Is this expected wear and tear?
Comments
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Your misunderstanding here. The lockring torque apllies a clamping force. Pedalling torque has to exceed clamping for the sprocket to move. So if notching occurs do the lockring tighter. Its 40 to 50Nm. Thats also to get the correct sprocket spacing.First.Aspect said:
I wasn't asking whether you should tighten things correctly or not.reaperactual said:
Hear this all the time, ''through experience I can feel how tight something is'👽 or 'I can tell how many P.S.I. in my tyre by pressing it with my thumb' 👽not worth arguing with this logic, I've tried, most responses are 'because torque wrenches and tyre gauges aren't accurate or calibration is off.'First.Aspect said:The torque thing is interesting cycleclinic, but the OP states that he used a torque wrench and 45Nm. I'm struggling, if I am honest, to imagine that a little nylon spacer will offer much resistance, given that nylon is used for bushings (I'm assuming they are nylon in miche cassettes... Could be wrong). But let's go with it.
What sort of variation do you see with torque wrenches? If. For example the OP only hit 35, what sort of difference would that make?
I'd still trust a cheap, badly calibrated or inaccurate torque wrench over the 'stiff door handle' theory 👽 or a cheap pump's gauge over the 'like a firm peach' theory. 👽
As cycleclinic states they know what 40Nm feels like but still use a torque wrench, if they're so sure why bother with the torque wrench?
How often does someone have to tighten something before they can be confident it is as accurate compared to a or torque wrench?
I cracked my carbon bars fitting them by 'feel' that's why I use torque wrenches now and trust them.
So the O.P's torque wrench could be to blame for their notched freehub? 👽
I am struggling to believe that the torque applied to the lock ring could prevent what would surely be a far greater torque applied to the sprockets themselves in use from twisting in relation to the freehub.
Pedaling does not overcome lockring torque. Also you over estimate how strong humans are.
See this link.
https://en.m.wikipedia.org/wiki/Bolted_joint
Note how clamping force is 5x bolt torque divided by bolt diameter. Read the article in full. A torque wrench does not determine preload force. There a wide variation in clamping force for a given torque. Therefore when i say feel is important i really mean it.
When i do a bolt up it not by torque alone. I am not a torque wrench slave. Its a tool but i feel the tread as well. You can feel when the thread is starting to yield. Stop there as the tread will strip beyond that. Essentially if 40Nm does not give the feel required i torque the lockring some more.
To produce 100Nm i have to produce 630W at 60 rpm. The higher the cadance the lower the torque. Gearing further reduces the torque at the wheel. Most road bike gearing is greater than 1:1. Given its separate sprockets that notch ( the triplets tend not too) your gear ratio is then greater than 1:2 so torque is at least halved.
So torque is generally less than 40Nm anyway. Anyone who thinks different is guilty of wishful thinking. Physics does not lie.
Notching is the result of an insufficiently tightened lockring no matter what your torque wrench says. This is not an opinion. It is fact.www.thecycleclinic.co.uk0 -
It's also very interesting. Particularly the amount of torque generated by the chain. You learn something every day.thecycleclinic said:
Your misunderstanding here. The lockring torque apllies a clamping force. Pedalling torque has to exceed clamping for the sprocket to move. So if notching occurs do the lockring tighter. Its 40 to 50Nm. Thats also to get the correct sprocket spacing.First.Aspect said:
I wasn't asking whether you should tighten things correctly or not.reaperactual said:
Hear this all the time, ''through experience I can feel how tight something is'👽 or 'I can tell how many P.S.I. in my tyre by pressing it with my thumb' 👽not worth arguing with this logic, I've tried, most responses are 'because torque wrenches and tyre gauges aren't accurate or calibration is off.'First.Aspect said:The torque thing is interesting cycleclinic, but the OP states that he used a torque wrench and 45Nm. I'm struggling, if I am honest, to imagine that a little nylon spacer will offer much resistance, given that nylon is used for bushings (I'm assuming they are nylon in miche cassettes... Could be wrong). But let's go with it.
