Shimano 9000 Crankarm Failure.

[dvs cycles]

Thought I had a bent pedal when my right foot would twist down at the 5 o'clock and up at the 11 o'clock positions. Changed pedal but same result.
Checked closer and found a crack just in from the pedal mount on the inside about an inch from the pedal all the way across.
Could have been serious.
Anyone else know of this failure?

[cinema]

inherent design flaw in the generation https://www.instagram.com/thanksshimano/

[Robot870]

Crap! I bought a set a few months ago.....Glad your ok

[AngryScientist]

yea, shimano hollow cranks are mostly reliable, but failures do happen, as per that insta account!

i've gotten into the habit of looking over mine pretty closely every couple weeks . hopefully i'd catch a failure before it happens.

[zzy]

Honestly the number of failures of first gen 11sp cranks is almost getting into class action territory.

[reuben]

Dang! Glad you noticed it before a chatastropbic failure.

Anyone know.if the current generation fixed that?

[thirdgenbird]

Originally Posted by reuben

Dang! Glad you noticed it before a chatastropbic failure.

Anyone know.if the current generation fixed that?

There are examples of current ultegra and dura ace cranks in the provided link.

[reuben]

Originally Posted by thirdgenbird

There are examples of current ultegra and dura ace cranks in the provided link.

Yeah, I saw that. Are they all the same generation? Are any of them the current generation? Or has the issue been fixed?

[stev0]

I think as far as anyone can tell all the new crankarms are susceptible to the same failure mode.

[pbarry]

Originally Posted by reuben

Yeah, I saw that. Are they all the same generation? Are any of them the current generation? Or has the issue been fixed?

If you look at the images and scroll down, there are 9000, 9100, R8000, 6800, 5800, etc. So, yes, current and previous generations of hollow crank arms.

[Matthew]

Great. Got a NOS 6800 group on my Moots. I broke a 7800 arm in the same spot 4-5 years ago.

[buddybikes]

Inherent nature of manufacturing and push to go lighter and lighter. Shimano is far from the only ones.

[Peter P.]

Originally Posted by steveandbarb1

Inherent nature of manufacturing and push to go lighter and lighter.

How true. The consuming public got what they wanted...

[mcteague]

Originally Posted by Peter P.

How true. The consuming public got what they wanted...

I had an Avocet crank snap at the pedal hole back in the 80s. Solid aluminum. My 11s carbon Chorus crank had the threaded pedal insert come loose. Things break. When you see lots break in the same way then maybe there is an issue. Otherwise....

Tim

[oldpotatoe]

[QUOTE=steveandbarb1;2751430]Inherent nature of manufacturing and push to go lighter and lighter. Shimano is far from the only ones.


Gee, only 12 posts before a "how about Campag"??...

Yup, many break but not due to design flaw, as hollow arm, shimano, welded together(bonded) seem to be.

Honestly the number of failures of first gen 11sp cranks is almost getting into class action territory.