Hi people, so you've all heard that this question, but I think I've tried most obvious things and need further help.
So I have Shimano Acera gears on my Boardman. The chain is clean and lubed. As far as I know the derailleur has not had a knock. The high, low and b screws screws are set correctly.
I can't get the barrel adjustment so that the gears change up and down nicely, they either go up nicely or down nicely....not both. If I set it so they go down nice I have the click the shifter to go back up and then push a little more to get the chain to shift up, and sometimes I end up clicking a second time so the process starts again and I'm going for a gear I don't want, it's getting frustrating!!!
The jockey wheels when viewed from the back don't look perfectly aligned with the cassette, they're sort of aiming for the front gears (in gears 1-6 on the back anyway)
I'm giving the adjuster tiny adjustments each time. It just seems to me that there isn't enough movement between each click!?!?
Can anyone help??
Cheers.
I'm a trendy consumer. Just look at my wobbly bog brush using hovercraft full of eels
Indexing gears
Re: Indexing gears
have you tried replacing the gear cable? If it is in the slightest bit draggy the gears won't work properly.
There are lots of other possibilities but that is where I'd suggest that you start.
cheers
There are lots of other possibilities but that is where I'd suggest that you start.
cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
Re: Indexing gears
Many indexing problems can be caused by draggy cables.
Check inners and outers for snagging, fraying, kinks, etc. Check outers are ground flat at cut ends and ferrules are snug against cable stops. Lubricate appropriately. Replace if necessary.
Check inners and outers for snagging, fraying, kinks, etc. Check outers are ground flat at cut ends and ferrules are snug against cable stops. Lubricate appropriately. Replace if necessary.
High on a cocktail of flossy teacakes and marmalade
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karlitfingers
- Posts: 35
- Joined: 11 Nov 2016, 6:41pm
Re: Indexing gears
gaz wrote:Many indexing problems can be caused by draggy cables.
Check inners and outers for snagging, fraying, kinks, etc. Check outers are ground flat atcut ends and ferrules are snug against cable stops. Lubricate appropriately. Replace if necessary.
Thanks Gaz! Good advice, didn't think about this! If I leave the gears after changing they eventually move, maybe the cable is being too slow at moving??
I'm a trendy consumer. Just look at my wobbly bog brush using hovercraft full of eels
Re: Indexing gears
If the cable is draggy, you can adjust the indexing so the gears change ok up the block towards the bigger sprockets.
This is because the cable is being pulled by the gear changer.
When you release the cable to move the gears down the block, you are reliant on the rear mech springs.
Ideally, the rear mech spring and the pull of the changer should balance out. One pulling equally against the other with friction and "tug" being the same.
If the cable is draggy, the equilibrium is upset.
This is because the cable is being pulled by the gear changer.
When you release the cable to move the gears down the block, you are reliant on the rear mech springs.
Ideally, the rear mech spring and the pull of the changer should balance out. One pulling equally against the other with friction and "tug" being the same.
If the cable is draggy, the equilibrium is upset.
Mick F. Cornwall
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old_windbag
- Posts: 1869
- Joined: 19 Feb 2015, 3:55pm
Re: Indexing gears
When I'ved had that situation it has been as suggested cable related. In each case the short section feeding the rear mech which being horizontal on my chainstay picks up lots of water,dust etc over time, migrating into inner. When I had the issue initially years ago I put a tab of masking tape on the down tube bare cable and could observe the movement of the masking tape indicating the difference in cable movement up/down... clearly it should be the same both ways, it wasn't. It doesn't take much friction to oppose the spring return. One direction you provide the pull against the spring, the opposite direction requires the spring in the rear mech to provide the release force.
Sorry but I've just repeated most of above as they were faster typing
.
Sorry but I've just repeated most of above as they were faster typing
.Re: Indexing gears
As the others have said, draggy cables.
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karlitfingers
- Posts: 35
- Joined: 11 Nov 2016, 6:41pm
Re: Indexing gears
Nice one people! I'll attempt to check this, I've not taken cables out or checked this before so I feel a bit of research coming on!