What sort of variation do you see with torque wrenches? If. For example the OP only hit 35, what sort of difference would that make?
I'd still trust a cheap, badly calibrated or inaccurate torque wrench over the 'stiff door handle' theory 👽 or a cheap pump's gauge over the 'like a firm peach' theory. 👽
As cycleclinic states they know what 40Nm feels like but still use a torque wrench, if they're so sure why bother with the torque wrench?
How often does someone have to tighten something before they can be confident it is as accurate compared to a or torque wrench?
I cracked my carbon bars fitting them by 'feel' that's why I use torque wrenches now and trust them.
So the O.P's torque wrench could be to blame for their notched freehub? 👽
I am struggling to believe that the torque applied to the lock ring could prevent what would surely be a far greater torque applied to the sprockets themselves in use from twisting in relation to the freehub.
Pedaling does not overcome lockring torque. Also you over estimate how strong humans are.
See this link.
https://en.m.wikipedia.org/wiki/Bolted_joint
Also note how lubrication reduces the
To produce 100Nm i have to produce 630W at 60 rpm. The higher the cadanece the lower the torque. Gearing further reduces the torque at the wheel. Most road bike gearing is greater than 1:1. Given its separate sprockets that notch ( the triplets tend not too) your gear ratio is then greater than 1:2 so torque is at least halved.
So torque is generally less than 40Nm anyway. Anyone who thinks different is guilty of wishful thinking. Physics does not lie.
Notching is the result of an insufficiently tightened lockring no matter what your torque wrench says. This is not an opinion. It is fact.
But your article isn't about torque or, more generally, a shear force applied normal to the direction of the compression force. Preloaded joints are pretty common ways to reduce wear and fatigue. (I drafted a patent application to one last year.) The motion that article is referring to is, I think, normal to the interface, not along it as with the cassette sprocket.
The reference to "fretting" (a term I've not previously encountered) seems to refer to backward and forward motion that creates interfacial damage. I won't pretend to understand exactly what's going on there, but I don't see how it relates to the notching.
So I still don't think it follows that the torque value applied around an axis to secure a knurled lock ring necessarily translates to the torque required to move to other parts around the axis. But I accept that the torque applied via the chain is a lot less than one would think.0 -
Well my reponces should explain why.
1) torquing to 45Nm is not guarantee of sufficient clamping force. There are manufacturing tolerances result in variation in clamping force.
2) op's torque wrench is not calibrated and is telling porkies.
3) dirty threads or deformed threads on the lockring or freehub will result in lower clamping force.
If the clamping force is lower than needed notching results.
Therefore those that blame the product alloy freehub here, are mistaken. Sprocket and spline tolerances are not the issue here. Sadly it is assumption made that causes the problem bere. I could say a bad mechanic too. Mechanics that blame the tools or the product before undertanding the problem and how to remedy it are ones i define as bad mechanics. Every day is a school day.
It is how i present it because thats physics.
I have one bike where i have a proper bodge. The last small sprocket does not engage the splines sufficiently. There is engagement just. Its on a test hub where the geometry meant cassettes fouled the hub flange but i used it anyway to test the general hub design and bearing longevity. The lockring is at 60Nm. The last sprocket can't move and it has not dug in either. Kind of proves the point. The clamping force provided by the lockring holds the sprocket in place. Of course i would never do this on anyones elses bike.
www.thecycleclinic.co.uk0 -
I can pluck random sh#t off the internet too:-
You're using a vector formula with cross product. Let's switch to this:
t = r * F * sin theta, where theta is the angle between your leg and the lever on the sprocket wheel. Theta will change depending on where you are in the cycle of pedaling your bike. Greatest value for sin theta will be when the sprocket crank is horizontal and your leg is perpendicular to it.
