Originally Posted by MleedM

So using "R/C Car Gear Ratio Calculator", I have a Gearbox ratio of 2.5, Spur of 72 (right??), Pinion of 27, RPM around 20,500 and I'm guessing tire diameter of 2.2" (slightly worn GQ's ... what typically is the diameter of new tires? I don't have access to them right now). It says that my to speed is 20mph? Would this be about right then?

thanks