Dura Ace 9000 11 speed cassette- rubish product design

[goodboyr]

I suppose all we can do now is wait and see. In the meantime I will continue to ride my wheels with their dura ace and ultegra 11 speed cassettes. I will of course report any failures to this forum.
I could be wrong, but I thought the ultegra chain breakage was due to people using the wrong cleaning solvents which ended up causing stress corrosion cracking in the chain plates.

[4914]

This forum has been very useful and also quite amusing to be honest, I've never posted anything in any forum in the past.
The reason why I did so was to potentially help others as this forum helped me. I found it quite soothing to hear that others had a similar problem to me.
I'll wind it up with this post but, there are a couple of points I’d like to note.

1. The installation instructions don't say, torque down to 40 nm, and after you hear a loud cracking noise, re-torque again to prevent failure.
They say torque to 40nm.

2. I let the LBS install the cassette to protect my warrantee, but as I’m a control freak and I don't trust the bike shop , the first thing I did when I got home was to check that the tension was correct...AND even take it to 50 to be sure.

3. If shimano made 100'000 DA 11 spd cassettes and 1000 of them failed as mine did would they;

A) Send replacement cassettes to those who had problems and hope that there aren’t many more problems and it all blows over?
B) Do a full product recall on a fundamental component of their flagship product which would unquestionably damage there rep?

I love shimano products and I will continue to use them, with the exception of this product.
I think what has happened is that there was a bad run of the products which was already a bad design that has a very small margin of tolerance before failure.

I’m sure shimano will sort it out and I expect the next range will NOT have carbon anywhere in the cassette.

My advice if you have the option if you have trouble or its time to change your cassette anyway is to go for SRAM because in the very worst case situation there is a possibility of failure in a very dangerous situation.
Thanks

[pdlpsher1]

Products recalls on bike parts are fairly common such as this one. I do hope Shimano will take the appropriate actions to remedy the problem.

Voluntary recall by SHIMANO
OF SHIMANO MECHANICAL DISC BRAKE CALIPERS FOR ROAD BIKES: BR-CX75, BR-R515 AND BR-R315

We have identified a safety issue with respect to our mechanical disc brake calipers for road bikes sold after February 2012. The affected models are: BR-CX75, BR-R515 and BR-R315 (sold outside of N. America). No injuries have been reported, but we are voluntarily recalling the affected brake calipers, and are replacing them with improved calipers in which the performance issue no longer exists.


Remedy/Contact: Consumers should stop using bicycles with the recalled brake calipers and bring them to a Shimano authorized retailer in your area for a free inspection and installation of replacement calipers.

For further information, call Shimano American Corp. toll free at 1-800-353-4719 (Monday through Friday 8:00am - 5:00pm PDT)

For Canada, call Shimano Canada LTD. 1-877-377-5211 (Monday through Friday 8:00am - 5:00pm EDT)

[HammerTime2]

1. The installation instructions don't say, torque down to 40 nm, and after you hear a loud cracking noise, re-torque again to prevent failure.
They say torque to 40nm.

2. I let the LBS install the cassette to protect my warrantee, but as I’m a control freak and I don't trust the bike shop , the first thing I did when I got home was to check that the tension was correct...AND even take it to 50 to be sure.

Shimano's directions are to torque to 40 Nm, yet you torqued to 50 Nm. So you didn't follow Shimano's directions, and then the product failed. Perhaps you should only count it as a manufacturer's defect when you have a failure after following the manufacturer's directions. Have you failed to follow Shimano's directions prior to each cassette failure?

Edit: In light of bikerjulio's post below, I partially retract my statements above. However, I would point out that 4914''s item 1. is inaccurate, as Shimano states 30-50 Nm, not 40 Nm as stated by 4914. And yes, if it were my cassette, I would have looked at Shimano's instructions rather than trusting anything posted here.

