I have a 9.9 hp 2-Stroke kicker on my 170. It's clamped on to the transom without a bracket and there's plenty of room to use the tiller. I do a lot of speed trolling for Musky, Pike and Salmon here in Illinois. It moves it around pretty well, I haven't checked top speed on the GPS but it's probably around 6-8 mph. I would think that a 9.9 or a 15 would work well on a 19-6.