I'm a trendy consumer. Just look at my wobbly bog brush using hovercraft full of eels
I'm a trendy consumer. Just look at my wobbly bog brush using hovercraft full of eels
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karlitfingers
- Posts: 35
- Joined: 11 Nov 2016, 6:41pm
Re: Indexing gears
On a quick check the cable is definitely rusted as it goes into the final rear mech section, and under the bottom bracket was a rusty looking, I've given it a spray with some penetrating lube for now until I can take it apart and clean properly. The cable did look like it was being pulled back enough but maybe a fraction slower than it should.
I'm a trendy consumer. Just look at my wobbly bog brush using hovercraft full of eels
I'm a trendy consumer. Just look at my wobbly bog brush using hovercraft full of eels
Re: Indexing gears
If the cable stops are slotted put it in bottom gear then move the lever to top without turning the cranks, so the chain stays on the big sprocket. There should be sufficient slack to remove the outer from the cable stop, pull the inner through the slot and then slide the outer along, allowing you to add further lube to the section that will be inside the outer when you slide it back.
Should improve any temporary fix, as it has rusted you should fit new cables.
Should improve any temporary fix, as it has rusted you should fit new cables.
High on a cocktail of flossy teacakes and marmalade
Re: Indexing gears
^^^
Excellent idea.
Sounds to me, that it's a good maintenance regime as a preventative.
Excellent idea.
Sounds to me, that it's a good maintenance regime as a preventative.
Mick F. Cornwall
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karlitfingers
- Posts: 35
- Joined: 11 Nov 2016, 6:41pm
Re: Indexing gears
Ok people, so I sprayed underneath the bottom bracket and got som spray lube in the spot where I suspect water got it....gears have worked perfectly since, no need to change anything. I think I was lucky that the water hadn't got it too far!
I'm a trendy consumer. Just look at my wobbly bog brush using hovercraft full of eels
I'm a trendy consumer. Just look at my wobbly bog brush using hovercraft full of eels
Re: Indexing gears - I have the same problem
Hi all,
I am hijacking the thread because I have the same problem although the cause may be different. My bike has fallen over countless times, sod's law usually to the right. No matter how carefully I place it, as soon as I step away the wind whips up and throws it to the ground!
The bike is Whyte Dorset now 3.5 years old with Shimano Tiagra 10 speed cassette. The gears changed perfectly when it was brand new but it all went downhill from there. Even after the first service, the LBS adjusted it and it was better for a few months but then lost the performance again. So it didn't got back to LBS for a service after that...
Earlier this year I realised the service was really overdue when the chain came apart. After that I replaced the chainrings, cassette, chain and inner gear cable with new stuff as close as possible to the original spec, or better if I couldn't find an exact replacement, so I presume there shouldn't be any compatability issues. The same FSA 50/34 chainrings, Shimano ultegra 10 speed chain (don't know what the original was), Shimano 105 11-28 10 speed cassette (the original was a Tiagra with a slightly wider range but they were out of stock).
The problem is as the OP described, I can't get it to change both up and down cleanly. I have currently settled for having the cable slack enough that it shifts up, and I push the lever beyond the index point to shift down. The gear cable seems to be moving OK, its a new cable and I lubed it before I installed it. I haven't replaced the outer cable because it goes inside the frame and its a continuous piece from the shifter to where it ends underneath the bottom bracket (why you would make the inner cable exit there at the dirtiest point I don't know but that another issue) so it seems there should be very little opportunity for water ingress and corrosion inside it. Replacing it would be cheap but potentially a pain to do.
I bought a hanger alignment gauge and checked the hanger which is now pretty much spot on but it didn't fix the problem. The cable seems to move back and forth OK when I use the shifter so I hope the lever is OK. My suspicion is that the repeated falling over has damaged the rear derailleur although I can't see any damage apart from some superficial scratches. Each of the springs individually feel quite strong but somehow the overall movement seems sluggish and slack and I am not sure it is tensioning the chain sufficiently. I did shorten the chain slightly compared to the original because the cassette is smaller, I don't think it can be shortened any further. The b-screw doesn't seem to do much which ever way I adjust it. Derailleur and all pivot points have been cleaned and lubricated to no avail. It would be easy to replace the derailleur and at about £25 for the same as the current one its probably still cheaper than the LBS labour charge, but I don't want to replace it and find I still have the problem.
Any suggestions please as to the probable source of the problem?
