High Torque DC Motor
When you have one motor drive another, the second is no longer a motor, but a generator

There is a relationship between the current draw and torque, generally it looks like this:



(image from Pololu)

Gearing can increase torque at the cost of speed and efficiency - I also have yet to see a fixed RPM DC motor - they may have an unloaded RPM for a specific voltage, but RPM will vary greatly depending on the load