Rod Pump: 2005 #18 (similar)

Q: What pumping unit change reduces torque the least? 1) Reducing stroke length or speed, 2) Changing rotation direction, or 3) Installing larger rods?

A: Reducing stroke length or speed lowers torque. Larger rods? This doesn't "reduce" torque at all. So that would be my choice.

On a sidenote: changing direction is a bit more tricky to consider. Why? Class III (& Mark II) API specs recommend the crank arm rotate in the counterclockwise direction only. Class I can operate in either direction but this is not recommended for many reasons. Greater torque spikes clockwise is one of them.