[11.4]

Reading this thread, I'm trying to understand just how many cassettes have broken. How many different cassettes can be reported as broken, with photos -- not hearsay or whatever. I recall on both BMW and Ford truck forums how there were several 20-30 page threads about high pressure fuel pump failures -- simple self-destruction in the BMWs and failure due to water in the diesel in the Ford trucks. Turns out the BMW ones were real and BMW acted on it with extended warranty protection. The Ford ones could be counted on one hand and there was plenty of evidence that there was actually water-in-the-fuel damage, which Ford declined to cover. I could argue about whether Ford, who supplied a fuel water separator, should have still been liable, but the full stories, when they came out, showed that the Ford drivers had been pretty negligent. So I'd like to understand what Shimano is seeing. So far it doesn't sound like a defective cassette, or I may be missing something.

[pdlpsher1]

Reading this thread, I'm trying to understand just how many cassettes have broken. How many different cassettes can be reported as broken, with photos -- not hearsay or whatever. I recall on both BMW and Ford truck forums how there were several 20-30 page threads about high pressure fuel pump failures -- simple self-destruction in the BMWs and failure due to water in the diesel in the Ford trucks. Turns out the BMW ones were real and BMW acted on it with extended warranty protection. The Ford ones could be counted on one hand and there was plenty of evidence that there was actually water-in-the-fuel damage, which Ford declined to cover. I could argue about whether Ford, who supplied a fuel water separator, should have still been liable, but the full stories, when they came out, showed that the Ford drivers had been pretty negligent. So I'd like to understand what Shimano is seeing. So far it doesn't sound like a defective cassette, or I may be missing something.

So far people have only reported broken carbon spiders and no broken aluminum spiders. If there were equal number of broken carbon and aluminum spiders then this thread would not have been started. It doesn't take a genius to suspect a product/design defect in the carbon spider. And we're not talking about a five year old part with 20,000 miles of use.

[goodboyr]

So far people have only reported broken carbon spiders and no broken aluminum spiders. If there were equal number of broken carbon and aluminum spiders then this thread would not have been started. It doesn't take a genius to suspect a product/design defect in the carbon spider. And we're not talking about a five year old part with 20,000 miles of use.

Well...................I respectfully disagree. It is a big leap of logic to conclude that this is a design defect. If it was a design defect, we would be getting a lot more stories of failures. So, far we have the stories in this thread, and many, many cassettes at both the Ultegra and Dura Ace level with carbon spiders with no reported failures. So, yes, I am not a genius, but even if I was, I doubt I would leap to your conclusion. I for one have not reached any conclusions other than the OP had failures, which may be install issues, or something else. His experience of three in a row with no one else having failures that he's experienced, would lead me to believe that there is something about his situation that is unique, not something common to all cassettes of this type. It could be his wheels, his install, or perhaps the batch of three cassettes his LBS had......I'm just not sure. This thread as stated is very interesting, but this is far from a done deal.

[Nebby]

1. The installation instructions...say torque to 40nm.

2. I...take it to 50 to be sure.

When dealing with carbon parts it's of the utmost importance to follow torque specs as given. I don't know if you only torqued it to 50nm once or for more than one of the cassettes, but it's not surprising to hear that a carbon part failed when it was over-torqued by 25%.

[maxxevv]

I find it strange that you would torque it to 50Nm instead of the instructions 40Nm. ( I can't recall the exact value, so I'll take it that its what's in the instructions.)

You do realise that its Carbon you're dealing with here and not aluminium or steel for that matter ? And that extra 25% of torque you applied has a very real chance of actually damaging the item before you even start using them ?

I suppose you have not tried torquing your car engine's cam cover bolts with an extra 25% torque and over and above the stipulated Loctite compound have you ? Because you may just break the bolt there or worse still strip off the thread on the thread cover and end up with a really expensive retrofit... Since the bolts can't even be drilled out in that case.

Typically in all forms of mechanical thread applications, an experienced mechanic WILL torque the bolt/screw/nut to the specifications in the instructions to +/- 5% (as close as possible in fact, most choose the lower at -5 to-10% instead.) This is to prevent damage to the components in question. If retaining compounds such as Loctite are not specified, then the components in question are 'set to go' for use as stipulated.

However, its also the practice of the good and prudent mechanic to check the items after a short run for loosening or creaking. Its the same with machinery as with bikes, they will check the torque tension again to ensure all's working well. There's often the case of 'bedding-in' of materials such as plastics and soft metals subject to cyclic loads.

