Tire size
 

We all know that taller tires give you a taller gear, but make you less aero. And shorter tires lower the vehicle making it more aero, and take less energy to get them up to speed (weight etc being equal). Would it then make the most sense to use shorter tires on a vehicle used mostly in city driving and taller tires for a vehicle that is used mostly on the highway?:confused:

It's odd what you ponder when you can't sleep, isn't it?

I would think that even in town taller would be better for the change in gear ratios.

maybe someone needs to do some A-B-A testing.

There is no cookie-cutter answer to that. There are many factors (including frontal area - the higher ride height is worse) than just overall gear ratio. Having a LRR tire is more critical than minor variations in tire diameter, all else being equal.