Quote:
Originally Posted by jamesqf
Just a thought: Why is it that the skinny tires on my road bike, with sidewalls not much thicker than a stiff sheet of paper, can take - no, require - 100 PSI or more, but the much thicker sidewalls of car tires can't (in some people's opinion, at least) take more than 32 PSI?
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Read my post, the less weight the higher you can inflate to. (or if you lower speed) Though one has more effect than another.
Its all about how much stress you put on a tire, something 700lbs (or less) pushing on a tire can exert less compression and forces than something 4000lbs.
Also the way your tires are loaded a severe bump displaces less air compared to the area inside the tire resulting in less of a pressure spike. (big diameter small area tires load differently than wide fat smaller diameter tires)
Also ALL new tires can be inflated to about 60psi but it does affect their wear profile along with weight and speed ratings. I guess it depends on what costs more fuel or tires? In my case I go through tires quickly do to the wonderfull roads around here (all sidewall slices) so I tend to overinflate, I have tried following the guidelines and overinflating and it seems my overinflated super cheapo off brands last longer than namebrand tires. I still can't figure it out, must just be luck (or lack therof) that abused tires are lasting longer. (I rarely overinflate past 50psi, except on tires that state 60psi on the sidewall, usually between 40-50 is optimal for me)
Also there are types nylon inner layers that can be employed in tires to virtually eliminate blowouts and increase max pressure but they are rarely employed, ride and handling are generally considered more important than rolling resistance. Similar trick would be to have a unburstable nylon/teflon/etc inner tube that doesn't expand much, would have the same effect.
Cheers