Indexing issue - What to try next?

mattrixdesign2

I am having some issues with my indexing, something I normally get right first time, or at least after 5mins of tweaking.

The bikes was running full 105 triple, it was indexing OK, but the chain, cassette, chainset was wearing and I wanted to change it any way (I wanted CX gering, rather than a triple road setup).

So its now the original 10speed 105 shifters (in very good condition), original 105 rear mech, new cassette (11-28), new chainset (CX50), new chain (Ultegra), used 105 front mech.

The cables outer and inner, were new about 2-3 months ago, seem in good condition.

Front mech is running perfectly.

I am able to get the indexing right, say going from small to big, but then in the reverse I have an issue indexing big to small (as if the mech isn’t pulling right?) – Could be cable inner outer? Could be cable routing? Could be mech – all were working fine previously. I can get the indexing right doing big to small, but loose it going from small to big- ARGGGHH!

The mech and hanger seem good and true.

Despite thinking the inner and outer were fine, I am going to redo it, and try to reduce friction in the process. One area of concern is the bend of the cable coming out from the shifter, and taking the inner curve, of the front part of the handle bars, this is quite tight and it may be benefit from going from the other exit of the shifter, and taking the out curve at the back of the bars? It won’t be as sharp at the bend?

Is this the best place to start, i.e. new inner / outer and reroute? Should I try some “decent” low friction type combination.

All cable ends were prepped and should be good and flat.

Any other thoughts, hopefully not missing the obvious!

arlowood

Sounds like a cable snagging/routing issue.

The RD spring is set to default to the smallest sprocket so when you are changing from small to big, your STI lever is pushing against the resistance/tension of the spring. When you reverse the process to change from big to small, you are relying on the RD spring tension to pull the chain across to the next smallest sprocket.

If the cable is not free in any way due to fraying or tight bends in the cable run, then the up-shift (big to small) could be compromised.

As you indicate that the cables are relatively new and appear in good condition, I would try the re-routing to the back of the bars as a first shot. Also check inside the STI to make sure there is no fraying where the cable is seated.

mattrixdesign2

Exactly my thoughts, so strip them out, new cables (inner/outer) and reroute.

If I re-route the way mentioned how do you route the cable, so it runs on the o/s of the bars, do I follow the outside of the curve then go under the bars near where I grip them (my palm of my hand)?

Ben6899

mattrixdesign2 wrote:

Exactly my thoughts, so strip them out, new cables (inner/outer) and reroute.

If I re-route the way mentioned how do you route the cable, so it runs on the o/s of the bars, do I follow the outside of the curve then go under the bars near where I grip them (my palm of my hand)?

Keep the cable along the back of the bars until it dives down to the cable stop. Keep that curve as large as possible, for as long as possible.

silverpigeon

Have you remembered the 1mm spacer and have you put the chain on the right way round? Both are mistakes I've made in the past.

mattrixdesign2

1mm spacer, you mean on the cassette? Done that before, not this time. Chain is the correct way around.

I bought new gear cable and housing. Stripped the old stuff out, no gunk, no rust, no kinks. Ran the new cable inner and outer. Decided to follow the exact line as before (I.e. outer along the front of the bars above the brakes) as I prefer it that way. Lengthened the last bit of outer to get a nice straight entry to the barrel adjuster. Dissapointed to find the same problem! Meh!

Re ran the again this time with the lesser bend along the back/inside of the bars, voila, much better! Although not sure if its 100% or not, its certainly better. I may be expecting too much perfection, will have to get the summer bike out for comparison

When I bought the previous bike used (where the parts were taken from) I recall the gears being routed this way, I had never had it this way before. When I moved the parts over I recabled them to the front, but that did seem to work until recently.

Just to add to the confusion! The casette is a bigger range (28t) with wider spacing than previous but the mech should take it? Also on turning the chain backwards, the chain just seem to skip/jump a bit, like it has stiff links?! Is this normal? Also played with the angle adjuster, originally tried to get the mech close as possible to the sprockets, since moved it further away as it seemed to have helped. I know I have confused things with all these varying factors but its driving me potty. Going to see how the am commute goes.