I am hijacking the thread because I have the same problem although the cause may be different. My bike has fallen over countless times, sod's law usually to the right. No matter how carefully I place it, as soon as I step away the wind whips up and throws it to the ground!
The bike is Whyte Dorset now 3.5 years old with Shimano Tiagra 10 speed cassette. The gears changed perfectly when it was brand new but it all went downhill from there. Even after the first service, the LBS adjusted it and it was better for a few months but then lost the performance again. So it didn't got back to LBS for a service after that...
Earlier this year I realised the service was really overdue when the chain came apart. After that I replaced the chainrings, cassette, chain and inner gear cable with new stuff as close as possible to the original spec, or better if I couldn't find an exact replacement, so I presume there shouldn't be any compatability issues. The same FSA 50/34 chainrings, Shimano ultegra 10 speed chain (don't know what the original was), Shimano 105 11-28 10 speed cassette (the original was a Tiagra with a slightly wider range but they were out of stock).
The problem is as the OP described, I can't get it to change both up and down cleanly. I have currently settled for having the cable slack enough that it shifts up, and I push the lever beyond the index point to shift down. The gear cable seems to be moving OK, its a new cable and I lubed it before I installed it. I haven't replaced the outer cable because it goes inside the frame and its a continuous piece from the shifter to where it ends underneath the bottom bracket (why you would make the inner cable exit there at the dirtiest point I don't know but that another issue) so it seems there should be very little opportunity for water ingress and corrosion inside it. Replacing it would be cheap but potentially a pain to do.
I bought a hanger alignment gauge and checked the hanger which is now pretty much spot on but it didn't fix the problem. The cable seems to move back and forth OK when I use the shifter so I hope the lever is OK. My suspicion is that the repeated falling over has damaged the rear derailleur although I can't see any damage apart from some superficial scratches. Each of the springs individually feel quite strong but somehow the overall movement seems sluggish and slack and I am not sure it is tensioning the chain sufficiently. I did shorten the chain slightly compared to the original because the cassette is smaller, I don't think it can be shortened any further. The b-screw doesn't seem to do much which ever way I adjust it. Derailleur and all pivot points have been cleaned and lubricated to no avail. It would be easy to replace the derailleur and at about £25 for the same as the current one its probably still cheaper than the LBS labour charge, but I don't want to replace it and find I still have the problem.
Any suggestions please as to the probable source of the problem?
Re: Indexing gears
Hi Fatbob,
10s shimano road systems are very sensitive to cable condition; arguably they are the most sensitive index system available, since they have the shortest cable pull and a high shift ratio. In tiagra they changed shift ratio between 4600 (washing lines) and 4700 (underbar cable routing). The 4700 shift ratio is more forgiving but the cable routing isn't. If your indexing stayed good for several months after an LBS service then I'd argue that they did a good job. Often the entire cable set requires replacement (including the outers) at similar intervals. Your bike is manifesting all the signs of iffy cables.
The mech may be worn too; the upper jockey pulley should have a small amount of side-to-side float but should not wobble. Nor should the teeth be worn. Better quality shimano mechs have pulleys with better bushings in and they last longer. Often the top pivot wears and this allows the whole mech to flop about to the detriment of shifting.
BTW the hanger alignment specifications allow for one degree 'toe out' and one degree of 'negative camber' ; some bikes shift slightly better with this set in than with the mech 'perfectly aligned'.
I'd suggest that your cables may be
a) lacking in lube (of the right sort) and/or
b) the outer housing may be worn enough to cause trouble and/or
c) the inner cable is starting to deteriorate where it flexes most.
To verify that the cables are not perfect, remove the chain from the rear mech and measure its movement carefully, e.g. by measuring the gap between a spoke and the mech. If the position is different depending on whether it is an upshift or a downshift to get to a certain point, then most likely the cables are bad. If the wrong lube (or worse yet, no lube) has been used then most cables can go bad quite quickly; the wrong lube can gunge everything up or attack the liner in the cable so that it softens and swells.
