Although the following question could be answered by the maintenance forum, I'd like a response from those of you who ride long distances based upon your experience.
When you encounter a puncture, you have the option of patching the tube or replacing it.
However, when your tire is worn out (i.e., no or little tread left) do you replace the tube as well as the tire?
Do tubes wear out?
I ask the question because in the wheelchair shop where I work, we replace both tire and tube because we were told the tube may have rubbed thin by the time the tire is worn out. Sometimes you see the valve stem at an awkward angle which seems to indicate that the tube has moved within the tire. But if the tube has not obviously moved (i.e., the valve stem is still perpendicular to the rim), has the tube suffered wear nonetheless?