Look equipment failure



CAMPYBOB

Well-Known Member
Sep 12, 2005
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STEEL! Because it's REAL!
ccf12_1.jpg



Multiple steel dropout failures:

http://pardo.net/bike/pic/fail-001/FAIL-063.html
 

Yojimbo_

Well-Known Member
Apr 17, 2005
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Hello Again Everyone

OP here again - I haven't checked in for awhile. Interesting discussion going on.

A couple of requests I see about what actually failed. I thought I had made that clear by saying it was the steerer tube but perhaps not. To further elaborate, my Look bicycle has aluminum bars and a CF frame. There's a part that connects the bars to the steerer tube - I forget what it's called. It's the part that can be replaced if you want more or less reach.

See photo below.

I've now replaced the bike with the Cervelo I mentioned earlier. The Cervelo has a different design for this part - there's a piece of metal inside the tube at the point of connection where the failure occurred. This would strengthen the component.

Finally, if manufactures make products that are subject to fatigue failure, they should also give us an expected lifetime of their products so someone doesn't unknowingly exceed the fatigue limits.

20171102_194418.jpg
 

dhk2

Well-Known Member
Aug 8, 2006
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Believe the part you're referring to is the stem. Anyway, thanks for the photo which clears things up.

Some of the manufacturers are clear that their equipment can fatigue and fail, and that these failures are considered normal and not covered by the warranty. I've seen a couple of owner's manuals that mention this, and advice the rider to stop riding and have the bike inspected immediately if any movement, looseness or creaking noise is detected. It's really up to the rider then to inspect and monitor his own equipment.

Setting an "expected life" seems like a good idea, but anything they put out would have to be wildly conservative due to the wide differences in loads and stresses each individual puts on their equipment. If they told us to replace the frame or fork at a fixed interval of time or mileage to preclude fatigue failures, I doubt few would do that anyway. A better plan would be to make sure the part is designed so that any fatigue crack can be detected in plenty of time before failure. And then to educate the users as to their responsibility to inspect and monitor before any total failure occurs.

Anyway, hope you have a much better experience with the Cervelo and that you ride it in good health for a long time!