Tires. Skinny/wide? Tall/low pro?

[oldtamiyaphile]

Originally Posted by Ni87

Thanks again for all the input. My question is why doesn't having a low profile tire help with economy? Like someone said the trains have steel wheels for efficiency and we have air more for the cushy ride. Wouldn't the lower profile make for a harder more effienct tire?

Super hard/ high pressure works on steel rail road track or on bicycle velodromes only. On a rough surface (even the smoothest road counts as 'rough') lowest RR comes from having the right amount of compliance to the surface.

[Ni87]

On my xterra when I first had 265-75r15 I could only get 15-18 mpg on some bald bridge stones. Then I found a set of a little less bald 265-60r18 Goodyear assurance tires. I think they have eco focus so the test isn't really fair but with that I got 18-22 mpg. My worst is my winter tires. But also with winter tires you get really cold starts and lots of snow. But even on the highway I get 10-15 mpg. Those are 275-65r16 (I think) yokohama iceguards. Does anyone have some more examples of tire sizes and how it improved economy?