Ultegra rear mech snapped on me

mr.b-campag

Thanks gents, glad to hear I'm not the only one who thinks this wasn't quite right. Already had a DA rear mech that I had lying around fitted.

Btw big up to the mechanic at Decathlon Wandsworth who did a great job getting me back on the road last night.

darkhairedlord

PhotoNic69 wrote:

Hmmm. That is one snapped derailleur all right! That alloy should never have broken before the hanger snapped or bent. Would be impossible to tell from a photo what the cause is. Might be corrosion around the hinge or a very sharp impact or manufacturing fault.

Send it back to Shimano. Buy a new one while you wait. If they say you can claim then get some money back. If not you have bought yourself a new hanger. Same result -you can keep on riding.

Assumes the hanger has been designed correctly.

sniper68

For those of you without Flickr:-



I can honestly say I have only ever experienced a similar snappage on a Shimano XTR but that was due to impact.

StillGoing

Is there an image of the B knuckle section that we can only see the inside of?

jgsi

Sorry mate, but something just does not add up in your story after seeing the actual damage.
As mentioned - impact.

mr.b-campag

For those of you without Flickr:

Thanks Sniper.

Is there an image of the B knuckle section that we can only see the inside of?

Sorry I'm not exactly sure what you're referring to, but I will put the other pics up I have on to flickr, though I fear they will be much the same (and yes I have other things to do in my life besides this!).

Sorry mate, but something just does not add up in your story after seeing the actual damage.
As mentioned - impact.

I must admit I'm puzzled by some of the responses on here - though at least you're polite. If I'd had an impact that caused my rear mech to break like that I can assure you that is the last thing I'd be worried about (most likely from a hospital bed).

What exactly do you think is in this for me? That I might get a 'free' rear mech that retails for forty quid (or whatever)? I could post the receipts that show it has already cost me more than that (not that I give a toss for forty quid), but no doubt you (pl.) would say they are fake or some such. Are some of you afraid I might pull the wool over one of you self-appointed sleuths?

As others have said Shimano are almost certainly not going to give me anything in any case, never mind admit any liability. At best this might, just might, be another data point for their engineers to bear in mind when re-designing these things.

I know one is not supposed to feed the trolls, but I just don't understand some of the behaviours exhibited on here. Again, thanks to those of you who have engaged constructively here.

Tiesetrotter

They make millions of these. At some point, there is always going to be a flaw in the alloy. Looks like you got it.

I have had a Look spindle sheer off as I was pedaling which was quite amusing really. Sent it back to Look just to get their opinion. They sent me replacement Keo blades and an apology which I wasn't expecting. I explained they had been in a couple of offs. But they looked at it and said they thought there was a flaw in the metal.

Worst I had was a snapped chain, a pretty new one. I was going up a very steep little climb. It wrapped around my SR rear mech and ripped it to shreds. Plates, jockey wheels, ceramic bearings littered all over the road. Not a cheap day. Shit happens.

davidof

Ok I'll go with my original hunch that it is a manufacturing defect, some flaw the the forging, maybe that little shiny error caused some stress or weakness. I've seen a lot of these kind of things in ski bindings.

milemuncher1

Tiesetrotter wrote:

They make millions of these

Of course

StillGoing

Mr.B-Campag wrote:

For those of you without Flickr:

Thanks Sniper.

Is there an image of the B knuckle section that we can only see the inside of?

Sorry I'm not exactly sure what you're referring to, but I will put the other pics up I have on to flickr, though I fear they will be much the same (and yes I have other things to do in my life besides this!).

Sorry mate, but something just does not add up in your story after seeing the actual damage.
As mentioned - impact.

I must admit I'm puzzled by some of the responses on here - though at least you're polite. If I'd had an impact that caused my rear mech to break like that I can assure you that is the last thing I'd be worried about (most likely from a hospital bed).

What exactly do you think is in this for me? That I might get a 'free' rear mech that retails for forty quid (or whatever)? I could post the receipts that show it has already cost me more than that (not that I give a toss for forty quid), but no doubt you (pl.) would say they are fake or some such. Are some of you afraid I might pull the wool over one of you self-appointed sleuths?

As others have said Shimano are almost certainly not going to give me anything in any case, never mind admit any liability. At best this might, just might, be another data point for their engineers to bear in mind when re-designing these things.

I know one is not supposed to feed the trolls, but I just don't understand some of the behaviours exhibited on here. Again, thanks to those of you who have engaged constructively here.

The small piece on the right. I'm curious as to whether there are any impact marks on the outside.

milemuncher1

It looks like an impact caused the problem to me, whether the O.P. was aware it had even happened, is the question.