[mwebb]

the tall skinny tires do not have lower rolling resistance than tall fat tires
because
the patch (area of tire that contacts the road )size remains the same so the skinny tire must deflect the sidewall more as the tire rolls , which causes more heat and
higher resistance to rolling

a ten speed bike tire will have the same "patch" size as your car's tires when loaded to the same value ,the bike tire would fail very quickly , the comparison is not valid

your basic theory is incorrect , listen to what the others have said
making this switch would cost me around $425.

worth it?

anyone know what kind of mpg gain the decreased rolling resistance would equal?

right now I have no idea if it's 1% or its 20% or so I'm having trouble deciding if I should go for it.

can anyone shed any light on this?


(I do know that 10 speed bike tires are really low rolling resistance, so the smaller your footprint is the better your mpg's should be but I have trouble calculating what the gain would be for this car tire project, I welcome all feedback)

[QUOTE=mans;276425]

Originally Posted by Ryland

You don't say what kind of car you have or even your full tire size



the full size of the tires I was LOOKING TO ACQUIRE is 125/15 there is NO middle number for these old tires. see link Firestone F560 - 125R15

if there was a middle digit it would be like 125/150/R15 cuz the sidewalls are so tall while the width is so small!
see again here up close: Firestone F560 - 125R15