Shimano cassette lock rings with more threads?

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Brucey
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Re: Shimano cassette lock rings with more threads?

Post by Brucey »

isn't that enough?

cheers
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Gattonero
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Re: Shimano cassette lock rings with more threads?

Post by Gattonero »

Cugel wrote:The hub is an 11-speed hub, with a width of 36.75mm as measured by my trusty vernier. This is identical to another 11-speed hub I have, on which the cassette in question will fit with the lock ring engaging at least two of it's threads. (Still not enough really but it does hold) .....

So, it is something of a mystery why the lock ring won't engage to the Hunt wheel's freehub. I can only assume that the female threads on the Hunt freehub don't come out as far as those on the other hub into which the lock ring will screw.

No, I haven't accidentally put the 8/9/10 cassette 1mm spacer behind the 11-speed cassette. It's safely in the spares box with the other 1528 spares. :-)

I have squished the cassette sprockets and spacers quite firmly to ensure that they're fully on the freehub. The smallest sprocket is engaging the splines of the Hunt freehub (just) in an identical fashion to how it engages the splines on the other 11-speed hub into which the lock ring will screw.

****
There's no other solution that I can see other than obtaining a lock ring with more/deeper threads. Does anyone have a (12 sprocket) Token or similar alloy bling lock ring lying about on which they could measure the depth of the threaded protrusion?

Cugel


Sram alluminium lockrings seem to be just so slightly deeper.
Still, I'd check there's no dirt/grime in between the sprockets, often that is enought to not make the sprockets engage well. Also, the "40Nm" for the lockring is a value that's too high, you can do with 25-30Nm
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Re: Shimano cassette lock rings with more threads?

Post by Brucey »

25-30Nm on an aluminium freehub body is the sort of thing that allows the cassette to 'bite' into the freehub body. However I agree that you don't have much choice if the parts are so badly made that you only get one or two threads engaged.

There is a reason that most shimano freehub bodies and lockrings are made in steel....

cheers
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Cugel
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Re: Shimano cassette lock rings with more threads?

Post by Cugel »

Gattonero wrote:Sram alluminium lockrings seem to be just so slightly deeper.
Still, I'd check there's no dirt/grime in between the sprockets, often that is enought to not make the sprockets engage well. Also, the "40Nm" for the lockring is a value that's too high, you can do with 25-30Nm


I've checked for grime by polishing every sprocket and spacer. (Well, not quite - but they have been thoroughly cleaned).

The 40Nm is justified, as Brucey mentions, because it squeezes the individual sprockets and spacers together hard enough to avoid one sprocket slipping agin' t'others and thus exerting a concentrated pressure on an alloy freehub to bite into the splines. In truth, even when all the sprockets do act as one, alloy freehub splines do still get bitten - although the bites are less severe as the biting force of one's pedal thrusts are spread out over all 10 or eleven sprockets.

I do have a number of alloy freehubbed wheels, all of which have bite marks but none of which are troublesome enough to stop the cassette from going on and off the freehub. Much more severely bitten freehubs may be viewed on the interwebbing, presumably because the installers failed to apply the full forty Newtons and so each individual cog applied it's own bite.

Personally I would prefer to have at least the freehub splines made of steel; but the more upmarket wheels all seem to have alloy freehub bodies, presumably because of the obsession with even tiny weight differences. The Hunt's have a single steel spline bonded to the otherwise alloy freehub, supposedly to prevent or reduce the bite effect. I'll do a few hundred miles then have a look.

Cugel
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Cugel
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Re: Shimano cassette lock rings with more threads?

Post by Cugel »

Brucey wrote:isn't that enough?

cheers


No. :-)

What if we rejected all other aspects of the physical world because they were less than perfect? One would have to live in space, where even the odd neutrino or gamma ray might prove a nuisance and have to be sent back. I prefer to find a fix to these small problems and so stay fully installed within the admittedly trying world.

Cugel
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Cyril Haearn
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Re: Shimano cassette lock rings with more threads?

Post by Cyril Haearn »

Brucey wrote:25-30Nm on an aluminium freehub body is the sort of thing that allows the cassette to 'bite' into the freehub body. However I agree that you don't have much choice if the parts are so badly made that you only get one or two threads engaged.

There is a reason that most shimano freehub bodies and lockrings are made in steel....

cheers


Made in steel, what is the reason please?
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Gattonero
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Re: Shimano cassette lock rings with more threads?

