Pitcher, I had a Hacker on my Jaguar and it did the same thing. My Jag had a Merc 250 XB and would run in the low 80s. At these speeds, the trolling motor was spinning so fast that it would pull the bow of the boat hard to the right. I had to limit my speed to 55 mph to avoid severe arm cramping! I finally had to trade the Jag in on my 2008 Puma to lower the speed to an acceptable level. April Fools (well almost). You shold not have any problems with the prop spinning. Be careful though, the prop can contact the deck if the trolling motor bounces a lot. I cured this by strapping the trolling motor shaft to the mount. Be careful as well, it is possible to catch the prop between the mount and the boat when you are stowing it. This is a sure way to break one of the blades.
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