View Single Post
Old 02-18-2011, 01:53 PM   #9 (permalink)
UFO
Master EcoModder
 
UFO's Avatar
 
Join Date: Sep 2010
Location: Denver, CO
Posts: 1,300

Colorado - '17 Chevrolet Colorado 4x4 LT
90 day: 23.07 mpg (US)
Thanks: 315
Thanked 179 Times in 138 Posts
Quote:
Originally Posted by jamesqf View Post
Depends on how thick the metal & rubber are. I don't have numbers, but it seems possible that a larger, lightweight rim could weigh less/have lower rotational inertia that a smaller rim with a heavy tire.

Also, as the OP said, if the tire diameter is larger, it could effectively lower the gearing, which could be an advantage if he does a lot of highway cruising.

Then there's the question of tread width: wider tread means higher rolling resistance.
Invariably the metal in the wheel is heavier than tire sidewalls. And if the tires fit a larger wheel size, the tire sidewalls are even heavier. A smaller wheel with the same diameter tire will almost universally be lighter than a larger wheel, let alone the lower rotational inertia.
__________________
I'm not coasting, I'm shifting slowly.
  Reply With Quote