Another Shimano lockring question - Ultegra 11 spd

[aoxomoxoa]

Please can someone advise whether there should be a spacer between the lockring and the first sprocket (11 tooth) on an Ultegra 11 spd cassette (11-32T). I don't currently have said spacer, but this means the serrated surface on the lockring is engaging with the serrated surface on the first sprocket, which seems very graunchy to use a technical expression.

The Shimano parts list document implies there should be one http://www.sjscycles.com/Drawings/Shima ... ch_Doc.pdf but I don't recall there being one when I put the new cassette on.

Thanks.

[Cugel]

It's something of a guess but I believe that the serrations are there to help keep the lock ring fully engaged - they prevent the ring coming loose until you apply significant pressure with the removal tool.

Some lock rings come with the very thin metal washer, which is too thin to be regarded as a spacer so is perhaps intended to distort between the serrations so that they still work but without the small peaks of those serrations getting worn off by cassette removal and replacement. ......

Anyroadup, the lock rings seem to work without the metal washer, even if the ring is removed and replaced a couple of times or so.

As I mentioned, something of a guess. Brucey will enlighten us with the pukka gen, any minute now.


Cugel

[Brucey]

yup there should be a thin metal shim

https://www.sjscycles.co.uk/cassettes/shimano-deore-xt-csm737-lockring-spacer-10z-0400/

normally it is held captive on the lockring.

With or without it fitted the tightening operation is a bit (to a lot) lumpy.

cheers

[aoxomoxoa]

Many thanks, I shall acquire said item forthwith

[NATURAL ANKLING]

Hi,
Whats its purpose Brucey?

[Brucey]

I think it lowers the torque on the lockring required to get the thing tight enough. However you can normally do without it once the lockring has been on and off a few times (which is just as well since the shim gets torn up) at which point the serrations are a bit worn and the lockring tightens easily enough anyway.

There are about 100 teeth in the serration and the screw thread is ~1mm pitch which means that each 'click' results in ~10 microns (less than half a thou') more compression. However the serrations are about 250 microns high which means that with metal spacers in the cassette, the lockring may never tighten enough unless the metal shim is fitted. Plastic spacers are more elastic which allows the lockring to tighten more easily. However with plastic spacers in the cassette they can 'relax' over time which results in a reduced clamping force and can often allow the lockring to go up about another 1/4 turn once the thing has been installed for a while (enough to cause problems with indexing accuracy in fact). Metal spacers don't relax but both metal and plastic spacers can wear thinner if the sprockets start to move around (which they will do, all the time, if the lockring doesn't provide an adequate clamping force).

BTW the combination of new parts, no shim, and metal spacers in the cassette is a poor one; often the lockring stops turning because of the serrations, but if you try to move the sprockets (eg using a par of chain whips) within their backlash on the spline, you will often find that the clamping force isn't really very high.

cheers

[Marcus Aurelius]

The Ultegra lock rings are much more delicate, than a Sora ( for example). So if you aren’t very accurate with the alignment of the threads in the freehub, the ring won’t sit flat, and it will be a bugger to torque up. I use a lock ring tool with an integrated lever, and with Sora and 105 lock rings, it’s just a case of putting the tool into position and tightening, if the rings are slightly askew, the threads pull them straight, this doesn’t happen with the Ultegra lock rings. They are too delicate, so I have to make sure I’m applying a bit of downward pressure, and keep the lever dead level, or the lock ring goes in askew, and it either won’t tighten, or sits in ‘wonky’ which will prevent the wheel / freehub from rotating, without rubbing on the stays.

[Brucey]

the construction of all shimano lockrings is identical; same screw thread, same tolerances etc. The variations are

- OD of lockring (which varies with top sprocket size)
- shim or not
- the depth of engagement (which varies with the number of speeds and the hubs/cassette in use).

If you are worried about cross-threading the lockring, use a separate splined tool (i.e. one without a handle) to wind the lockring in using your fingers. Check it runs true by spinning the wheel before tightening it using a spanner on the tool.

