[Fignon's ghost]

Hello.

I’m surprisingly proud of this cycling achievement. Was out the weekend and took a short, sharp, steep hill with a fast climb. To my astonishment, I’ve managed to tear my Ultegra 6800 (53) crank arm away from the chainset. There’s a great big tear in the aluminium casing from the base of the arm across the first fixing. Which has warped the arm and rendered the set useless.
So…
Can anyone shed light on how common an occurrence this is ? In my 30 years of road cycling. I’ve never managed to get anywhere close to this achievement.
Normally, I’d be miffed at the extra cost to replace the set but given the held opinion that these cranksets are meant to be infallible. I wear it as a badge of honour.

Any thoughts welcome.

Topic

[Anonymous]

Spécialités TA still do the

Spécialités TA still do the classic Pro 5 vis:

https://specialites-ta.com/130-pro-5-vis

Well, from time to time anyway. But might be worth waiting for. And looks better on a slender steel frame.

[ChrisB200SX]

Fignon’s ghost wrote:

Fignon’s ghost wrote:

Davey. Thanks for deflating my balloon! FWIW. I did it on 172.5. My other is a 105. As Chris pointed out. There are two sections to the ultegra 6800 composition. Compared with the 105, which looks a solid, single cast unit. Presumably it’s slightly heavier. 105 is good enough for me.

I’m not sure 5800 is actually any different in the 6800’s general construction, maybe they used a different/thinner alloy or different adhesive for Ultegra? I’ve got two 5800 and one R8000. I’m hoping the latter is less prone to the earlier Ultegra crank death.

[wtjs]

Ultegra Pasta Cranks- a true

Ultegra Pasta Cranks- a true saga of our times

[hawkinspeter]

I reckon it’s fairly common
I reckon it’s fairly common

https://road.cc/content/tech-news/shimano-claims-no-design-problem-hollowtech-cranks-287827

https://road.cc/content/forum/psa-sometimes-creak-needs-be-investigated-287149

[Welsh boy]

“a short, sharp, steep hill”.

“a short, sharp, steep hill”.  Not Caerfilthy mountain getting ready for the ToB by any chance?  What length cranks do you ride?  A pair of 165mm Ultegra and/or 170mm Tiagra chainsets in Newport going for a very resonable price if you are interested.

[Fignon's ghost]

Davey. Thanks for deflating
Davey. Thanks for deflating my balloon! FWIW. I did it on 172.5.

My other is a 105. As Chris pointed out. There are two sections to the ultegra 6800 composition. Compared with the 105, which looks a solid, single cast unit. Presumably it’s slightly heavier. 105 is good enough for me.

[Daveyraveygravey]

Fignon’s ghost wrote:

Fignon’s ghost wrote:

Here we go…

  Looks very typical to me!  I’ve got through two in 8 years, usually around 4 years of use.  There’s a website on Instagram called “thankshimano” which has loads.

I managed to get a warranty replacement the first time, but it took a lot of nasty threatening letters & emails.  I’ve now switched to 105 cranks in the hope they last longer.

[Fignon's ghost]

Thanks Chris.
Thanks Chris.

Yes. The tear begins at the earliest torque point.
It’s not as if I use this one all the time. I have two regular road bikes. Doing anything from 50 to 300 miles a week between them.

I’ll probably go for the r7000 instead. I’m a hobby rider but, even though I say it myself, have legs like Abdoujaparov!

[ChrisB200SX]

This looks a little different

This looks a little different to the usual Ultegra failure, which tends to be the debonding of the arm section. Maybe debonding at one edge has caused a weak point there which has resulted in a crack that has now spread?

Does appear like you’ve mangled it with huge torque though, chapeau!

[Fignon's ghost]

Here we go…
Here we go…

[Author]

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