Campagnolo HO 11sp rear derailleurs

Discuss light weight issues concerning road bikes & parts.
bm0p700f
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by bm0p700f

SRAM and campagnolo cassette spacing is not the same so your issue is because of the cassette. The reason why it is not as hesitant on another bike is its another bike. Difference in cable friction will account for the differing shifting quality.

I had an SRAM cassette in a bike with 2014 SR RS and it was hesitant in shifting. Put a Campagnolo chorus cassette in there and it shifted perfectly. Been there done that but I did not blame campagnolo for my cassette choice.

Put a campag cassette on your bike neeb and set it up from scratch (lubricate the cables why your at it) and it will work fine. A bianchi with super record was serviced over the weekend. the shifting on that is not hesitant. Neither is on my athena equipped bike I ride on saturday once I straightened out the hanger.

neeb
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Joined: Tue Jan 27, 2009 8:19 pm

by neeb

Turns out that the underlying problem in this particular case was a stiff upper pivot on my rear mech, but the SRAM cassette was a little more sensitive to this than a Campagnolo one had been.

There was a problem with the upper pivot (perhaps due to wear) whereby torquing the mech onto the hanger with even moderate force caused significant friction that acted against the pivot spring. The suboptimal operation of the upper piviot was enough to throw out the balance of the derailleur and the shifting. The Campagnolo cassette could just about deal with that (although shifting wasn't very good), but the SRAM one was a little more sensitive, doubtless for the reasons you mention, bm0p700f.

I've now fitted a new mech (which happens to be an HO model) and shifting is fine, even with the SRAM cassette. I'll see how it goes..

by Weenie


neeb
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by neeb

Just to set the record straight ('scuse the pun), I wasn't personally blaming Campagnolo for my poor shifting, but once you start talking about this sort of stuff other people jump in.. ;-)

Have now edited the original post to make that clear.

AJS914
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Joined: Tue Jan 28, 2014 6:52 pm

by AJS914

Why was the upper pivot stiff?

This reminds me about those o-rings inside the upper pivot. If you put the wrong oil on them they can shrink or degrade and then add some sloppiness to the upper pivot.

neeb
Posts: 545
Joined: Tue Jan 27, 2009 8:19 pm

by neeb

AJS914 wrote:
Sat Mar 09, 2019 8:15 pm
Why was the upper pivot stiff?

This reminds me about those o-rings inside the upper pivot. If you put the wrong oil on them they can shrink or degrade and then add some sloppiness to the upper pivot.
I wish I knew, because I'm wondering what I can do now with the old rear mech. There are actually two (unrelated) issues with the top pivot assembly. Firstly the torx fixing bolt on the inner side is stripped (don't ask - it doesn't really matter of course because you'd normally use the front one), and secondly there is this issue with the joint siezing up if the mech is torqued onto the hanger with anything vaguely approaching the recommended torque. Someone suggested it was because I'd taken the mech on and off quite a lot and worn something down, meaning that when the bolt is torqued up now it is able to compress the joint and/or spring.

I basically need a new RD-SR006 and RD-SR109, plus the tool and/or knowledge to undo that complicated-looking circlip... But these parts are "service centre only" and I'm assuming that the cost of out-of-warranty repair wouldn't be worth the 2nd hand value of the mech.

Contemplating a nice wall display with some other old campy mechs I have lying around.. :D

neeb
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Joined: Tue Jan 27, 2009 8:19 pm

by neeb

Incidentally, at first glance the old mech and the HO version look identical apart from the updated jockey wheels, but if you look closely from the rear just above the topmost limit screw you can see that the moulding there is a little different - the HO version has a smaller indent:

Image

AJS914
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by AJS914

It's weird that the joint tightens up. You'd think that the circlip on the bolt would bottom out against derailleur hanger when tight.

bm0p700f
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by bm0p700f

Why do you take your rd off alot.

The issue with using SRAM cassettes with campag is the shifting becomes hesitant more quickly with chain wear. If you get long chain life then fine, for me the shifting is poor right within a 1000km (and is only acceptable when new) making a light Sram red cassette unusable.

neeb
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Joined: Tue Jan 27, 2009 8:19 pm

by neeb

bm0p700f wrote:
Sun Mar 10, 2019 1:40 pm
Why do you take your rd off alot.
Well, depends how you define "a lot" - this particular one has been on and off quite a few times as it was on a frame that was crashed, then moved to a new frame, then taken off when I upgraded that frame to EPS, then put back again when I decided I wanted the EPS on a different bike.. Plus it's been on and off for travelling once or twice.

I'm wondering if the problem may have been something to do with having used the inner rather than outer torx socket on the fixing bolt for attaching and removing sometimes. And sometimes I've used both at the same time when removing the RD to equilibriate the forces. It's difficult to see how the whole joint is fitted together from the exploded diagram.. I assume that the inner and outer torx sockets are on the same bolt? Just occurred to me this morning that maybe these sockets tighten against each other, but it's difficult to tell without disassembly, especially with a rounded inner socket..
bm0p700f wrote:
Sun Mar 10, 2019 1:40 pm
The issue with using SRAM cassettes with campag is the shifting becomes hesitant more quickly with chain wear. If you get long chain life then fine, for me the shifting is poor right within a 1000km (and is only acceptable when new) making a light Sram red cassette unusable.
I can only try.. :D My guess is that it's one of several factors influencing optimal shifting and it might be fine if I make sure all the other ones are OK. I can save the best part of 100g with the SRAM cassette setup and that's not to be sneezed at. Compatibility issues aside, the SRAM cassette is a great design for weight saving. Going to fit the maximum smoothness cables just to provide a little more potential wiggle room...

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