Galled Bearing Cones Puzzle - Shimano FH-M510 Hub ??? - Page 3

Carl Fogel writes:

>> Dianne Feinstein writes:

>>>> I've seen spalled cones, but never the cups. Are the cups made tougher because they're more
>>>> expensive to replace, or is it because they're loaded differently, or have I just been lucky?

>>> I'm just guessing here, but the fact that the cone is stationary may mean it is loaded always at
>>> teh same area: the bottom.

>>> The cup, on the other hand, gets loaded round and round, so the fatigue is spread out over a
>>> larger area.

>> I see, you never take wheels out of your bicycle or at least mark the axles so you can reinstall
>> them oriented for shortest life.

>> Good thinking!

> If I lived in a place where goathead thorns didn't force me to fix flats and if I wasn't bad at
> maintaining wheels that I have to replace a drive-side spoke every month or two, I suspect that my
> wheels would rust into place on the frame.

> Dianne's suggestion about the cones facing asymmetric stress for long periods seems rather
> sensible, whatever the actual effect may be.

Well there are other reasons for taking wheels out of a bicycle such as tossing them in the back of
a car to ride somewhere else than right around home. With the variety of great rides in California
all year around, driving to a starting point a hundred miles away is not unusual. Even 20 miles to
cross the freeway infested Santa Clara valley is a common event. Mt. Hamilton to Livermore and back
loop being a classic 100 miler in this region.

http://mthamilton.ucolick.org/hamcam/

> I'm just jealous that she thought of it. Aren't you?

I have considered it but my cones usually spall at least 3/4 of their circumference when they go
anyway, and as I said, my wheels come out pretty often. That's why I thought of the scenario I
mentioned above.

Jobst Brandt jobst.brandt@stanfordalumni.org