Reconnecting shift cable to front derailleur
#1
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Joined: Dec 2009
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From: Palm Harbor, FL
Bikes: 2018 Specialized Roubaix Sport and Ruby Sport
Reconnecting shift cable to front derailleur
Bought a slightly used bike. FD would not shift onto the smallest ring, and chain was touching FD when middle front/smallish rear. I watched few youtube clips that all followed the same theme. I then made my attempt. While trying to reattach the shifter cable, I can't get it right. Either it is too slack or too stiff to shift onto the large ring. I've taken it off and reinstalled it so many times that the cable is starting to fray. I'm frustrated. Any helpful advice? Shimano Sora, by the way.
Thanks!
Thanks!
#2
Senior Member

Joined: Jan 2004
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Have you looked at the limit screws as well?
You would probably benefit from putting some kind of barrel adjusters between the shifter and derailer. That way the cable adjustment can be tweaked without reattaching the cable.
You would probably benefit from putting some kind of barrel adjusters between the shifter and derailer. That way the cable adjustment can be tweaked without reattaching the cable.
#3
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From: Melbourne, Oz
Bikes: https://weightweenies.starbike.com/forum/viewtopic.php?f=10&t=152015&p=1404231
Front derailleur adjustment is one of the trickiest things to do on a bike... the following assumes the derailleur is mounted in the correct position (inner plate parallel to rings, outer plate clearing big ring by 1-2mm).
First ensure the inner limit screw is properly set, by seeing if the derailleur rubs on the chain when in smallest ring/biggest cog. If there's a gap, turn the screw until it's as small as you can get it without chain rub (remember to allow a mm or so for some flex that will occur when you're on the bike).
Then secure the cable and shift into biggest ring/smallest cog and adjust the outer limit screw in the same way, ensuring the shifter is holding the derailleur against the limit screw.
Back off any barrel adjusters on the cable to a couple of turns from fully loose, pull the cable tight while the derailleur's resting against the inner limit screw, and finally tighten the clamp bolt.
Test shifting and tweak your barrel adjuster to minimise chain rub.
First ensure the inner limit screw is properly set, by seeing if the derailleur rubs on the chain when in smallest ring/biggest cog. If there's a gap, turn the screw until it's as small as you can get it without chain rub (remember to allow a mm or so for some flex that will occur when you're on the bike).
Then secure the cable and shift into biggest ring/smallest cog and adjust the outer limit screw in the same way, ensuring the shifter is holding the derailleur against the limit screw.
Back off any barrel adjusters on the cable to a couple of turns from fully loose, pull the cable tight while the derailleur's resting against the inner limit screw, and finally tighten the clamp bolt.
Test shifting and tweak your barrel adjuster to minimise chain rub.
#4
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Joined: Dec 2009
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From: Palm Harbor, FL
Bikes: 2018 Specialized Roubaix Sport and Ruby Sport
First ensure the inner limit screw is properly set, by seeing if the derailleur rubs on the chain when in smallest ring/biggest cog. If there's a gap, turn the screw until it's as small as you can get it without chain rub (remember to allow a mm or so for some flex that will occur when you're on the bike).
I really appreciate the help. I'll search to see if I can learn more about operation of cables.
#5
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From: Pittsburgh, PA
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
One more thing, is this a Shimano fd? If so, attaching the cable to the fixing bolt the right way is essential. Look at the bolt and you will see a small tab to its left. The cable must route OUTSIDE of this tab and then over the top of the fixing bolt.
If you route the cable between the tab and the bolt, the actuation ratio changes enough that the shifting will not index properly.
If you route the cable between the tab and the bolt, the actuation ratio changes enough that the shifting will not index properly.
#6
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From: The 'Wack, BC, Canada
Bikes: Norco (2), Miyata, Canondale, Soma, Redline
....This is most likely the problem, and I think that it's because I don't understand the mechanics of the cables. I was tightening the barrel until it stopped then loosening two clicks before trying to tighten the clamp. So for your way, backing off the barrel adjuster makes the cable slack, then I pull it by hand and then tighten the bolt? But then I've pulled the slack out of the cable and I'm at a position on the barrel where I can only tighten it and add more tension to a cable already under tension. Is this correct?
#7
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From: Oklahoma
Bikes: Trek 5500, Colnago C-50
Go to www.parktool.com and find the instructions for setting up and adjusting the derailleur. Do all of the steps in proper sequence leaving nothing out.
#10
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From: Melbourne, Oz
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#11
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Joined: Dec 2009
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From: Palm Harbor, FL
Bikes: 2018 Specialized Roubaix Sport and Ruby Sport
If I make the cable shorter, am I making it more slack or more tense?
When I turn the barrel counterclockwise, what am I doing to the tension? What about clockwise turning?
Thank you!
#12
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From: Melbourne, Oz
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Look at your right hand. If you make a thumbs-up shape, the direction you turn any right-hand threaded fastener to go in the direction your thumb points is the way your fingers curl. Hence 'righty-tighty, lefty-loosey' when looking down on the fastener. But don't think in terms of tight and loose here, cause that's confusing. Screw in or unscrew.
So if you screw in an adjuster, it makes the effective housing length shorter, loosening the cable. Unscrewing the fastener lengthens the effective housing length, tightening the cable.
Shortening the adjuster until tight means to screw it in until it stops.
So if you screw in an adjuster, it makes the effective housing length shorter, loosening the cable. Unscrewing the fastener lengthens the effective housing length, tightening the cable.
Shortening the adjuster until tight means to screw it in until it stops.