Post by Gattonero »

Cugel wrote:
Gattonero wrote:Sram alluminium lockrings seem to be just so slightly deeper.
Still, I'd check there's no dirt/grime in between the sprockets, often that is enought to not make the sprockets engage well. Also, the "40Nm" for the lockring is a value that's too high, you can do with 25-30Nm


I've checked for grime by polishing every sprocket and spacer. (Well, not quite - but they have been thoroughly cleaned).

The 40Nm is justified, as Brucey mentions, because it squeezes the individual sprockets and spacers together hard enough to avoid one sprocket slipping agin' t'others and thus exerting a concentrated pressure on an alloy freehub to bite into the splines. In truth, even when all the sprockets do act as one, alloy freehub splines do still get bitten - although the bites are less severe as the biting force of one's pedal thrusts are spread out over all 10 or eleven sprockets.

I do have a number of alloy freehubbed wheels, all of which have bite marks but none of which are troublesome enough to stop the cassette from going on and off the freehub. Much more severely bitten freehubs may be viewed on the interwebbing, presumably because the installers failed to apply the full forty Newtons and so each individual cog applied it's own bite.

Personally I would prefer to have at least the freehub splines made of steel; but the more upmarket wheels all seem to have alloy freehub bodies, presumably because of the obsession with even tiny weight differences. The Hunt's have a single steel spline bonded to the otherwise alloy freehub, supposedly to prevent or reduce the bite effect. I'll do a few hundred miles then have a look.

Cugel


Having fitted many thousands cassettes let me tell you: it's theory that hardly meets the real world. You can tighten the lockring even to 60Nm if you were able to, still getting the cassette to mark the alluminium freehub bodies. The reason is that they were never meant to be alluminium in the first place (there could be a lot to talk aobut this, just ask yourself why Campagnolo went from shallow splined on the 8sp cassettes on steel freehubs, to deep splines of the 9/10sp cassettes which had alluminium bodies) in fact Shimano has never done a proper HG freehub (except the short-lived "HG10") out of alluminium, always steel or titanium. There ought to be a reason!

By tightening to 40Nm you are only getting close to strip the threads of the alluminium freehub, nothing else.
Btw, the steel insert on the Hunt wheels (TW hubs) IIRC is from an original American Classic idea. It does work a bit, you still get marks on the freehub but they don't go far
It is by riding a bicycle that you learn the contours of a country best,
since you have to sweat up the hills and coast down them.
Thus you remember them as they actually are...
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Cugel
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Re: Shimano cassette lock rings with more threads?

Post by Cugel »

Gattonero wrote:Having fitted many thousands cassettes let me tell you: it's theory that hardly meets the real world. You can tighten the lockring even to 60Nm if you were able to, still getting the cassette to mark the alluminium freehub bodies. The reason is that they were never meant to be alluminium in the first place (there could be a lot to talk aobut this, just ask yourself why Campagnolo went from shallow splined on the 8sp cassettes on steel freehubs, to deep splines of the 9/10sp cassettes which had alluminium bodies) in fact Shimano has never done a proper HG freehub (except the short-lived "HG10") out of alluminium, always steel or titanium. There ought to be a reason!

By tightening to 40Nm you are only getting close to strip the threads of the alluminium freehub, nothing else.
Btw, the steel insert on the Hunt wheels (TW hubs) IIRC is from an original American Classic idea. It does work a bit, you still get marks on the freehub but they don't go far


I bow to your extensive experience (always a better teacher than mere theory) but I have to say that tightening the lock ring as much as one can seems to stop individual sprockets from biting so hard on alloy freehub bodies. As I mentioned, I have a several in which the alloy freehub is bit but the bites are small and even across all sprockets-splines, including those in any clusters of two or three at the big end.

There are a lot of pics and stories about on the web indicating alloy freehubs with deeper bites, in which the cassette is very hard to get off .... or on again without some filing away of the distorted alloy around the deep bites. I've never had that problem, despite putting some severe stomps through the cassette.

