Originally Posted by
rydabent
Look at it this way. Most everything that combines function ends up being a compromise of both functions. A rim that needs a brake surface is not as strong or aero, or as light as a rim that goes on a disc brake bike.
Separating the functions means the rim will never be worn out, and a worn disc is many times cheaper than a new rim with a rebuild of the wheel.
Yea, but in my experience, a wheel is pretty much done (spokes, hub, etc.) by the time the rim wears out. I've bought many new wheels, but never because the rim wore out.