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I am having trouble adjusting the shifting on my Campagnolo Super Record rear derailleur. I have set the high and low limit.

I think the main problem now is that the jockey wheels are too far away from the cassette (around 1cm when it should be 5mm). I tried to do this with the H-Screw.

However, when I turn the H-Screw... Absolutely nothing happens. Nothing moves, I turned the screw until it cam out, put it back in, not a single change.

So my question is: How is the H-Screw supposed to work? Is there a spring or something that I may be missing?

In this photo, the H-Screw is fully extended: Screw Extended

In this photo, the H-Screw is fully inserted: Screw inserted

Here is the back view: enter image description here

Side view: enter image description here

Is it possible that my chain is too short, or that the derailleur hangar is bent? I can't think of any other explaination.

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    can you put a photo of this H-screw? and of the derailleur from some different angles, including the back of the derailleur hanger – Swifty Jul 4 at 19:29
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    In the third picture the derailer is clearly tilting in towards the wheel. Odds are the hanger is slightly bent. – Daniel R Hicks Jul 4 at 20:18
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    @Carel in the case of Campagnolo, where they say H-screw it is not the high limit screw, but the screw to adjust the guide pulley up and down. Those Italians! campagnolo.com/media/files/… – Swifty Jul 4 at 20:57
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    @Hannes I'm afraid I'm reaching the limit of my Campagnolo-wisdom. I would be checking that the derailleur fits on the hanger tab properly and also trying this adjustment in the low gear (large cog) as that is the gap that wants to be 5-7 mm according to the manual. The gap to the smallest cog may or may not be affected. If you are in the big chainring then the chain is probably not too short, but I can't tell which chainring. – Swifty Jul 4 at 21:04
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    Sorry I don't mean anything by that, shouldn't have put it in. The manual says to adjust the gap with screw H when the derailleur is in the lowest gear, but in the photos the derailleur is in the highest gear. So see if that makes any difference, being in the low gear. There is also the screw L but manual isn't very detailed on how to use that. – Swifty Jul 4 at 21:30
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The H-screw aka b-tension aka angle adjustment is meant to be adjusted in the lowest gear position for any rear derailleur where the guide pulley is offset from the cage pivot, which is most of them, including this. The manufacturer recommended distance will always be for that position.

For conventional road derailleurs like this, that 5mm number really means just short of the chain rumbling in the low gear. Two ways of saying the same thing.

All that said, it's not likely the H adjustment is your problem. It's a subtle adjustment and won't make or break shifting in most cases, the exceptions being if it's way out for no reason or on a derailleur with excess pivot slop from wear.

It's likely you're dealing with one of the common rear derailleur maladies Iike hanger alignment, cable friction, incorrect tension, etc. Hanger misalignment is a likely candidate from your pictures. Eleven speed has little tolerance for it.

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  • Thank you. I will oder a new derailleur hangar and see whether that fixes things, and if not, take it to the LBS. – Hannes Hertach Jul 5 at 8:07
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You don't say specifically what your set up problems are but when training mechanics we recommend starting with the fundamentals and then working upwards, not skipping steps or assuming that things are correct, that may later prove not to be. That potentially saves you from a lot of lost time trying to get something to work where you have an undetected, fundamental, problem - that might be preventing correct function.

I'd suggest that you check all of the basics by reading / applying the information found in the relevant Campagnolo technical manual, freely available at www.campagnolo.com under Support>Documentation>Technical Manuals. Use the date filter to look at the 2012 Technical Manual as that is the one that applies to this gear system and subsequent, up to 2014, version Super Record. This group is exceedingly reliable, provided it's assembled correctly - but like all modern groups from all three major manufacturers, it does not tolerate poor set-up well.

Things that are often overlooked include checking that the levers that you have match the rear derailleur - 2015 and later levers don't work correctly with 2009-2014 derailleurs - that the cassette is properly torqued on the cassette body (40nm) - since this can affect sprocket-to-sprocket spacing - and that the cassette body is properly retained on the hub (the fixing nut is left-hand threaded to help it stay tight under thread precession - but even so, it's worth making sure it's locked), that the rear wheel is fully in the dropouts (best done with the bike on the ground), that the rear hanger is fully tightened to the frame and as commented above, is correctly aligned.

Set the high-gear limit screw without the gear cable attached - that way, you know that the only limited to derailleur movement in that direction is the limit screw, not a pre-load on the gear cable.

Then for the other adjustments, as Nathan says, H Screw adjustment is set when you are on the small chainring and the biggest sprocket.

11s systems are generally more vulnerable to incorrect sprocket to upper jockey spacing than say, 10, 9 or 8s (in descending order of sensitivity) and become more so, the greater the levels of wear and tear in each component, including the rear derailleur itself. Yours is at least 5 years old, so even if you have a new chain and cassette and new jockey wheels, there will be wear in the derailleur pivots, at the very least (unless it's NoS, of course).

When in that small chainring, big sprocket situation, as noted, you should have a 5-7mm gap between the tops of the jockey wheel teeth on the upper jockey, and the tops of the teeth on the biggest sprocket. It can be problematic to run the RD too close to the sprockets - there has to be enough clearance for the chain to climb "over" the teeth of the biggest sprocket, as well as for the chain to run without the "rumble" that Nathan comments on - which is why the 5-7mm figure, rather than "as close as possible" is given.

This spacing is not repeated on the big chainring (as you appear to be in the images) and / or in other sprockets (in the images, the chain is around the wrong sprocket) but by adjusting the balance between the upper and lower springs in the rear derailleur (which is what the H Screw does), when in that "easiest" gear, if the system is otherwise correctly assembled and set up (assuming all compatible components), the spacing on all the other sprockets will be correct.

Beware using 11-29 on these earlier 11s systems - in terms of maximum ranges, they work correctly on 12-29 or 11-27 but 11-29 slightly exceeds the largest-to-smallest sprocket size capacity of the rear derailleur and that occasionally gives shifting issues. This problem was fixed in 11s systems from 2015 onwards.

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  • Thanks for your very detailed answer. The person I bought this bike off of mentioned changing the shift levers because the old ones broke. The levers are actually Chorus levers, not Record/Super Record. How can I tell from which year they are, and whether they are causing the problem? Thanks – Hannes Hertach Jul 6 at 12:10

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