Broken/Sheared Cassette

[clydesmcdale]

So this happened last night.... no idea why. Anyone else experience this?











Was coming up a short sharp climb and then heard a clank. Assumed at first, I’d either dropped a chain or broke a spoke. Stopped dead as I lost any resistance at the pedals. The guy behind me coming up the hill stopped, bent down and picked up part of my 16T ring which had spat out. Looked down at the cassette and saw half the 16T ring missing and the other half sitting up a touch.

It’s a Campagnolo Chorus 11 speed Cassette 12-29. Had it since September 2012. Always been on my carbon clinchers. Probably done a little over 1500km. Always kept reasonably clean. Last time I had the cassette off was about a 2 months ago and I always torque to spec when putting it back on.

Bought from Ribble, so have just contacted them requesting refund or replacement. Not sure how I’ll go here for a decent turn around. Would like to get it sorted ASAP, but expecting it to drag on with multiple queries and proof of damage, with arguments from them telling me it’s my own fault for some reason.

[biker jk]

I can quite see in your photos but does the 16T cog have a carbon fibre carrier? It would be more likely to break in that case if a lateral force was applied due to a inadequate tightening of the lockring or perhaps play in the hub bearings?

[jacks1071]

If the lockring became loose which would only happen if it wasn't done up to spec I'd imagine that damage could be possible.

Otherwise it looks like a warranty fault, I can't think of what you could do to break it otherwise.

[human909]

Too much TORQUE!

I've done similar to my middle chain ring once, bent it sideways. Simply put the stuff is engineered with little leeway due to the desire for weight savings.

[clydesmcdale]

I can quite see in your photos but does the 16T cog have a carbon fibre carrier? It would be more likely to break in that case if a lateral force was applied due to a inadequate tightening of the lockring or perhaps play in the hub bearings?

Lockring tightness was certainly one of my first thoughts when I got it home and had a look. However I was thinking too tight. But as can be seen the spacers are still there and in tact.



If they had broken/split and/or came away I would expect to see some lateral movement. Certainly hadn't felt any movement in the hundreds of kms since last I reinstalled the cassette.

I was putting alot of pressure on the pedals grinding pretty hard up a bit of a wall and thrwing it side to side. So maybe some flex??
I dunno, just hoping to get it sorted pretty quickly. LBS quoted $250+ for replacement they didn't have in stock, where it's around $100 online.

[clydesmcdale]

Too much TORQUE!

I've done similar to my middle chain ring once, bent it sideways. Simply put the stuff is engineered with little leeway due to the desire for weight savings.

Didn't see this earlier... Surely not?

I would have expected the gear should be able to put up with an average rider putting a bit of pressure down. What happens when the pros wail down in sprints?

[jacks1071]

I can quite see in your photos but does the 16T cog have a carbon fibre carrier? It would be more likely to break in that case if a lateral force was applied due to a inadequate tightening of the lockring or perhaps play in the hub bearings?

Lockring tightness was certainly one of my first thoughts when I got it home and had a look. However I was thinking too tight. But as can be seen the spacers are still there and in tact.

How could you think it was too tight? Your origional post says it was torqued correctly.

You either installed it with a torque wrench or you didn't.

[clydesmcdale]

I can quite see in your photos but does the 16T cog have a carbon fibre carrier? It would be more likely to break in that case if a lateral force was applied due to a inadequate tightening of the lockring or perhaps play in the hub bearings?

Lockring tightness was certainly one of my first thoughts when I got it home and had a look. However I was thinking too tight. But as can be seen the spacers are still there and in tact.

How could you think it was too tight? Your origional post says it was torqued correctly.

You either installed it with a torque wrench or you didn't.

Hence as to why I dismissed this first thought.

[Wal42]

Where it is broken, can you see any signs of discolouration of the metal?

I've not had anything to do with late model Campy, but it appears that the ring has stress fractured, it would be unusual for it so suddenly fail in such a catastrophic way (but then rings are very thin & they now feature lots of weight saving holes, etc), without first cracking, you should see a discolouration where the ring cracked before failing. It could very well be a flaw during manufacture (but don't quote me on that), if it was then probably (warranty conditions vary between manufacturers & more importantly distributors) subject to warranty replacement, if it was in the motor vehicle industry the company would record that in case of further similar events occurring, then they would do a 'field service' (warranty repair/replace), possibly a large company like Campy would do likewise.

I'd take it to your LBS & have them contact the Campy rep & ask questions about why & whether it is a warranty repair.

[clydesmcdale]

Where it is broken, can you see any signs of discolouration of the metal?

I've not had anything to do with late model Campy, but it appears that the ring has stress fractured, it would be unusual for it so suddenly fail in such a catastrophic way (but then rings are very thin & they now feature lots of weight saving holes, etc), without first cracking, you should see a discolouration where the ring cracked before failing. It could very well be a flaw during manufacture (but don't quote me on that), if it was then probably (warranty conditions vary between manufacturers & more importantly distributors) subject to warranty replacement, if it was in the motor vehicle industry the company would record that in case of further similar events occurring, then they would do a 'field service' (warranty repair/replace), possibly a large company like Campy would do likewise.

I'd take it to your LBS & have them contact the Campy rep & ask questions about why & whether it is a warranty repair.

Having just had a quick look, can't see any discolouration. Certainly hadn't noticed any cracking prior to the failure when I gave it a quick clean whilst still on the wheel on Friday of last week. It's failed right at the points of the weight saving penetrations as can be seen in these photos.



I've had a generic response from Ribble this morning and will be sending it back for their inspection. They said to include reciept for postage, which they'll reimburse if it's a warranty. Looks as though they're quoting a turnaround of 10-14 days once they've recieved it.

I was in the LBS yesterday and showed them what happened. Whilst they were interested enough to comment they'd never seen this before, they didn't offer any suggestion as to why and I wasn't looking to extract info out of them considering I didn't purchase it from them.

[sogood]

Manufacturing/material problems invariably happen and you've probably won the 1:1,000,000 prize. Go and buy a Lotto and wait for your replacement cassette.

[DavidL]

Manufacturing/material problems invariably happen and you've probably won the 1:1,000,000 prize. Go and buy a Lotto and wait for your replacement cassette.

+1

Happened on a 10sp Shimano cassette up here a month or so back. Can be a long ride home if you can only use the for big cogs and your out in the country side.

Without providing photos of your legs, I would say this is just a manufacturing defect. See how you go with warranty, they are not cheap cassettes.

- David.

[15wilsonwu]

Are you riding a FM098?

[clydesmcdale]

Are you riding a FM098?

yep

[15wilsonwu]

Are you riding a FM098?

yep

Ah, I reconize the seatstay cause I just got a FM098.
Sorry for the fact I have nothing to contribute to the oringinal topic, lol.