i want more top end speed than I'm getting now. Just under 4 mph. 10 would be good. Any recommendations?

What's she rated for? Is there plaque with Max HP?

Sure - what's the rating? Is this a square-back canoe?  A small gas motor up to 3hp or so might work well. If you have a longer, heavier canoe, you might be able to run a higher HP motor.  BUT, whether you can get to 10 mph might still be a challenge.

 

If you are using an electric trolling motor now for propulsion, you might benefit from a higher thrust motor (depending on what thrust you are running now) - but the benefit would only be on the order of another 1 mph or so.  With many canoes, especially those with wide beam, you are running into a "hull speed" wall (Google "hull speed").  You could add a significantly higher thrust motor and may not see much speed increase.

 

I've seen canoes with gas engines move out at a pretty good clip, because they have enough power to get the canoe sorta on-plane, thus getting past the hull speed limitation. However, when I've watched vids of these canoes, they don't seem like the most stable & controllable machines.

 

For reference, I have a 45lb thrust TM on my 12' canoe that only weights 34 pounds empty.  BUT, it has a 38" beam - thus giving a dismal (for speed) length-to-beam ratio.  With me and all my gear, I used to top out at about 4.5 mph on the GPS.  I would hit that top speed at only about 3/4 throttle - adding more power didn't add any more speed - that was the "hull speed" factor coming in to play.  My TM seems to be getting a bit tired and I'm topping out now at about 4- to 4.2 mph or so at full throttle.

What size canoe, is it a square back for a motor or are you using a side mount, and how scary do you want to get.  I have a very old, 17' Grumman cargo canoe (fairly wide and flat in the middle) with the square back and a 4 hp merc I use on it sometimes can raise the pucker factor  if you are not careful.

Forget Gas - 

 

The troller is so much more stealthy.

 

I run 2 batteries (one forward & one aft) - it's sweet.

 

A-Jay

 

That sounds really sketchy.