02-15-2009, 10:16 PM
Are there any good hints on how to properly size a tire for a rim? I figured out pretty quickly that you need to match the inner tube to the tire in terms of size (26"x1.75 for tire and tube both). But for the rim, I ran across something curious. One of my bikes had 26"x1.95 tires and tubes on a 26"x1.50 rim.
Now my question is this: What made it so that particular combination works and the 1.75 tires and tubes I tried to replace one of them with (and failed) not work? I noticed the 1.95 tires were pretty flexible and more balloon-like than the 1.75 tires (which are kevlar-lined street thread from what I can tell - man them were fast when I got them on my other bike with 1.75 rims), so that is probably what made them work on the 1.50.
Maybe more to the point: How do I know what should work on a rim and what shouldn't? I looked at two or three sites (including the Sheldon Brown one) and still didn't come away with a good explanation for the above.
Now my question is this: What made it so that particular combination works and the 1.75 tires and tubes I tried to replace one of them with (and failed) not work? I noticed the 1.95 tires were pretty flexible and more balloon-like than the 1.75 tires (which are kevlar-lined street thread from what I can tell - man them were fast when I got them on my other bike with 1.75 rims), so that is probably what made them work on the 1.50.
Maybe more to the point: How do I know what should work on a rim and what shouldn't? I looked at two or three sites (including the Sheldon Brown one) and still didn't come away with a good explanation for the above.
Why is it that they make adult bikes that'll generally work for 5'9" or above, yet when you pedal these same bikes they only work for someone who is 5'4" or so?
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