OMG, you must be joking?!!!!
It's no surprise that you chime in to sound like a genius, to teach us all something. But wow, you underestimate the intelligence of others. I don't have a degree in any of this, but like so many others, I actually do know plenty about the basic physics involved. Even if a guy doesn't know the terms or formulas involved, he can still "get" how it works.
It's really damn simple, believe it or not. This is all basic fundamentals to anyone with much experience in some form of racing, for example. Or anyone who has mechanical inclination. Or played with tops as a kid. I think I used somewhere here is rollout.(if not, I was thinking it, which you already knew of course), which is a term in racing that refers to the effective total gear ratio that takes into account the tires also, measured in revolutions of the engine/drive train relative to the actual distance traveled. No pi calculations needed, professor... because that's already built in to the "rollout" figure. You do NOT have to be an engineer or have a degree to understand the basics involved here. Any "uneducated" motor head can figure gear ratios and rollout, and won't talk down to others as if it's beyond them. You tried so hard to sound like an expert this time, explaining really simple things as if it was complicated, it makes me think you actually don't get half what you are saying????
Seriously, why the need to step in and "educate" especially when it appears maybe you don't really understand it? BTW, tires of the same diameter and width, but different rim size (17 vs 19), will have a difference in rotational inertia... but main difference is in the rim, not the tire. The larger rim has more mass at the perimeter, so it's heavier and the center of mass is farther out. It's not the tire. It's pretty simple, if you take away the big words and arrogance.
But that 3.14 thing... yeah that's pretty advanced stuff there. Gee thanks, it's been a while since I was in 5th grade. Show of hands, how many here didn't know how to figure the circumference of a circle? anyone?