On a typical roller setup (a frame, 3 drums and a belt)...

1) What is the function of the belt between the front and middle drum?

2) How would removing the belt affect riding them?

3) How would removing the belt and middle drum affect riding them?

4) How would removing the middle drum but running a belt between the front and rear drums affect riding them?

5) Why do smaller diameter drums provide more resistance than larger ones?

6) Should I have posted this in the mechanics forum?