[Andy Baker]

Sanddrag is right, as the rpm's reduce, the torque proportionally increases.

But, don't forget efficiencies and losses.

On a simple application where you have two sprockets - one on the output of the motor (or gearbox) and the other on the wheel, there is a simple loss in the chain system. I estimate this loss at about 2-5%, depending on sprocket alignment and chain slop.

Then you have losses in the wheel rotation. For a simple system of one properly-aligned driven wheel, then the losses are minimal. If this output sprocket is driving more than one wheel, or if the wheels are misaligned, or if the sprocket is driving treads, the the losses add up significantly.

These losses is where alot of teams get in trouble. If the wheel system is free of these losses and mis-alignments, then you can translate your torque calculations and rpm reductions (with minimal losses along each step of the way) as Sand said above.

Good luck.

Andy