Rear derailleur shifting issue....
Hi
I've just finished my recent build and I'm having problems with the rear derailleur. I've built all my previous bikes and do all my own maintenance but am stumped with this one.
The shifters and derailleur are 105 5700 10 speed. I did the build as per the instructions and previous builds but had the following problem - the chain won't move from the smallest cog up to the second or even the third withou my having to put about a dozen turns on the barrel adjuster. Once the first 3 are indexed then I can't shift down from any gear without taking off around the same amount of turns off the adjuster.
I've rechecked allignment with the derailleur and the smallest gear lots of times and even played around with this setting but to no avail. The cable isn't slack by any means when I clamp I to the derailleur and I have taken up the slackness and even tried pulling it taught with pliers but that didn't help.
All the cable routing is external and not catching. If I unclamp the cable I can feel the cable pull and release as I play with the shifter so the shifter seems to be working fine.
The cassette is brand new as is the chain. The cassette is sat correctly on the hub.
So effectively, I can set it up to shift up through the gears but will only drop once I've shifted down 3 or so gears.
I thought maybe it was the derailleur so I took my Ultegra off my TT bike and put it on and exactly the same thing - connect the cable and I can shift up twice and the chain satays on the 12t ring.
Am I missing something blatantly obvious?
The bike is a Kinesis 4s frame
105 5700 group set with a new chain and 12-27 cassette (new). All cables and housing is new but I have checked all the housing and definitely not snagging anywhere.
Thank you if you read all of this...hope you can help.
S
I've just finished my recent build and I'm having problems with the rear derailleur. I've built all my previous bikes and do all my own maintenance but am stumped with this one.
The shifters and derailleur are 105 5700 10 speed. I did the build as per the instructions and previous builds but had the following problem - the chain won't move from the smallest cog up to the second or even the third withou my having to put about a dozen turns on the barrel adjuster. Once the first 3 are indexed then I can't shift down from any gear without taking off around the same amount of turns off the adjuster.
I've rechecked allignment with the derailleur and the smallest gear lots of times and even played around with this setting but to no avail. The cable isn't slack by any means when I clamp I to the derailleur and I have taken up the slackness and even tried pulling it taught with pliers but that didn't help.
All the cable routing is external and not catching. If I unclamp the cable I can feel the cable pull and release as I play with the shifter so the shifter seems to be working fine.
The cassette is brand new as is the chain. The cassette is sat correctly on the hub.
So effectively, I can set it up to shift up through the gears but will only drop once I've shifted down 3 or so gears.
I thought maybe it was the derailleur so I took my Ultegra off my TT bike and put it on and exactly the same thing - connect the cable and I can shift up twice and the chain satays on the 12t ring.
Am I missing something blatantly obvious?
The bike is a Kinesis 4s frame
105 5700 group set with a new chain and 12-27 cassette (new). All cables and housing is new but I have checked all the housing and definitely not snagging anywhere.
Thank you if you read all of this...hope you can help.
S
0
Comments
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Pictures?"Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
Parktools :?:SheldonBrown0 -
It's almost certainly the cable tension - my tarmac suffers from this and I think it's where it passes under the bottom bracket. If you've got access to the bare cable above and below then you can check the relative tension before and after.
One way to prove this would be to connect the shifter directly to the rear mech going through just one short bit of housing - if it works then your problem is along the cable length. If not then it's in the shifter (as you've already swapped mechs)0 -
Definately a gear cable and not a brake cable? The cable housing is for gears not brakes is more what I am meaning.0
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It's most definitely not a brake cable!
The last thing I have yet to change is the poition of the cable guide under the BB. It's interesting that you may mention that. The guide has two crew holes and by moving it across I would be making the cable run a path of less resistance.
As for pics, I'll see what I can do but have always struggled to post them on here.
Thanks for you help.0 -
If you say all is aligned at the rear mech correctly for the smallest cog and the cable has tension but not over tension and you are definitely at the correct click point at the shifter end, you have:
faulty shifter
cable mis route somewhere -- too sharp an angle
why not try with the cable not tied in to the handlebars, see if shifting works as it should?0 -
Assuming the gear cable isn't internally routed, put the rear DR in the smallest cog. ensure the Shifters are also set for the smallest DR. adjust the cable barrel until the cable is just loose. Now pull on the cable and it should easily move the rear DR up a cog or 2. If it does, then it's getting snagged farther back ie towards the handlebars, if it doesn't then it's being snagged towards the DR. This can be done at the chainstays and the downtube. Hopefully this might help pinpoint where the issue is.There's warp speed - then there's Storck Speed0
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Any chance you have not pushed the cable outer right into the gear shifter aperture and then taped it all up thinking it was ok?seanoconn - gruagach craic!0
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Thoroughly check that your housings are all fully seated.
Check that the cable nipple is correctly seated in the shifter.
Make sure your derailleur hanger isn't loose.- - - - - - - - - -
On Strava.{/url}0 -
Right....finally got it sorted. It appears it was the length of the cable housing into the rear mech. I didn't think it was any shorter than I'd normally fit but clearly it was.
Thanks for all the comments.0
