Ultegra Road triple crank cracks due to fatigue.

Jay Beattie wrote:
jim beam wrote:

snip

my shoes are size 13, and i /never/ "polish" the crank. ever. in fact,
i find it hard to understand how it's possible if cleats are positioned
correctly.

It's easy -- size 13 mountain bike shoes and neoprene or rubberized
fabric (Sugoi) booties for four (or more) months of the year. They add
a lot of bulk. I also have mobile ankles. By the way, I put probably
40K on an '80s Dura Ace crank which was beaten and polished, and it
never broke. I thought the Japanese cranks were pretty tough until I
broke the Ultegra triple. I am a little suspicious of the hollow
technology. -- Jay Beattie.

if fatigue was nucleating from inside, i'd say sure, but with the case
we see here, there is no difference compared to the failure you'd see in
a solid section. i therefore have no fear of hollowtech cranks.
indeed, i love their stiffness.

wrote:
Anyone seen this happen? I never have before and I'm cycling all my
life. I've had bottom bracket axles crack in the past

http://technology.open.ac.uk/materials/mem/mem_ccf.htm

I like the crank pics because I've read the "Campy cranks never
actually break where they all crack". Plus, this one looks like it
really tried not to come apart g.

People used to file the sharp edge off at the spider/crankarm junction.
--D-y