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Here's an important question: where does rolling resistance come from?
I think the contact patch in and of itself is irrelevant. An incompressible, perfectly smooth wheel rotating on a frictionless bearing rolling over an incompressible, perfectly smooth surface should see no friction (as long as it is not slipping)...whether that wheel is 1 foot wide or 1 mile wide.
As far as the tire is concerned, rolling resistance comes from flexing of the wheel. While the tread compresses, the majority of the flexing comes from the sidewall. Higher pressure doesn't work primarily by decreasing the contact patch, it works by decreasing sidewall flexure. Unlike balloons, radial tires have metal belts running under the tread, limiting their shape anyways.
Now, why would a skinny tire be more beneficial then a wider tire? Less flexing and surface area for slipping, but specifically how?
I think increasing wheel weight to aid in cruising is a bad idea. It's akin to putting extra weight in your car to tackle hills. Sure you will glide longer, but you'll take more energy to get up to speed in the first place. Unfortunately, the 2nd Law of Thermodynamics rules...you'll always get less energy out of a glide then you put into the acceleration. When everything is appropriately sized, light weight maximizes efficiciency.
Increasing wheel diameter may also be helpful by lowering engine rpms. Generally a useful feature, but must be appropriately sized.
Intuitively, I'd choose a wheel first based on weight, then diameter, then width.
- LostCause
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