Quote Originally Posted by plantluvver
The new tire (rear) says to inflate to 90 PSI and the old one to 100PSI. Because of my weight (260 lbs.), I would like to keep the pressure as high as possible, would it be okay to overinflate the new tire by 10 PSI? I am wondering if I should buy a tire with a higher pressure rating.

Another question is whether this tire could be used on my other bike's rim. The rim size is 27 x 1 1/8, versus 27 x 1 1/4.

I noticed one other thing that seemed alarming at first, but it may not be such a problem as I first thought.
I noticed that when I turned the axle in the wheel, one side of it was bent. The side with the gears. This scared me, because I thought my wheel was wobbling around. Then I realized that the axle actually remains fixed. So it might not be a serious problem.

Mary
(1) Don't inflate over the stated rating on the tire. It may blow off the rim if you do. I wouldn't invest in a new tire just to get a higher pressure rating unless the 90 lb tires keep failing on you.

(2) You can probably get away with a 27 x 1 1/4 tire on a 27 x 1 1/8 rim. Measure the rim widths of your 2 bikes to see if they are really different. They may not be. In any case, you can try it and see if it work.

(3) A bent axle should be replaced. Bent axles are pretty common on bikes of that vintage (bolt on axle, not quick release, right?) That's one reason that freewheeled hubs were replaced with freehubs/cassettes, to put the hub bearing closer to the bike frame on the freewheel side. A bent axle will put excess wear on your hub bearings and misalign the chain and freewheel. It shouldn't cause catastrophic failure but it should be fixed. Ask your LBS if they can get the part, or try www.loosescrews.com. To do the replacement yourself, you'd need a freewheel puller and cone wrenches.