Originally Posted by cannonball2
...is simplicity. ..
simple. I need to improve my diagramming abilities. The way I have it shown makes it look more complicated than it is.
I don't like "direct" drive (if you mean the motor shaft being what holds the roller) because to get an appropriate gear ratio means a roller with a small diameter (perhaps less than 2 inches). This give inadequate engagement to cause the stopped tire to intern kill the engine. Thus, on some occasions, the roller will grind into the tire.
I'll provide an improved diagram of my plan in a bit.