For force, use your mass rather than your weight in the formula:
F = m * g
Plugging in the numbers:
F = 65 * 9.81 = 637
t = .17 * 637 * 1 = 108 Nm
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FFS do I use a torque wrench or not?
Or do I stand on the wrench and say, "Yep, that'll do!"?2 -
Don't know anymore, don't care, giving up trying to fix my bike myself I'll take it to Halfords instead. 😭1
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The last sprocket also has a knurled face and is engaged with the lock ring, so it is not comparable to those elsewhere in the cassette. This doesn't demonstrate anything I'm afraid.thecycleclinic said:Well my reponces should explain why.
1) torquing to 45Nm is not guarantee of sufficient clamping force. There are manufacturing tolerances result in variation in clamping force.
2) op's torque wrench is not calibrated and is telling porkies.
3) dirty threads or deformed threads on the lockring or freehub will result in lower clamping force.
If the clamping force is lower than needed notching results.
Therefore those that blame the product alloy freehub here, are mistaken. Sprocket and spline tolerances are not the issue here. Sadly it is assumption made that causes the problem bere. I could say a bad mechanic too. Mechanics that blame the tools or the product before undertanding the problem and how to remedy it are ones i define as bad mechanics. Every day is a school day.
It is how i present it because thats physics.
I have one bike where i have a proper bodge. The last small sprocket does not engage the splines sufficiently. There is engagement just. Its on a test hub where the geometry meant cassettes fouled the hub flange but i used it anyway to test the general hub design and bearing longevity. The lockring is at 60Nm. The last sprocket can't move and it has not dug in either. Kind of proves the point. The clamping force provided by the lockring holds the sprocket in place. Of course i would never do this on anyones elses bike.
(1) the clamping force stops the lockring from working loose by compressing the knurled or keyed surfaces against one another, a bit like those star rings(?) that DT swiss use. But 45Nm applied between the two knurled surfaces won't mean that 45 Nm will be required to move a sprocket. It'll have a bit of an effect by increasing the static friction normal to the compressive force...but how much is unclear (2) possibly, but then again you are working back from your own conclusion, which is bad science (physics is a science) (3) is right I suppose, but presumes that the friction within a dirty thread is significant in comparison to the tightening forces. Just possibly it is negligible.
I don't know what you have in mind when you say "deformed threads".
You quoted a Wikipedia article about "bolts" essentially all of which are pre-tensioned in every application around us. I explained why Wiki wasn't saying what you think.0 -
The intellectual prowess on display here has left me dumbfounded back somewhere on page 2 (when the information was useful to the average Joe like me) and can't and no longer want to attempt to keep up with this d#ck swinging contest'.
Reading recent posts is dropping my I.Q. rather than improving it, after all life is like a box of chocolates and stupid is as stupid does.
If someone wants a lightweight wheelset be aware that the freehub could be made of alloy and one should educate one's self in pros and cons of alloy freehubs. My view is the cons far outweigh the pros of lightness versus durability.
I will continue to use a quality steel freehub, setting my torque wrench to around 40Nm (as per manufacturer recommendations) and am satisfied with the outcome using this method learned using my own personal experiences as my point of reference which I believe is sound advise that is worthy of passing on.👍
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Did you forget to put the spacer behind the cassette?0
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If you tighten the lock ring beyond its recommended torque you are in danger of stripping the threads off the ring.
The weight of the rider and riding low cadences with high torque will put a far greater force through the sprockets onto the freehub body0 -
My money is on a missing spacer.0
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Except gear ratio then reduce that torque number. If you follow my post and all i did explain. The problem with this forum is posts like this. One person tries to explain then another tries to rubbish.reaperactual said:I can pluck random sh#t off the internet too:-
You're using a vector formula with cross product. Let's switch to this:
t = r * F * sin theta, where theta is the angle between your leg and the lever on the sprocket wheel. Theta will change depending on where you are in the cycle of pedaling your bike. Greatest value for sin theta will be when the sprocket crank is horizontal and your leg is perpendicular to it.
