Trolling speed

I am thinking about the rest of this fishing season and coming up with a few questions. In past, I have trolled with screw tails and had luck but was fishing out of a Jon boat or a stump knocker (I do not own either one) and had some good luck.

The question that I have is what speed would you troll a jig head with a screw tail? My 17 Mako with a new 115 E-tec I have a hard time getting the boat slow enough (I feel 1 to 2 mph) to troll. I know that I could hang a couple 5 gallon buckets over the size to slow down the speed but is there anything else you would suggest? Also, a trolling motor is out of the question. Do not have the space for the batteries and do not want the additional weight.

I guess the answer is to tell the wife that I need a stump knocker with a 25 hp motor on back.

You just have to keep bumping it in and out of gear. If you are going with the current, you just use forward propulsion to keep the boat straight. 1-2 mph is the right speed, and you want the grub to tick bottom every now and then.