FAILURE Shimano Cranksets

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NickJHP
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by NickJHP

There was a long thread about Shimano crank failures on the Bikeradar forum last year: https://www.bikeradar.com/forums/viewto ... nk+failure.

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TonyM
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by TonyM

One bad batch of Ultegra cranksets indeed.

Something really unusual for Shimano...that shows how good their products are...

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pdlpsher1
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by pdlpsher1

Shimano makes a LOT of cranks. So the failures in terms of percentage is probably still very small.


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ak47
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by ak47

Indeed. They probably make 10000x the number of THM cranks. The rate of failures is probably the lowest amongst all crank makers out there.

Jugi
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by Jugi

kgt wrote: BTW I could never understand why Shimano insists on alu cranks. Are these much cheaper to produce? A carbon crankset is better in many aspects including strength.
Bikerumor had a big article on this subject three weeks after you posted that message. The information is basically marketing fluff, but it's well written.
Kayrehn wrote:I wonder if anyone seen broken sram or campagnolo carbon cranks before? Don't want to derail this thread but just really curious to make some comparisons...
I bet SRAM and Campa break down as well, but I quess at least for carbon cranks a pedal thread separating from the crank (or a similar issue at the spindle's end) is the most common issue. And for those, it's usually hard to rule out all types of user errors.
Last edited by Jugi on Sun Aug 05, 2018 4:26 pm, edited 1 time in total.

Lancesleftnut
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by Lancesleftnut

Happened to me yesterday. Awaiting to see what my local dealer might be able to do as it has happened just outside the 2 year shimano warranty period.
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sychen
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by sychen


Lancesleftnut wrote:Happened to me yesterday. Awaiting to see what my local dealer might be able to do as it has happened just outside the 2 year shimano warranty period.
Whoa that's scary.. The top and bottom halves looks to be held together by glue only. Only the pedal bolt held the end bit as it snapped off.

All the shearing force over the 2 years just worked the glue loose.

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Alexandrumarian
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by Alexandrumarian

Imagine this happening in a sprint and getting your leg impaled....

XCProMD
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by XCProMD

If this would happen to any maker other than Shimano they would be in the tits.

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Kayrehn
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by Kayrehn

XCProMD wrote:If this would happen to any maker other than Shimano they would be in the tits.
^ it seems as if the general reaction is simply a shrug with the reasoning that 'everything can break'. I've heard people dissing etap enthusiastically because they shift a micro-second slower, but the calm over numerous breakage of shimano cranks is amazing.

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Discodan
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by Discodan

Kayrehn wrote:
XCProMD wrote:If this would happen to any maker other than Shimano they would be in the tits.
^ it seems as if the general reaction is simply a shrug with the reasoning that 'everything can break'. I've heard people dissing etap enthusiastically because they shift a micro-second slower, but the calm over numerous breakage of shimano cranks is amazing.

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The response I was seeing wasn’t “things can break” but “as a percentage of cranks that Shimano ship, this is most likely a tiny fraction”. On the other hand, 100% of eTap ship with the slower shifting


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Rippin
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by Rippin

Discodan wrote:
Tue Aug 07, 2018 9:42 am
The response I was seeing wasn’t “things can break” but “as a percentage of cranks that Shimano ship, this is most likely a tiny fraction”. On the other hand, 100% of eTap ship with the slower shifting
Even if the percentage is small, a failure in the crankset can cause injury. Slightly slower Etap shifting won't. :wink:
Last edited by Rippin on Tue Aug 07, 2018 5:47 pm, edited 1 time in total.
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spdntrxi
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by spdntrxi

Rippin wrote:
Tue Aug 07, 2018 5:39 pm
Discodan wrote:
Tue Aug 07, 2018 9:42 am
The response I was seeing wasn’t “things can break” but “as a percentage of cranks that Shimano ship, this is most likely a tiny fraction”. On the other hand, 100% of eTap ship with the slower shifting
Even if the perscntage is small, a failure in the crankset can cause injury. Slightly slower Etap shifting won't. :wink:
I'm sure SRAM cranks can break too... I've broken a non drive side THM M3... yeah it was damn scary because I was hammering up a hill at the time, good thing it was early in the group ride and I just one-leg pedal'd back home.
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XCProMD
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by XCProMD

Everything can break. But I have yet to see a SRAM crank failing like this, without having ever heavily impacted on anything. Even SRAM carbon Mtb cranks are proving tough.

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Cemicar
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by Cemicar

A carbon crank wouldn't fail like this though...

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