6" tires, both axles?

[Duuuuuuuude]

RPM = measurment of speed, you are incorrect sir. If the inside of the record were spinning at a faster speed it would horribly warp the record :ror:

RPM is a measurement of time and distance, not a measurement of speed, though using time and distance you can derive speed. Meaning that if you know how long it takes an object to travel a predetermined distance, you can determine the speed at which it is traveling.

An object moving in a 1" circle once every second will do it at a slower speed than an object moving in a 6" circle once every second. Same rpm, different speeds.

 

[C*H*U*D]

That was what I was trying to explain when I said about one going faster, but it looks like I confused the speed, really thought the smaller would spin faster,

Your terminology is what's throwing you off. Both tires will "spin" at the same RPM...this will not change. At the same RPM, a larger tire will cover more ground than a smaller tire. Put them both on the same truck, and a larger tire up front will "try" to cover more ground than the smaller tire in the rear. This of course can't happen since they are both on the same truck, so that is why the front tires "Seem" to be spinning at a higher RPM (they aren't..they are just covering more ground because of the larger outside diameter). This is the same effect as putting overdrive gears in the front axle.

I think that is the longest paragraph I have ever written on RCC. Time for a beer.