****
The puzzle is: why do Shimano make the lock ring so short? I've now fettled my Hunt lock ring problem by using a Token alloy lock ring, which arrived this morning. It's only 1mm longer than the steel Shimano lock ring and comes nowhere near bottoming inside the freehub before tightening on the smallest sprocket - but the extra 1mm of length means that the threads engage properly, both when starting the insertion/turn and when reaching full tightness. I'm presuming that having enough thread for a proper start also means that the lock ring squishes the cassette sprockets and spacers a bit more thus making even more lock ring-to-freehub thread engage.

***
I recall the early cassette clusters from Shimano (7-speed, in the early 90s) where the cluster was bolted together with three long thin bolts going from the big sprocket through all the others to screw into small threaded holes in the smallest sprocket. Nowadays the less expensive Shimano cassettes have a similar arrangement using riveted pins. Presumably the function of these is to transfer the forces applied from chain to sprocket across the whole cassette and it's splines ..... ?

****
Anyroadup, the Hunt Wheels with their tubeless Schwalbe G 300mm tyres are now fully installed and a joy to ride both up & down the filthy scabby lanes. These are my first tubeless tyres and I'm looking forward to discovering their advantages and the other sort of vantages. :-)

Cugel
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Brucey
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Re: Shimano cassette lock rings with more threads?

Post by Brucey »

Cugel wrote:
Brucey wrote:isn't that enough?

cheers


No. :-)

What if we rejected all other aspects of the physical world because they were less than perfect? One would have to live in space, where even the odd neutrino or gamma ray might prove a nuisance and have to be sent back. I prefer to find a fix to these small problems and so stay fully installed within the admittedly trying world.

Cugel


if it can be easily fixed fair enough but otherwise you have a set of wheels that are about as much use a chocolate teapot...

BTW cassette lockrings are funny blighters because

1) the tightening torque does not translate to the gripping force (because of the serrations)

2) there is a loss of gripping force because the plastic spacers settle and creep. Cassette lockrings often need to be retightened to maintain gripping force.

I got so bored of retightening cassette lockrings that I started making my own metal spacers for HG cassettes, before they were even an option on standard parts. No signs of any marking on correctly tightened parts.

I think that the best option may be to install a lockring without serrations, on a cassette with metal spacers, and use some threadlock on the lockring threads. You have a fighting chance of everything staying tight that way

cheers
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Mr Evil
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Re: Shimano cassette lock rings with more threads?

Post by Mr Evil »

Cugel wrote:...Personally I would prefer to have at least the freehub splines made of steel; but the more upmarket wheels all seem to have alloy freehub bodies, presumably because of the obsession with even tiny weight differences...

There are a small number of "upmarket" hubs with either titanium or steel freehub bodies. In particular I know that absolute black hubs have steel freehub bodies, yet are of comparable weight to hubs with aluminium ones. Disc and 142mm spacing only though.

Brucey wrote:...there is a loss of gripping force because the plastic spacers settle and creep...

Cugel mentioned an Ultegra cassette, which come with aluminium spacers.

Another problem with tightening lockrings is that it's rare to find a lockring tool with square drive for use with a torque wrench. They exist, but Shimano themselves don't make one.
Valbrona
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Re: Shimano cassette lock rings with more threads?

Post by Valbrona »

I would expect Hunt to build with Novatec hubs: http://www.bdopcycling.com/HUBS-ROAD.asp
I should coco.
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Gattonero
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Re: Shimano cassette lock rings with more threads?

Post by Gattonero »

Cugel wrote:
Gattonero wrote:Having fitted many thousands cassettes let me tell you: it's theory that hardly meets the real world. You can tighten the lockring even to 60Nm if you were able to, still getting the cassette to mark the alluminium freehub bodies. The reason is that they were never meant to be alluminium in the first place (there could be a lot to talk aobut this, just ask yourself why Campagnolo went from shallow splined on the 8sp cassettes on steel freehubs, to deep splines of the 9/10sp cassettes which had alluminium bodies) in fact Shimano has never done a proper HG freehub (except the short-lived "HG10") out of alluminium, always steel or titanium. There ought to be a reason!

By tightening to 40Nm you are only getting close to strip the threads of the alluminium freehub, nothing else.
Btw, the steel insert on the Hunt wheels (TW hubs) IIRC is from an original American Classic idea. It does work a bit, you still get marks on the freehub but they don't go far


I bow to your extensive experience (always a better teacher than mere theory) but I have to say that tightening the lock ring as much as one can seems to stop individual sprockets from biting so hard on alloy freehub bodies. As I mentioned, I have a several in which the alloy freehub is bit but the bites are small and even across all sprockets-splines, including those in any clusters of two or three at the big end.
....


