Cassette Spacers.... General Opinion on 11 Speed

[Sea of vapours]

Why would the amount of teeth affect the width of the cassette and the need for a spacer? Doesn't compute for me.

It's because that particular cassette - the Shimano R8000 11-34 road cassette, HG800-11 - explicitly states that it is compatible with 10 and 11 speed freehubs and that it features a 'Hub body designed to fit a variety of bikes from MTB to road bikes * Spacer required to fit hub body to road bikes'. i.e. the HG800-11 is different from other road cassettes, including the other R8000 ones, and definitely does require a spacer when used on an 11 speed hub.
https://bike.shimano.com/en-EU/product/component/ultegra-r8000/CS-HG800-11.html

 

[Chislenko]

For the removal of any confusion the cassette on my road bike is not an 11-34 but a 28.

 

[Ajax Bay]

No doesn't always matter - folk sometimes use a MTB or road hub. The cassettes are different from 11 speed despite spacing and road/MTB hub can be different.

"For the removal of any confusion" freehubs do not come in "MTB" or "road" flavour. Broadly (Shimano) they come in 7sp, 8-10sp and 11sp flavours (plus incompatibly splined 12sp).
It's the 11sp cassettes that come in MTB or 'road' flavours with the odd (see @Sea of vapours exposition above) road one tasting like an MTB one. An 11sp MTB cassette fits on an 8-9-10sp freehub. OR on an 11sp freehub, but with a 1.85mm spacer.

Relja's article "Compatibility [03] Rear hubs" is comprehensive, well illustrated and clear: recommended reading for those who care.

 

[Chislenko]

Anyway, forget and reset the entire conversation!

Took it off today and I was mistaken, there isn't a spacer there.

Doesn't solve my problem of "clunking" and delay though but at least it is clean now.

Have given it a good tighten which previous
experience tells me will eradicate the issue temporarily then I will have to re tighten in a few weeks.

Taking no prisoners, torque wrench up to 50!

 

[faster]

Anyway, forget and reset the entire conversation!

Took it off today and I was mistaken, there isn't a spacer there.

Doesn't solve my problem of "clunking" and delay though but at least it is clean now.

Have given it a good tighten which previous
experience tells me will eradicate the issue temporarily then I will have to re tighten in a few weeks.

Taking no prisoners, torque wrench up to 50!

Have you tried fitting a spacer? The most likely reason for a lock ring coming loose is that a spacer or a larger spacer need to be fitted to prevent the lockring bottoming out on the freehub.

Cassettes don't come loose because there are too many spacers, you just won't be able to start the lockring.

I ignore the rules when it comes to spacers. There is enough variation in freehub length and cassette width to ensure the rules don't always work. If the lockring doesn't bottom out and you can engage the thread of the lockring onto the freehub, you should be fine for spacers.

 

[Ajax Bay]

I ignore the rules when it comes to spacers. There is enough variation in freehub length and cassette width to ensure the rules don't always work.

Would be interesting to hear of your experience of a freehub and cassette combo (make/models) you've used where you shoved a spacer in, "ignoring the rules"? And found the lockring secured the cassette that way whereas without the spacer it bottomed out.

 

[faster]

Would be interesting to hear of your experience of a freehub and cassette combo (make/models) you've used where you shoved a spacer in, "ignoring the rules"? And found the lockring secured the cassette that way whereas without the spacer it bottomed out.

For unrelated reasons, I swap between a pair of cassettes mid way through the life of each chain. I had a pair of supposedly identical cassettes which when swapped onto the same freehub required a different combination of spacers. This swap was carried out a few of times.

What I can't remember is what the actual combination was. It definitely would've been with 9 speed cassettes and it was either a 8/9/10 speed freehub (one cassette required a spacer and the other didn't) or an 11 speed freehub (a different combination of spacers).