SRAM Eagle Cracked Chain Plates

[MudLark]

Could just be a slight misalignment of the derailleur under the sprocket. Possibly tuned out with the barrel adjuster.

the 2 misaligned teeth on affected cassettes were quite obvious to those who know what to look for. Maybe get your lbs to check it over as well

 

Thank you very much Diesel – both for the reassurance and for the suggestion around the barrel adjuster. Much appreciated.

[droo]

15 years on and we're having the exact same arguments here.

 

It's nice to know that the more things change, the more they stay the same.

 

It's like you never left...

[DieselnDust]

From what I read, SRAM seems to have some quality & specifically tolerance issues. Hambini's opinion of their GX crankset is not suitable for younger viewers.

 

I also find it interesting that no one's yet referenced the recent Velonews article on chain wear. I found both SRAM & Shimano's responses very unsatisfactory. 

 

https://www.velonews.com/gear/we-went-to-germany-to-test-the-most-popular-bicycle-chains-heres-what-we-found/

  

We went to Germany to test the most popular bicycle chains. Here’s what we found:

 

We're talking 12 speed and you bring in 11 speed.....ai ai ai.

 

Its a hogwash study anyway. The sample number is way too small to tell you anything other than write a story for a sheeple magazine

Edited June 12, 2020 by DieselnDust

[MudLark]

Anyway, probably the single biggest factor is how you take care of your chain – or don't, as the case may be.

Edited June 12, 2020 by MudLark

[PhilipV]

I say this to everyone taking part in the discussion. If you want to argue technical points, you have to be technically correct.

You must be a hoot at parties.

[hansolo]

If we can’t comment on adverts can we at least get some proper technical content for all the armchair experts to disagree with? A few articles on geometry, chain wear (or stretch), suspension designs. etc. would be super.

 

If these articles were to be published on a Friday morning it would be even better.

Edited June 13, 2020 by hansolo

[MudLark]

Question here: Why does a chain get longer with use? I was looking at the components. The rollers ride on a stamped shoulder that is part of the inner plates. There's no contact between the roller and the pin. None. So the wear is between the roller and the plate shoulder. So the distance between two rollers will increase over time - which is what a lot of chain gauges measure. But given that, why does the chain as a whole also become longer then? What wears?

Edited October 11, 2020 by MudLark

[Skylark]

Question here: Why does a chain get longer with use? I was looking at the components. The rollers ride on a stamped shoulder that is part of the inner plates. There's no contact between the roller and the pin. None. So the wear is between the roller and the plate shoulder. So the distance between two rollers will increase over time - which is what a lot of chain gauges measure. But given that, why does the chain as a whole also become longer then? What wears?

The rollers and pins wear which allows the chain to elongate.

[MudLark]

The rollers and pins wear which allows the chain to elongate.

Thanks Skylark, but there's no contact between the rollers and the pins. And thus apparently no wear on the pins. Only between the roller and inner plate shoulder (take a chain apart and you will see what I mean [emoji3166]). Further, if you press out a pin on a worn chain, it seems to require as much force as on a new chain. So why does the chain nevertheless get longer overall?

[droo]

The inner plates pivot on the pin, and both inner plate and pin wear over time.

[MudLark]

Droo, probably right.The pin goes through both inner and outer plates. But one set of plates has to be able to rotate on the pin. So presumably the inner plate holes are very slightly larger than those in the outer plates (in which the pin is "secured"). Thus there is a wear interface between the pin and inner plate which may increase in size with time - possibly even becoming somewhat oval. And thus the chain over time becomes fractionally longer. That would seem to be the most rational answer.

[DieselnDust]

Droo, probably right.The pin goes through both inner and outer plates. But one set of plates has to be able to rotate on the pin. So presumably the inner plate holes are very slightly larger than those in the outer plates (in which the pin is "secured"). Thus there is a wear interface between the pin and inner plate which may increase in size with time - possibly even becoming somewhat oval. And thus the chain over time becomes fractionally longer. That would seem to be the most rational answer.

 

 

The innre plates rotate on the pin.

The outer plates locate the pin.

The roller roller rolls over the pin and the chamfered edges of the inner plates

The rolling element is the rolller.

When the roller wears the pin out the inner plates have a linear displacement under load that you see as"Chain stretch"

 

none of the plates have stretched. Steel is elastic. For you to exert a force strongenough to pull the plates material beyond the elastic limit well ya..... how much drugs are you taking bru #asking for my palLance