FYI trolling bags do work, my boat 19ft islander 3.o mer motor. 4 BLADE prop 46in wide trolling bag set out from the middle of the back of the boat on a hook swivel and 8ft of rope. 800 rpm 1.4 mph 900 rpm 2.2 mph 1000 rpm 2.6 mph. 12 pitch 3 blade even slower, you do give up top end speed, 12 pitch prop 4000 rpm 20 knots, 4 blade prop 4000 rpm 28 knots. Hope this helps anyone looking to get to the correct trolling speed they want.