There isn't anything to bow, rather to learn from many different situations.
From the 4 guys that went onto crossing South America, to the guys racing crits, the humble commuter in the streets of London, or those lads that ended up drafted by Team Wiggins and Team Sky. Truth is: the loose sprockets have no means of connection to each other on the sides, in fact are quite smooth, what's gonna do 40Nm to keep them steady altogether when you have lad that can crank up 1Kw?
There are too many variables, but it ends always the same way, the HG freehub was never meant to be made out of alluminium, so using loose sprockets one has to expect more or less deep marks on it. And to be fair, I'm yet to see a freehub that has become unusable just because of those marks, even the deepest ones are unlikely to cause a fracture per se.
Usually on such freehubs, is the pawl pockets that would fatigue and stretch (the the pawls won't engage properly, and so on) well before a crack along the freehub will appear.
It is by riding a bicycle that you learn the contours of a country best,
since you have to sweat up the hills and coast down them.
Thus you remember them as they actually are...
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RickH
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Re: Shimano cassette lock rings with more threads?

Post by RickH »

Mr Evil wrote:Another problem with tightening lockrings is that it's rare to find a lockring tool with square drive for use with a torque wrench. They exist, but Shimano themselves don't make one.

Oh yes they do! (In best panto voice as its nearly that time of year! :D )

CRC link. I got one, via my LBS, so I could get the Centrelock disc off an Alfine hub & it claims to be genuine Shimano.
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Brucey
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Re: Shimano cassette lock rings with more threads?

Post by Brucey »

Gattonero wrote:
Cugel wrote: but I have to say that tightening the lock ring as much as one can seems to stop individual sprockets from biting so hard on alloy freehub bodies. As I mentioned, I have a several in which the alloy freehub is bit but the bites are small and even across all sprockets-splines, including those in any clusters of two or three at the big end.
....


.... what's gonna do 40Nm to keep them steady altogether when you have lad that can crank up 1Kw?....


I agree with Cugel; there is a point that has been missed here, (and I am repeating myself, not for the first time....) which is that clamping force on the sprockets is not closely related to the torque on the lockring if the cassette spacers settle in any way and/or the lockring is serrated.

The torque required for 'one serration more' can be huge yet the clamping force can still be insufficient. If the same torque were applied to a conventional fastener (without serrations), the clamping force would be several tonnes, and even with a modest coefficient of friction the sprockets would not move under normal pedalling forces.

You might argue that when a strong rider goes for it the forces are higher than normal but even so I don't think that this causes the movement in 'well bitten' freehubs; it is quite apparent that the sprockets must be on the move nearly all the time rather than only when a full sprint is underway; the pattern of wear is exactly matched by the wear on the sprockets, so is due to frequency of use rather than peak load in any one gear (and yes the two are not the same).

If you want further proof that this is correct, take a look at a well-used UG freehub; it typically won't show any bite or wear marks at all; the sprockets are held very well by the clamping forces. The sprockets never get a chance to work loose because the threaded top sprocket tightens itself every time you use top gear. Such self-tightening is less than would be achieved using a tool, yet it is nearly always sufficient. IME if the top sprocket is tightened using a tool, and metal spacers are used between the sprockets, the sprockets don't move at all, even under the most violent use.

There is a fly in the ointment though; it is doubtful that an aluminium freehub body won't lose it's threaded end or that the thread won't strip if it is tightened to an amount that is quite acceptable for a steel freehub body.

cheers
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Mr Evil
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Re: Shimano cassette lock rings with more threads?

Post by Mr Evil »

RickH wrote:Oh yes they do! (In best panto voice as its nearly that time of year! :D )

CRC link. I got one, via my LBS, so I could get the Centrelock disc off an Alfine hub & it claims to be genuine Shimano.

Thanks. I probably didn't find that because I was looking for 1/2" drive to fit my big torque wrench.

I originally wanted one because I was fed up of sprockets digging into the cassette body, sometimes deep enough that I needed two chain whips to remove them. After I got an appropriate tool and tried tightening it up to the full 40Nm, I found that it didn't really make any difference (even with aluminium spacers).

Curiously, the lockring for the hub I linked to above has finer pitched thread than a standard lockring, and no serrations.
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