Using a tool with a built-in handle just makes it more difficult to start the lockring using finger pressure only and thus it is easier to cross-thread the assembly with such a tool.

cheers

[Marcus Aurelius]

the construction of all shimano lockrings is identical; same screw thread, same tolerances etc. The variations are

- OD of lockring (which varies with top sprocket size)
- shim or not
- the depth of engagement (which varies with the number of speeds and the hubs/cassette in use).

If you are worried about cross-threading the lockring, use a separate splined tool (i.e. one without a handle) to wind the lockring in using your fingers. Check it runs true by spinning the wheel before tightening it using a spanner on the tool.

Using a tool with a built-in handle just makes it more difficult to start the lockring using finger pressure only and thus it is easier to cross-thread the assembly with such a tool.

cheers

I’m speaking from experience, they are different, and not at all “the same screw thread, tolerances etc” Ultegra are lighter, and more delicate. I think I’ll stick with the ways and with the tools I’ve been doing it with for many years, if that’s okay with you

[Brucey]

I have examined hundreds of lockrings and they are certainly not as you infer them to be. If you were to do as I suggest you might find that your risk of cross-threading them is greatly reduced.

cheers

[Samuel D]

At least some Ultegra lockrings are aluminium rather than steel, which may be what the emperor means by ‘delicate’. More daft gram-saving …

With any screw thread, I start by applying slight axial pressure while screwing it backwards until it clicks, then screwing it in. That way you know you’re not cross-threading it.

[NATURAL ANKLING]

Hi,
I cant tell where the spacer fits from the diagrams and have never seen one too.
On the serrations I tend to grease them, and as I tend to jump on the pedals a lot it normally done up pretty tight.
Which bits does the spacer fit between, that is clamp up onto, faces I presume?

[gxaustin]

I have just checked 7 new cassettes and several older ones with the following results:
Tiagra 10sp, 105 11sp (x2) and Shram - no shim.
However an XT 11sp does have a shim.
Some of my old cassettes have a shim (8sp) but a newish HG51 doesn't have a shim.
Nearly all the locking rings are steel - plated in the case of Shimano, matt black for Shram. My XT and Ultegra rings are different. They are not exactly delicate - but more finely made. Now I've taken the lock ring off I see it does have a very thin shim - so apols for previous duff info. It's so thin it was not visible when screwed up. The Ultegra rings are finished better in dark grey (XT is silver), chamfered at the edges and are non magnetic - lighter than stainless - so Ally? I would have thought ally would be too soft for the torque required. On the other hand if it were Ally that might explain the shim. Titanium maybe? but maybe not Ti since Shimano would have hyped it up presumably?
My conclusion is that the shim has been omitted from many cassettes (the ones with steel lock rings). I know my 9sp and 10sp cassettes currently in use don't have shims as I often remove them for cleaning.

My locking tool has a rod which locates in the wheel spindle and keeps the lock ring square when tightening. As I crank up the torque there is a clicking from the splines but it hasn't done any damage. It may be more critical if you have alloy freehubs - but mine are steel.

If the cassette is Ultegra you can get a new lock ring on Ebay or J E James.

[Samuel D]

All the locking rings are steel - plated in the case of Shimano, matt black for Shram. My Ultegra rings are not exactly delicate - but more finely made. They are finished better in black, chamfered at the edges and are non magnetic - presumably stainless - or could be Titanium?

There’s a contradiction here: first you say they’re all steel, then you say one might be titanium. Which is it?

I think it’s aluminium and therefore, being similarly sized, perhaps a third of the weight of the steel ones.

But maybe Shimano has changed to steel lockrings without the lockring spacer that was included in the past.

[gxaustin]

Now I have taken an Ultegra lockring and an XT lockring off their wheels (they are new but mounted) I tend to agree with you that they are Ally. And they have shims.
The Ultegra ring says 11 speed only but this does not appear on the XT.
Having now removed and replaced the lock ring there is no sign of wear (except to the shim) so hopefully they are adequate