SRAM Eagle Cracked Chain Plates

[Bondinator]

I had the exact same problem on my GX eagle chain towards the end of last year. The chain had hardly seen 1000kms and was always washed and lubed after every ride. The chain wasn't even at 0.5 wear yet. 

 

The LBS that I had bought the chain from had closed down two months before the chain snapped and the other bike shops laughed at me when I mentioned a warranty replacement. I had to buy a new chain and I am watching it like a hawk now.

Edited May 20, 2020 by Bondinator

[boesman88]

The one on the left is the newer and improved design.

 

 

I have the older one.  

[gummibear]

New chain and wheels should do the trick.

[ChrisF]

The one on the left is the newer and improved design.

 

 

2018/19 bikes were shipped with the gears on the RIGHT.

 

 

Never had issues with the chain ...

[capediver]

You okes wash your chains too much.....YOU WASHED IT THIN!...(that's my theory.)

[BaGearA]

Those saying bad material just think about it quick. SRAM makes hundres of thousands of chains selling them to everyone as a consumable as they wear quick and gets replaced often

 

If there were a defect of this magnitude there would be hundreds of claims of faulty chains as they dont switch material after every chain being made to a new batch of material.

Okay sure but what if a tempering oven had a fault on that wasn't detected until 12 batches were run through it, but in reality the fualt was there for 16 batches and those 4 made it to the consumers

 

Not saying maintenance can't be the guilty party but I've seen people who take little to no care of their bikes and this type issue wasn't present

Edited May 20, 2020 by BaGearA

[boesman88]

You okes wash your chains too much.....YOU WASHED IT THIN!...(that's my theory.)

 

 

that is exactly what I concluded hahaha 

[MORNE]

do you do wax baths to lube your chains?....You are not supposed to do it in a furnace

 

PS: you know you went a bit over when the chain is glowing haha.

Edited May 20, 2020 by morneS555

[RiverInTheRoad]

You either have a manufacturing error or something is abrading your chain. Check every tooth on your cassette and chainring for sharp edges.

[Dicky DQ]

Has this happened to anyone else? +/-2000km of riding and 10+ of the chain plates have started cracking and shearing around the pins? I only noticed this after I snapped the chain. Bike is always kept in pristine condition.

 

Very annoying especially during lock down as I cannot replace it until shops open up :-|

The shops are all open, well the ones I have been to or past.

[i24]

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I notice that the top right quadrant of every link is chamfered. Is this chain directional? Ie is it designed to be installed with a specific side facing towards the sprocket or towards the wheel? Or are those wear marks?

 

 

Do you take off the chain off the bike for cleaning? Maybe it has been overwashed, perhaps with a solvent which has caused stress corrosion cracking.

 

If it is due to a manufacturing fault we should hear other reports of similar failures.

[DieselnDust]

2018/19 bikes were shipped with the gears on the RIGHT.

 

 

Never had issues with the chain ...

 

 

Pretty sure that those are just the bottom pulley wheel and the top guide pulley wheel. My 2018 XX1 derailleur and 2017 X01 rear derailleur have exactly the same pullley wheels.

 

The cause of the chain failure is likely due to the die that is used to punch the chain plates being at end of life. Those tools wear out and when they do the hole they punch out is too small. Drive a pin into a smaller hole and you end up with excessive tensile stresses in the plate. There;s probably a bunch of those chains out there that weren't caught by the time the die was measured for non conformance.

 

I doubt you will get a warranty replacement but its worth a try as that is not a normal failure by a long shot. Plastic pulley wheels have nothing to do with the problem.

[DieselnDust]

I notice that the top right quadrant of every link is chamfered. Is this chain directional? Ie is it designed to be installed with a specific side facing towards the sprocket or towards the wheel? Or are those wear marks?

 

 

Do you take off the chain off the bike for cleaning? Maybe it has been overwashed, perhaps with a solvent which has caused stress corrosion cracking.

 

If it is due to a manufacturing fault we should hear other reports of similar failures.

 

 

The chain is not directional.

that is also not stress corrosion cracking. The links that have broken are nickel coated. The cracks are occuring in the same place where there is high stress so I suspect its just over stressed due to the hole being to small for the pin.

[boesman88]

Pretty sure that those are just the bottom pulley wheel and the top guide pulley wheel. My 2018 XX1 derailleur and 2017 X01 rear derailleur have exactly the same pullley wheels.

 

The cause of the chain failure is likely due to the die that is used to punch the chain plates being at end of life. Those tools wear out and when they do the hole they punch out is too small. Drive a pin into a smaller hole and you end up with excessive tensile stresses in the plate. There;s probably a bunch of those chains out there that weren't caught by the time the die was measured for non conformance.

 

I doubt you will get a warranty replacement but its worth a try as that is not a normal failure by a long shot. Plastic pulley wheels have nothing to do with the problem.

 

Now this is a post that makes sense.  Thank you for this.

 

The point for me is that its just a chain and a couple of buck will fix the problem, so I have no interest in ranting or accusing. I am just very curious as to why this happened.  I'm new to SRAM, so its an interesting problem to need to understand both from a perspective of why the heck it happened, but also form a perspective of how this influences my future product choices.  Perhaps the Japanese brands have stricter policies with regards to machine tolerances and age analysis than newer brands? its certainly the case with Toyota isnt it?

[DieselnDust]

Now this is a post that makes sense.  Thank you for this.

 

The point for me is that its just a chain and a couple of buck will fix the problem, so I have no interest in ranting or accusing. I am just very curious as to why this happened.  I'm new to SRAM, so its an interesting problem to need to understand both from a perspective of why the heck it happened, but also form a perspective of how this influences my future product choices.  Perhaps the Japanese brands have stricter policies with regards to machine tolerances and age analysis than newer brands? its certainly the case with Toyota isnt it?

 

 

The SRAM Chains are made in Taiwan and I suspect by KMC. Used to be SACHS back in the day but most chains are made in Taiwan or Mainland China. I've never seen a failure that so consistent in a chain before so I strongly suspect its just a bad batch that crept through. In production the stamping tools only get checked on a frequency basis and that's informed by retained plates that get measured with a go no-go gauge. Those plates are merely samples of many thousands of plates that are stamped per minute so its easy to see how the worn die would not be caught early. Generally the system works and the fact that you don't see this type of failure often bares this out. 

 

I would advise you get the XX1 chain though. It'll last you up to 6000km in my experience.

[boesman88]

The SRAM Chains are made in Taiwan and I suspect by KMC. Used to be SACHS back in the day but most chains are made in Taiwan or Mainland China. I've never seen a failure that so consistent in a chain before so I strongly suspect its just a bad batch that crept through. In production the stamping tools only get checked on a frequency basis and that's informed by retained plates that get measured with a go no-go gauge. Those plates are merely samples of many thousands of plates that are stamped per minute so its easy to see how the worn die would not be caught early. Generally the system works and the fact that you don't see this type of failure often bares this out.

 

I would advise you get the XX1 chain though. It'll last you up to 6000km in my experience.

This was going to be my next question - which chain next?