For force, use your mass rather than your weight in the formula:
F = m * g
Plugging in the numbers:
F = 65 * 9.81 = 637
t = .17 * 637 * 1 = 108 Nm
Power = torque x 2pi. There js more than one way to do this back of the envelope calculation.
If your gear ratio is 53 -14 then that 1:3.785 so that 100 ish Nm is reduced to 26.42 Nm.
Gears are torque multipliers or reducers. I do understand this. I didn't pluck random shit of the internet. Why lost in this angry manner.www.thecycleclinic.co.uk0 -
deformed threads are damaged ones. That increases friction and therefore reduces the preload applied by the tread.
I have tried explaining the inns and outs here, which no else has done. The rest of you just jumped to say how shit alloy freehubs are.
That does not help the op. It does not explain why the op has a problem and many others don't. I have tried to provide a reasonable explanation as to why.
You still have to explain why I don't get any notching. I can produce as much torque as most people so to has to be something that me and everyone else who does not get notching is doing.
My guess is it dirty or deformed threads. Thats the obvious cause.
Mods close my account and delete every post i have ever made. I and truly done with this forum now. Its not a nice place at all.www.thecycleclinic.co.uk0 -
You have not even been insulted or racially abused yet... wait.thecycleclinic said:
Mods close my account and delete every post i have ever made. I and truly done with this forum now. Its not a nice place at all.
But yes, the "unmoderated" experiment is not very nice
left the forum March 20230 -
Thecycleclinic my post was only to point out that although I don't doubt your exceptional knowledge it is too much in depth the the average user to comprehend in my opinion,thecycleclinic said:deformed threads are damaged ones. That increases friction and therefore reduces the preload applied by the tread.
I have tried explaining the inns and outs here, which no else has done. The rest of you just jumped to say how censored alloy freehubs are.
That does not help the op. It does not explain why the op has a problem and many others don't. I have tried to provide a reasonable explanation as to why.
You still have to explain why I don't get any notching. I can produce as much torque as most people so to has to be something that me and everyone else who does not get notching is doing.
My guess is it dirty or deformed threads. Thats the obvious cause.
Mods close my account and delete every post i have ever made. I and truly done with this forum now. Its not a nice place at all.
My response was only in fact meant so you would hopefully respond and get your point across in a more simplified manner that I could understand which you did.
We all have our opinions and I use my experiences as my way of giving information to others, right or wrong, who are in a similar situation, to promote debate and give another view point.
This is not a personal attack aimed at you or anyone in particular. If you think that I am sorry you feel this way and I was also being very immature in my responses I am sorry for that too.
You're conclusions of the notching issues are valid, I believe my conclusion is too. I won't respond or quote any comments you make on threads in the future.
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I still think it's a spacer missing.0
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On a road bike, the max torque applied through the smallest (and not actually relevant here) sprocket is about 100Nm (11T assumed, I know it can be bigger) as you go down the gears that rises.
So lets use a fairly typical road cassette of 12-28 10 speed.
9th is 13T - 120Nm
8th is 14T - 127Nm
7th is 15T - 136Nm
That's a lot of torque to try and hold in place with smooth steel sandwiched between nylon spacers (no spider) usually for these gears). and the sprockets are only 1.6mm thick. Ref the comment above about pins, they make no difference, only spiders spread the load properly.Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.1 -
Its simple, the splines on a soft aluminium freehub body are softer than the material the cassette is made from. Note on your shimano hubs that it is the metal cogs that dig in not the ones on the carrier which also spreads the load through a wider contact point.
You would have to tighten it up beyond the recommended torque to avoid this and it would probably just mash the threads on the freehub before you achieved anything. It's something you'll have to live with. BTW the recommended torque range for a shimano cassette is 30 - 50nm not specifically 40nm.
By all means go for 50 or more but it doesn't make much difference to the digging in. Just tidy up a bit with a file.1
