Motor for the PA17T

Hi All,

Like many others that have gone down this road recently I am looking at both the Torqeedo 403 and the Motorguide Xi5. I know there's already a lot of posts here concerning trolling motors, but not much specific to the PA17T. I think it also may be helpful for me to describe my prospective use and expectations of a motor.

I will be using this primarily in Narragansett Bay, RI. The bay is big and the biggest challenge for kayak fishing is launching in the right place so you can get to where you want to fish in a reasonable amount of time. The PA17T doesn't need a boat ramp, but it DOES need trailer parking, and that can really limit where I can put-in.

I have used the PA17T in both tandem and solo mode. Surprisingly, I found that my Speed-Over-Ground was not very different with or without another person pedaling. Solo, I have comfortably kept a 2.5 to 3.5 MPH SOG (varying with wind an current) for 3-4 hours straight before wanting a break. Going much faster requires significantly greater effort. Even in tandem mode I had trouble reaching 6 MPH even with full out effort. The boat doesn't FEEL slow - it seems to cruise right along at a reasonable pace. But on the bay, I can expect to want to go 3 or 4 miles (or more) from a launch site to fish. The hour+ to get there, and especially the hour+ getting back when tired, can be pretty significant.

If I could reasonably expect a motor to move me at 5 MPH for a few hours that would have a huge positive impact. I LIKE pedaling. Having a human-powered craft is part why I went with the PA. But I'd sure like a little more speed, and I'd also like the added safety of a motor to help get me home when I'm out solo.

So between the 403 and the Xi5, there seems to be a consensus that the 403 is faster. But I guess that's at top speed which will run the battery down awfully fast. Advocates of the 403 tout weight as a huge plus, but I don't see that as much of an issue with the PA17T. It's already a beast and it has a tremendous weight capacity. The weight of motor and battery when carrying to and from the car or house is still an issue though.

Regarding weight, I haven't seen anyone talk of using a LiFePO4 with a conventional trolling motor like the Xi5. Given the expense of Torqeedo batteries, I think one should consider the possibility of a battery like this for the Xi5: http://www.batteryspace.com/lifepo4-26650-rechargable-battery-12-8v-65ah-832wh---replace-sla-battery-with-lighter-weight-and-higher-capacity---un38-3-passed-dgr.aspx . If I understand correctly, a 65Ah lithium battery should give about as much run time as a 125Ah AGM (such as this: https://www.amazon.com/Vmaxtanks-Battery-powerboat-trolling-MR137-120/dp/B0042L7DZ8/ref=sr_1_13?srs=5475964011&ie=UTF8&qid=1469481390&sr=8-13 ) because you can run the Lithium battery down all the way. The LiFePO4 above weighs 22 lbs. The AGM weighs 75.

Regarding energy, the 403's battery holds 320 Watt-hours, and the LiFePO4 referenced above holds 832 Wh! If one assumes that only about half of the AGM's energy is usable (because of voltage drop), it still has about the same as the LiFePO4 but for far less cost.

Anyway, I guess for me the speed/efficiency issue comes down to being able to go 5 MPH for let's say 4 hours. I think the Torqeedo would require the battery from the traveler series to do this. Since you have to buy the standard battery anyway, you might as well bring both with you. With the 530 Wh traveler battery in addition to the stock 320, that's 850 Wh. Do you folks think that would be enough to push a PA17T at 5 MPH for 4 hours?

The 12V LiFePO4 above is about the same energy. How much less efficient is the Xi5? Do you think the Xi5 will do 5 MPH for 4 hours with the 832Wh battery?

Another question I have concerns the fact that the PA17T is much longer than any other PA - I wonder how that affects the speed and efficiency that could be expected from one of these motors? It should be better, right?

It seems that the Xi5 is intended to mount on the bow with Hobie's PA17T mounting bracket. It looks like the Torqeedo is normally used with a DIY mount on the stern. What is the impact of the mounting location on speed and efficiency?

In the end, I guess I'm trying to convince myself that the Xi5 is the way to go. Mostly because of the GPS functions. Having that anchor function sounds really cool. Hands free guidance also seems great for using both hands for fishing preparation instead of having to constantly hold on to the rudder control while under way. Also reentering the PA17T is easiest from the rear which makes the bow mount attractive from that point of view also. And lastly I like that my Fish finder and any other 12V electronics can run from the same battery.

What do you think?

I run a island hopper 55lb thrust motor and a heavy battery https://www.amazon.com/gp/product/B0042 ... UTF8&psc=1

If we are fully loaded, the trolling motor keeps a steady 2.8 mph for the day at full speed without pedalling. Only way we are able to get these results is by pulling the skeg and rudder up and using the motor to turn. With just the rear seat keeping a steady pace, 4mph is easily reached and maintained.

By full speed you mean the fastest of your 5 speed settings? Do you think that would be roughly the same current consumption as WOT on a Xi5?

When you say "all day", approximately how many hours of running at that speed would you say that is?

You are saying that with two people and gear on board your top speed is 2.8 MPH? And by just reducing the cargo weight it goes up to 4 MPH? Approximately how much weight difference?

I've heard that the prop characteristics can really come into play here. Does anyone know how different the island hopper prop may be from the Xi5?

Thanks for your input!