The reroute seems to suggest the mech doesnt like the friction, not sure if anything else is making things worse.

Old_Timer

One thing I notice is that you are now trying to sort out several problems at once, you could be adding to the problem(s) with the front mechs if you have made changes to the rear or the chain/cassette, also. Can you reset to the same configuration as when you had just the front mech issues? Sort that one out, then go after the cassette and chain on the rear, would be my course of action. If you did all of this already, or if I misunderstood what you have come to, apologies sir.

One other thought, how clean and smooth is the shifter action at the levers? You might need to flush out the assembly well, so that nothing is hanging up or binding inside there. I had some issues on the front mech of a SRAM Rival double a few months ago that turned out to be the mechanism needing to be cleared out and lubricated to allow things to move smoothly. Just a thought, also. Best of luck on sorting out you problems, triples are one set up that can baffle me into a very frustrating state.

Moonbiker

chain on the right way round

Never realized this are you sure its important?

Seems its only important fro Shimano chains..?

mattrixdesign2

Old_Timer wrote:

One thing I notice is that you are now trying to sort out several problems at once, you could be adding to the problem(s) with the front mechs if you have made changes to the rear or the chain/cassette, also. Can you reset to the same configuration as when you had just the front mech issues? Sort that one out, then go after the cassette and chain on the rear, would be my course of action. If you did all of this already, or if I misunderstood what you have come to, apologies sir.

One other thought, how clean and smooth is the shifter action at the levers? You might need to flush out the assembly well, so that nothing is hanging up or binding inside there. I had some issues on the front mech of a SRAM Rival double a few months ago that turned out to be the mechanism needing to be cleared out and lubricated to allow things to move smoothly. Just a thought, also. Best of luck on sorting out you problems, triples are one set up that can baffle me into a very frustrating state.

No issue with the front mech. Just to clarify, I have gone from a triple 105 setup to a double (CX) 105 setup - with new chainset, casette, chain and used double from derailleur. The front is perfect. Shifters are smooth. Cabling redone and its feels lighter to shift, but there is still an indexing issue.

The key things that have changed is the wider ranging cassette with bigger jumps (28t, I expect the short cage much can take this!?), the new chainset and new chain (measured big ring to big ring + 2 links). It runs nice and smooth, apparently backwards peddling and chain jumps are quite normal.

The cassette seems true and fixed firm with spacer.

My suspicion is the mech, its angle or spring not playing ball or limited to its capacity.... its a hunch as I am not a mechanic but happy to have a go.

veronese68

mattrixdesign2 wrote:

The mech and hanger seem good and true.

Have you checked or do they just look true? I thought mine was alright, but when I checked after trying everything else the hanger wasn't perfectly straight. Sorted that and problem solved. If you're not sure, get something like this.

Phil_D

Have you considered taking it to be looked at by somebody who knows what he is doing?

keef66

Sounds like a bent hanger to me. Can be very hard to spot, even if you take the thing off and lay it on a flat surface. Quick and easy for LBS to check or invest in a tool yourself.

Alternatively I'd have said check for cable fraying inside the shifter, but as you've fitted new ones, twice, that seems unlikely

mattrixdesign2

Pretty sure its not the hanger, but I may have to get it checked.

Phil D - should I bring it to you, after all you are a big tool. Did you sort Tuesday out?

Phil_D

mattrixdesign2 wrote:

Pretty sure its not the hanger, but I may have to get it checked.

Phil D - should I bring it to you, after all you are a big tool. Did you sort Tuesday out?

Almost.

You can borrow my hammer any time.

Old_Timer

Alright, I did misunderstand your question, apologies. I'd suggest what several of the others have, cleaning everything up well, and routing the cables carefully, or replacing them entirely. I purchased a Jagwire Road complete set recently and I was disappointed in the product. I had poor results in the shifting and indexing, switched back to the SRAM inner cabling and thoroughly cleaned the old SRAM housings, the indexing was easily done then, and shifting is spot on.

I was amazed how cruddy the shifter/brake mechs can get over time. Cleaning mine out thoroughly made a big difference in how smooth the shifting was, and in getting the indexing correct. Hope that yours get sorted out.

