Originally Posted by
Andrew R Stewart
I think what Racing Dan is talking about is when there's excessive (and there's that qualifier once again. Our passion is full of judgments and opinions) bearing preload the rolling surfaces go through a work hardening process as they are indented and rebound under the pressure of the balls. I think of it like a too heavy truck for the road's surface. The layers of road will flex and then in time crack.
Not every situation has had scientific research and a published paper. But the decades of hands on findings do speak just the same. Andy
...ball bearings and how they work have been thoroughly researched. Cone and race surfaces are case hardened, at the very least, in a quality bearing assembly. I honestly do not see how what you have described can occur.
Certainly excessive bearing load (to the point where the wheel no longer spins freely under the weight of the valve stem) ought to be avoided. But like @
davidad, Mr Brandt, and a lot of other people I have preloaded both headset and wheel bearings on bicycles for many years now, with no noticeable ill effects.
But I'm a test subject group of one, which is why I asked for a source.