I have never worn out a rim from braking. Many pads though have been replaced.
The art & science of material engineering dictates composite brake pads must abrade slowly, distributing the heat of friction through particle disintegration. Even with bi-metallic pads, the hardness of the rim is superior to that of which is designed with foresight to wither and wear away. The only factor that can change the metric is flying debris; the dust and dirt and mud of the good old earth to act like the fine powder of Jeweler’s rouge – and even then only polishes the metal surface and glazes the pads – causing them to squeal, or… prematurely wear.
Such is the fate of pads by overt design to perish into dust and oblivion by force of action through rent of our joy to travel headlong into the fury of life profound in a flailing attempt to reduce our progress. And by similar purpose, for the rim to withstand the forces that conspire to collapse the calliope providing the sturdy support to wheels in motion.
I could scarcely imagine the opposite… although with enough coffee
One of two principle object materials must change: Either the pads themselves become harder, or the rim material becomes weaker.
With automobiles (and most likely many other applications) we have an option to purchase brake materials of varying hardness. High-Temp brakes for instance are typically very hard and loaded with materials commonly associated with refractory bricks and able to withstand tremendous heat. When amalgamations of this sort are employed, the pads are more durable – yet also more brittle, and definitely erode the disc, drum, or rotor. However we must also consider that all of these surfaces are conveniently serviceable or replaceable, and their best use is with heavy duty or racing applications where costs of maintenance are factored in the balance. Therefore, under normal conditions
- hard brake pads on a bicycle rim would appear out of character with the function.
If we entertain however briefly that rims are softer, I fear the wheel might deform more easily or collapse without the necessary surface-hardening treatment to assuage ductility, to enhance elasticity, and to anneal the façades against unbridled friction. Such a condition would not be practical, nor would it be marketable for very long: Encountering such a rim would be noticeable.
That said, I have scored many rims by lack of attention. A diligent person would be wise to repair the situation as soon as possible. Once I lent my MtB to my former
GF; notice that I put the emphasis on former
. My fault; I forgot the Rule: Never lend your bike out to anyone.
Every mud puppy deserves a good bath.
PS – I too migrated to disc brakes to eliminate the majority of issues associated with messy rim brakes; I cain’t stands the squealing. Though now I have to tolerate singing rotors. No free lunch <sigh>