BTW, I used some You Tube videos to make sure that I was doing the SRAM Double Tap indexing correctly.

mattrixdesign2

All inners and outers replaced. By keeping the routing it made no difference. So then I did a slight re route, where by the cable exited the shifter, but went along the outside of the bars (vs the inside), thus give a longer more gradual curve, and it worked much better (still not perfect), shifting is really light now.

I am now running a CX setup, so that's Cassette 11/28, Chainset 36/46, with the old but clean 105 short cage mech. Doing some calculations the Short Cage mech is fine (Max low sprocket 30, Max front diff 16, Total capacity 34 - so it all fits in with limitations).

I am convinced the hanger/mech is not bent.

When I push the mech manually its seems to move and then stay in its new position (give or take half a CM) , like a spring is not strong enough, compared to my road bike (same size 105) which is more resistant to my finger pushing it and then it returns back to position it was. So I wonder if they current mech had lost its return spring-y-ness , but want to cross check there is no cable resistance any where, so will try again with no cable attached.

Its worth noting that the rear mech was working on a triple setup previously, should a short cage mech be used for this purpose? Has it been put under strain, it wasn't my setup, bought used.

So next step, try swapping mechs - which is a ball ache as it requires breaking and re-joining chains. I could have a look at rerouting the cable around the head tube (current exits right hand shifter/bar and goes to right hand down tube), I didn't think to do this the other day, it may mean a lesser strain from the handle bars to the down tube.

keef66

My first road bike was a 105 triple built from scratch by Epic Cycles, and that came with the longer cage rear mech. So I'd say it is possible a short cage mech may have suffered in that situation. But logically that would have more to do with chain capacity / tension spring than the sideways movement of the parallelogram and it's return spring.

Your description makes it sound like the mech is struggling though. Did the mech come off the bike for a proper clean and lube of all the pivot points? Be interested to hear what it's like with no chain and no cable attached.

(My long cage mech is currently marinading in oil and waiting for new jockey wheels)

Edited to add: You can swap mechs without breaking chains if you take the jockey wheels out. Need to drop the chain off the inner chainring and sit it on the BB to remove tension. (Also handy if you remember which is the guide and which the tension pulley)

Still a bit of a faff. Easier still to join your chains with KMC Missing Links...

mattrixdesign2

It was removed cleaned, lightly oiled and replaced.

I bought I a used TriCross Oct'13, it was pristine, along with a full replacement and like new 105 groupo (triple chainset, mechs, shifters etc). My guess at the time was the the old kit was removed (Tiagra) and replaced, even the shifters still had protective tape as if they were weeks old. It ran well, no real shifting issues (hated the triple, PITA to trim all the time).

Then I bought a proper CX frame, and I migrated the lot over, so all the 105 kit inc Triple, again worked OK, still hated the triple! Recently decided I need to make the gearing more CX friendly, hence ditched the chainset, cassette, chain. Since then I have had the issue.

So I wonder if the mech has been strained/stretched, to the point where the return spring is sloppy? It still looks pristine.

ben@31

Indexing issue - What to try next?

Di2

arlowood

mattrixdesign2 wrote:

So I wonder if the mech has been strained/stretched, to the point where the return spring is sloppy? It still looks pristine.

If a you say the previous owner was running a triple with a short cage rear mech then, as already suggested, your mech has probably been under a bit of strain coping with the range of chain tensions needed for a triple front crank. Also if the previous owner was prone to running big/big or small/small combinations then this would simply exacerbate the situation.

My answer would be - ditch the mech and buy a new or nearly new mech. Cheap enough for a 105 short cage - £23 from Ribble

http://www.ribblecycles.co.uk/sp/road-t ... tAodfUcAcA

I'm pretty sure you've wasted more than £23 worth of your time with all the messing about you've done to date.

I know it's frustrating and you want to nail the culprit yourself but my advice is change the mech.

mattrixdesign2

Just lost a rather large post, I think I have sussed it, not rear mech... but QR adapter on through bolt style axel giving lateral movement to the wheel! Something I missed staring at the cassette that was fitted fine.