kinked cable is a better way to go. Does your shiftmate sit nice and square against the derailleur? I tried to install one once and it didn't like sitting flush against the nipple that leads into the derailleur. Perhaps I need to adjust the housing length some more.
atelierf.lab
09-13-10, 12:22 PM
Dave, that is also some excellent advice. If only there was a way to take the chain permanently out of the drive train, imagine how clean and smooth it would be! Thanks for the explanation. I think I understand the problem a bit better now.
I am going to start from scratch (the cables and housings could certainly use replacing) and then think about a Shiftmate. It does seem to have its fans out there.
Powered by vBulletin® Version 4.1.12 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.