BTW if you are contemplating replacing a worn rear mech you choices will vary with the shifter fitted. If you have ST4600 then you can use any 9s mech or any 10s road mech (except RD4700) of suitable capacity with those shifters. If you have ST4700 then you can use any road 11s rear mech or RD4700.
cheers
10s shimano road systems are very sensitive to cable condition; arguably they are the most sensitive index system available, since they have the shortest cable pull and a high shift ratio. In tiagra they changed shift ratio between 4600 (washing lines) and 4700 (underbar cable routing). The 4700 shift ratio is more forgiving but the cable routing isn't. If your indexing stayed good for several months after an LBS service then I'd argue that they did a good job. Often the entire cable set requires replacement (including the outers) at similar intervals. Your bike is manifesting all the signs of iffy cables.
The mech may be worn too; the upper jockey pulley should have a small amount of side-to-side float but should not wobble. Nor should the teeth be worn. Better quality shimano mechs have pulleys with better bushings in and they last longer. Often the top pivot wears and this allows the whole mech to flop about to the detriment of shifting.
BTW the hanger alignment specifications allow for one degree 'toe out' and one degree of 'negative camber' ; some bikes shift slightly better with this set in than with the mech 'perfectly aligned'.
I'd suggest that your cables may be
a) lacking in lube (of the right sort) and/or
b) the outer housing may be worn enough to cause trouble and/or
c) the inner cable is starting to deteriorate where it flexes most.
To verify that the cables are not perfect, remove the chain from the rear mech and measure its movement carefully, e.g. by measuring the gap between a spoke and the mech. If the position is different depending on whether it is an upshift or a downshift to get to a certain point, then most likely the cables are bad. If the wrong lube (or worse yet, no lube) has been used then most cables can go bad quite quickly; the wrong lube can gunge everything up or attack the liner in the cable so that it softens and swells.
BTW if you are contemplating replacing a worn rear mech you choices will vary with the shifter fitted. If you have ST4600 then you can use any 9s mech or any 10s road mech (except RD4700) of suitable capacity with those shifters. If you have ST4700 then you can use any road 11s rear mech or RD4700.
cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
Re: Indexing gears
Hi Brucey,
Thanks, that is very useful information. I thought if everything was Shimano 10s then it would be compatible but apparently not. My gear cables are not the under-tape type so I must have the older 4600 model. I presume the change between 4600 and 4700 only affects the matching of shifters and rear mech, not the sprockets? My gears seem to change better on the biggest sprockets and worse in the mid range but that might be because the cable tension is higher on the bigger sprockets? The cassette is 105 5700 so I don't know how that relates to 4600 or 4700 for the shifters but since it came as a unit I presume the spacing between sprockets should be correct for a 10 speed system. Only the few biggest sprockets are actually fixed together, the others are loose, some with spacers between and some maybe having spacers fixed to them already from what I remember. Anyway it seemed to be the right total width to replace the old cassette.
What is the right sort of lube to put on the cables? I think I squirted GT85 into the outers and wiped some on the inner wire.
The "slack" in the rear mech is if you manually rotate it (with the chain on) forward or back around the main pivot where it attaches to the hanger. When you let go it springs back but not very precisely so it could end up further forward or back from where it started. That pivot was very stiff at one point but I took it apart and gave it a good clean and lube and it seems to move OK now. Is there likely to be more than one position for the spring in that pivot so I could have put it back together on the wrong setting?
Thanks, that is very useful information. I thought if everything was Shimano 10s then it would be compatible but apparently not. My gear cables are not the under-tape type so I must have the older 4600 model. I presume the change between 4600 and 4700 only affects the matching of shifters and rear mech, not the sprockets? My gears seem to change better on the biggest sprockets and worse in the mid range but that might be because the cable tension is higher on the bigger sprockets? The cassette is 105 5700 so I don't know how that relates to 4600 or 4700 for the shifters but since it came as a unit I presume the spacing between sprockets should be correct for a 10 speed system. Only the few biggest sprockets are actually fixed together, the others are loose, some with spacers between and some maybe having spacers fixed to them already from what I remember. Anyway it seemed to be the right total width to replace the old cassette.
What is the right sort of lube to put on the cables? I think I squirted GT85 into the outers and wiped some on the inner wire.
The "slack" in the rear mech is if you manually rotate it (with the chain on) forward or back around the main pivot where it attaches to the hanger. When you let go it springs back but not very precisely so it could end up further forward or back from where it started. That pivot was very stiff at one point but I took it apart and gave it a good clean and lube and it seems to move OK now. Is there likely to be more than one position for the spring in that pivot so I could have put it back together on the wrong setting?