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Discussion Starter · #1 ·
Hello all,
I have searched and found nothing to really answer my question.

Ultegra 6700 10spd on Jamis Eclipse (Steel Frame)

I started having a problem tuning the shifting to get alignment across the entire cassette range. If I tune for the higher gears, the lower gears have issues and vice versa. Below is all of the work and things I have checked.

1. Replaced Cables
2. Had rear hanger (steel frame integrated) checked and aligned twice.
3. Checked for any cable binding points
4. Checked B-Tension to find that it never engages so I cannot adjust for it.
5. Based on B-Tension issue, I replaced rear derailleur. Still unable to adjust for B-Tension as it does not engage.
6. Removed all cable tension to ensure my rear housing loop wasn't limiting rear derailleur position and inhibiting b-Tension position.
7. Shortened chain to minimum length.
8. Cleaned and re-lubed shifter internals.

I am starting to think the bike was never adjusted for B-Tension, but regardless, the jockey wheel is not being pulled in close enough to the rear cogs and I suspect this is part of issue. Not sure if it is a frame hanger design or what but the B-Tension is not adjustable.

So if the B-Tension was never correct and the bike shifted fine for 4 years, the only component left to replace is the shifter itself and I'm ready to do that but it's driving me crazy that I cannot adjust derailleur tension position.

Any ideas out there???
 

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What do you think replacing your shifter will achieve? A few questions:

1) Did you replace your cable housings when you replaced your cables? Did you use good quality stainless steel cables, not galvanized cables? Do your cables feel nice and slippery smooth, not rough?

2) What do you mean by can't adjust B-tension? The B-adjust will do nothing more than move the jockey pulley toward and away from your cassette. For optimal shifting, you should adjust it as close as possible when in the largest cog, without actually touching. However, if it is too far, it will not cause the problem you are talking about.

3) You said you had your hanger alignment adjusted twice. I'm wondering if it has now fatigued to the point where it bends out of alignment easily. This would be the 1st place I would look with the problem you describe.
 

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7. Shortened chain to minimum length.
Don't know what this means except that it won't help. Chain should be shortened to the maximum length using the small-small method.
 

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Don't you mean large-large?
Small small will make the chain too short to go to a larger diameter gear.
No, that is not the case. Small-small is the way you do it. Large-large will probably result in over shortening and limit the size of rear cog.
 

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Small small will make the chain too short to go to a larger diameter gear.
This is only true if you are exceeding the capacity of the derailleur. If you are within that capacity, small-small will give you the maximum chain length, which means that you have the most flexibility. It also gives lower drivetrain friction, though you could argue whether that is significant.
 

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I'm almost sorry I started the chain sizing discussion again!

I note that OP has not returned to his thread, but a couple of other comments.

OP seemed a little obsessed with the B-screw adjustment. IME the B-screw adjustment is only really needed to increase jockey clearance on a "large" cassette and OP does not tell us what cassette is on the bike. RD is likely delivered with the screw backed out, so it's adjustment is only in one direction. In any case it's not the cause of shifting issues.

Again, we were not told of the age or usage of the shifter, but maybe it is the problem They don't last forever.
 

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I'm almost sorry I started the chain sizing discussion again!

I note that OP has not returned to his thread, but a couple of other comments.

OP seemed a little obsessed with the B-screw adjustment. IME the B-screw adjustment is only really needed to increase jockey clearance on a "large" cassette and OP does not tell us what cassette is on the bike. RD is likely delivered with the screw backed out, so it's adjustment is only in one direction. In any case it's not the cause of shifting issues.

Again, we were not told of the age or usage of the shifter, but maybe it is the problem They don't last forever.
So with what you just said, not questioning you just asking in general. The B-screw is the only adjustment that gives me issues as to it making a difference in shifting performance.

On my Shimano Ultegra 10spd stuff I run a 53/39 on the front and a 11/28 on the rear. In the big/big combo in regards to B-screw adjustment even with the B-screw all the way in I don't ever see the jockey wheel get close enough to have contact. Now on my MTB with XTR and 11/40 on the rear yes I can see contact and have to adjust the B-screw to keep it from happening, on the road I don't see it happening.

So basically if you can screw the B-screw all the way in with no touching then should you leave it that way, or does it need to be screwed out for some minimal tension at least?
 

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I can only repeat that I have never noted differences in shifting performance based on the amount of clearance of the upper jockey wheel.

And for the OP and you I note that Shimano's instructions only refer to adjusting the B screw when in the small ring.

