I have some heated grips on my motorcycle 13.2vdc. I need to regulate the heat because theyare too hot. The two grips are in series and are supposed to be about 11W each. Of course the temperatue varies a little from idle to 3-4000 rpm due to voltage. Using a 10W 2ohm resistor in series gets them to the perfect low temperature but I would like to control it with a potentiometer. The closest one I could find is a 3W 25 ohm at the Shack. I'm thinking of that with another 5 ohm resistor in parallel. Will this give me the control I need? Ultimately a 5W 5 ohm pot would be ideal, but I cannot find one.