Originally Posted by
robtee92
The big giant point is that for months on the first set of ancient decaying gumwall tires, and weeks later on some brand new gumwall tires I was able to inflate it to 110psi with no problems, and now I'm not. This leads me to believe there's something wrong with the tire...
Not wrong, but different. Your new tires, like pretty much any new tires made today, are designed with hooked rims in mind. Sure, they'll work on straight-sided rims, but maybe not reliably at high pressures. Your old tires were probably designed for straight-sided rims. There may be something subtly different about their bead design that helps 'em hold to the straight-sided rim a bit better.