Mount the chain on the smallest chainring
and the largest sprocket, and turn the crank
arm backward. Then turn the B-tension
adjustment screw to adjust the guide pulley
as close to the sprocket as possible but not
so close that it touches. Next, set the chain
to the smallest sprocket and repeat the
above to make sure that the pulley does not
touch the sprocket.
 

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So with what you just said, not questioning you just asking in general. The B-screw is the only adjustment that gives me issues as to it making a difference in shifting performance.

On my Shimano Ultegra 10spd stuff I run a 53/39 on the front and a 11/28 on the rear. In the big/big combo in regards to B-screw adjustment even with the B-screw all the way in I don't ever see the jockey wheel get close enough to have contact. Now on my MTB with XTR and 11/40 on the rear yes I can see contact and have to adjust the B-screw to keep it from happening, on the road I don't see it happening.

So basically if you can screw the B-screw all the way in with no touching then should you leave it that way, or does it need to be screwed out for some minimal tension at least?
I think you may have it backwards. Screwing the B-screw IN (clockwise) pulls the jockey wheel AWAY from the cog and vice-versa. If you want it to be closer, you need to back the screw out (counter-clockwise). Back the screw out until the two are close, but not touching while you are shifted into the largest cog.

Where you need to adjust this all depends on a few things like the size of your largest cog, the geometry of your derailleur and the length of your cage.
 

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I will check it tonight when I get home, though even in small/big I still can screw the B-screw out all the way and still not touch so I wasn't sure if at least some tension was suggested or not.
 

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I will check it tonight when I get home, though even in small/big I still can screw the B-screw out all the way and still not touch so I wasn't sure if at least some tension was suggested or not.
The system will have tension as long as there is clearance. The B screw is really just to increase clearance if needed. The system will have least clearance in the small ring which is why the B screw is set there, to set minimum clearance. Putting the chain into the big ring automatically increases clearance. Which is another reason to say that clearance is nothing to do with shifting accuracy.

It's not clear from our missing OP whether or not he was trying to adjust when on the small ring. Barking up the wrong tree anyway.
 

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The system will have least clearance in the small ring which is why the B screw is set there, to set minimum clearance. Putting the chain into the big ring automatically increases clearance.
Are you sure about this? Unless I am missing something, if there will be any contact between a cog and the jockey wheel, it will be in the large cogs.
 

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Are you sure about this? Unless I am missing something, if there will be any contact between a cog and the jockey wheel, it will be in the large cogs.
Yes. And in the small chainring. Which is why Shimano's instructions start there.
 

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Yes. And in the small chainring. Which is why Shimano's instructions start there.
Ooops, sorry! Brain fart! You wrote ring and my brain read cog (smacking side of head).
 

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Discussion Starter · #19 · (Edited)
Sorry I have not returned guys but I was travelling out of country for work. To address some questions here.

1. When I say I cannot adjust B-Tension, I mean that the screw is all the way out and the jockey wheel is still miles from the cassette when on the largest cog. Meaning, there is no way to get it closer. I replaced the derailleur and increased the length of the housing loop to make sure nothing is stopping it from rotating up. This has stumped a few mechanics who simply cannot understand why the jockey wheel is so far away when there is no B-Tension applied.

2. The cables and housings are both new and Dura Ace models so they are high quality. I feel no binding in cables anywhere.

3. The chain was shortened to what I feel is the minimum working length to insure enough chain tension is present for derailleur to operate correctly. This made no difference.

4. What I have observed with the poor indexing is that it usually only happens during a release shift down towards smaller cogs so I wonder if the sifter mechanism is not fully releasing everytime. I have sprayed solvent, compressed air, and Teflon lube back in to the shifter mechanism but no change. This is just confusing because I can "tune" it out of one end of the cassette and it shows up in the other.

5. If the derailleur hanger is fatigued and not holding true, then I guess I have to chuck the frame because it is steel and the hanger is integrated. I don't believe this is the case. The first guy who attempted to straighten it only worked in horizontal axis, and not vertical as he rushed. The second guy who straightened it spent considerable time and I have a little more trust in him since he is a friend/shop owner/trained mechanic. His shop just happens to be 60 miles away so I tried a local first.

6. New Chain

7. Gearing 34/50, Cassette 11-28
 

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the jockey wheel is still miles from the cassette when on the largest cog.
But are you in the small chainring?

How about a side view of small ring - small cog, and small ring - biggest cog.

Probably a worn shifter anyway, but it would be good to see exactly what you are talking about.
 
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