[RickeyD]

Originally Posted by Dr Winston O Boogie jr

The problem with your whole theory is that that the tires do not control the rate at which the axle spins. The engine and transmission determine how fast the axle spins. Putting on a larger tire means that a point on the outside of the tire will move further in the same amount of time that a point on the outside of a smaller tire will move if the axle spins at the same speed thereby traveling further in the same amount of time.



For example, if the outside diameter of a tire was 12" the the circumference would be approximately, 18.85" A tire with a 14" outside diameter would have a circumference of 22". The 12" tire would travel 18.85 inches every revolution and the 14" tire would travel 22". Assuming that the speed of the revolutions is the same, the larger tire would travel 18.85 inches sooner then the smaller tire. Or, the larger tire would travel 22" in the same time that the smaller tire travels 18.85 inches. Either of which is the definition of going faster.



The argument might be that putting on a larger tire may make the axle turn slower because of the weight. If that's the case, then we'd have to know exactly how much slower the axle turns and exactly how much further a point on the outside of the tire moves to determine whether the cart will go slower, faster or the same. But, in my experience and in the experience of most experts that I've spoken with, larger tires will give you a bit more speed. In other words the amount that the axle is slowed down, if at all, doesn't offset the additional distance the tire will travel.



Another point is that if you put larger tires on the back of the cart and not on the front and your speedometer is attached to the your front tires, no adjustment to the speedometer needs to be made. The speedometer is simply measuring how many revolutions the tire is making and multiplying that to how far each revolution make the cart travel.

A voice of reason and logic within a thread of misunderstanding and chaos.