In this case, there have been a handful ( less than 5 from the few bike shops I frequent) of cases with this 'creaking' issue. All except 1 have been remedied in time with a simple re-torquing of the lockring. There was one which ended up with a cracked spider as the owner didn't have a clue what was happening nor could he be bothered until it was too late. Note too, that the lockrings were torqued to what was considered a 'safe' value below the stipulated values before the re-tightening.

[bikerjulio]

Shimano's directions are to torque to 40 Nm, yet you torqued to 50 Nm. So you didn't follow Shimano's directions

I find it strange that you would torque it to 50Nm instead of the instructions 40Nm.

When dealing with carbon parts it's of the utmost importance to follow torque specs as given. I don't know if you only torqued it to 50nm once or for more than one of the cassettes, but it's not surprising to hear that a carbon part failed when it was over-torqued by 25%.

As soon as read what OP wrote this morning, my immediate thought was "has he just shot himself in the foot?"

So instead of berating him, I looked up the official Shimano shop instructions for this cassette. http://si.shimano.com/php/download.php?file=pdf/dm/DM-CS0004-01-ENG.pdf

guess what? Instructions say torque to 30-50 NM.

Which seems like a wide range, indicating that the breakage problem may be nothing to do with lockring torque.

[Nebby]

As soon as read what OP wrote this morning, my immediate thought was "has he just shot himself in the foot?"

So instead of berating him, I looked up the official Shimano shop instructions for this cassette. http://si.shimano.com/php/download.php?file=pdf/dm/DM-CS0004-01-ENG.pdf

guess what? Instructions say torque to 30-50 NM.

Which seems like a wide range, indicating that the breakage problem may be nothing to do with lockring torque.

Well go figure! I take my statement back then, I was taking the 40nm figure as fact. My apologies, 4914.

[maxxevv]

Let me requote myself :

I find it strange that you would torque it to 50Nm instead of the instructions 40Nm. ( I can't recall the exact value, so I'll take it that its what's in the instructions.)

[4914]

Nice one Bikerjulio....

Its was the third one that I re-torqued to the now PROVEN maximum torque of 50nm.. after the first two breakages setting at 40nm I too the advice of Trek UK as he stated that the creaking stopped after re torqueing to 50nm...

Still creaked and still broke....

[11.4]

Reading this thread, I'm trying to understand just how many cassettes have broken. How many different cassettes can be reported as broken, with photos -- not hearsay or whatever. I recall on both BMW and Ford truck forums how there were several 20-30 page threads about high pressure fuel pump failures -- simple self-destruction in the BMWs and failure due to water in the diesel in the Ford trucks. Turns out the BMW ones were real and BMW acted on it with extended warranty protection. The Ford ones could be counted on one hand and there was plenty of evidence that there was actually water-in-the-fuel damage, which Ford declined to cover. I could argue about whether Ford, who supplied a fuel water separator, should have still been liable, but the full stories, when they came out, showed that the Ford drivers had been pretty negligent. So I'd like to understand what Shimano is seeing. So far it doesn't sound like a defective cassette, or I may be missing something.

So far people have only reported broken carbon spiders and no broken aluminum spiders. If there were equal number of broken carbon and aluminum spiders then this thread would not have been started. It doesn't take a genius to suspect a product/design defect in the carbon spider. And we're not talking about a five year old part with 20,000 miles of use.

Respectfully, I don't question that at least one cassette has broken. I'd be surprised if Shimano didn't have a very low frequency of breakages in this or any other SKU. It doesn't matter whether it happened in aluminum. It's a question of whether 250,000 cassettes have been sold and 300 broke, or 3. Statistically some WILL break. How many broke, and whether that's outside the predicted breakage rate, is what I'm interested in. Even forks and stems have a small but finite and nonzero breakage rate. Sad, but it just happens. So let's see how many are actually documented and illustrated with images.

[5 8 5]

11.4, have you read the thread?

4914 has three broken cassettes which is downright scary. Glad you're okay.

Thanks to bikerjulio for the link. It's clear that the 9000 and 6800 are different designs and can't be directly compared.
The 9000 sprocket cluster with carbon is a triple while the 6800 is a double.