Trolling motor hack I learned about.......R/C Plane prop to increase speed and efficiency

[AlabamaSpothunter]

I watched a Youtube video a few weeks ago about how you can add a $4 R/C plane prop to Minn Kota 55lb TMs.......guy had a voltmeter and odometer, and he was gaining .5-1mph while doing so with less battery draw.   

 

Well I ordered a pair of these $4 props, and while it took a bit of playing around to find the right washer, it was a direct replacement for a OEM prop on the super common Minn Kota Endura 50lb TMs.   

 

I gained .5mph @ speed 4/5, however was only getting about .25mph gain on the 5 setting.    Either way, the efficiency alone is worth the swap if you aren't around a place that requires a prop for weeds.   I have weeds on my lake but not in the open, they line the shores and back of coves.   

 

I lost "torque" or that immediate get up and go changing props, but top speeds at all speed ranges increased notably.  

 

Lots of YT videos about this, but I'm just now figuring it out.   Minn Kota stock vs apc prop is the video I found.    

 

10x5M-LH - APC Propellers

 

[Alex from GA]

Very interesting.  I wonder if they fit a Motorguide 45 lb trolling motor.  Thanks

[airshot]

A half mph is a big gain ??  To each his own, not condeming here....but loss if torgue and a .5 mph gain would not be worth anything to me, but that is just me. From my research, those moving to a three blade gained a bunch of torgue, better handling a lower speeds but a 1 mph loss at wot...  Gues it all boils down to what you want or need !!    Very interesting though...an airplane prop ??

[AlabamaSpothunter]

6 minutes ago, airshot said:

A half mph is a big gain ??  To each his own, not condeming here....but loss if torgue and a .5 mph gain would not be worth anything to me, but that is just me. From my research, those moving to a three blade gained a bunch of torgue, better handling a lower speeds but a 1 mph loss at wot...  Gues it all boils down to what you want or need !!    Very interesting though...an airplane prop ??

Yeah it doesn't sound like much, but when you are depending on a battery/TM setup to cover 150 acres it matters over the course of half a day.    This also applies to anybody who kayaks with a TM.  

 

My top speed was 3.5mph at 5 speed.   It's now closer to 3.9mph at 5 speed.

 

However 5 speed on a non variable motor eats up the battery.....and at speed 4 it was 2.20mph.......now it pops over 2.75mph.

 

.5mph gain on 2.2mph is extremely significant in my book.   

 

We're not talking 150HP outboards after all.  

28 minutes ago, Alex from GA said:

Very interesting.  I wonder if they fit a Motorguide 45 lb trolling motor.  Thanks

The props are so cheap, I took a gamble on the 50lb Minn Kota and as mentioned with some washer playing around, it fit perfectly. 

 

I imagine if the shaft size is the same as Minn Kota's, it will work.   Folks are using these on 30lb TMs I read in the comments.  

[A-Jay]

My rig benefits from the torque (relative term here for sure) as it's not exactly light.

Add in some wind and it becomes even more crucial. 

I run a double battery deal so juice is rarely a concern.

A-Jay

[GreenPig]

I saw that video and it was interesting,  but I chop alot weeds every trip. 

[flyfisher]

I'll pass.  I am not a big fan of swapping out a prop when I want to be fishing.  .5mph is nothing in the grand scheme of things.  When I was motor shopping I want to say the endura drew between 40-50 amps at max throttle.  So your standard 100ah battery you would gain a whopping 1 extra mile, if that.  Also with me fishing rivers primarily, that torque is important on start up or i could be struggling to keep position in current.  

And for the record, I have an NK180S with 30ah battery and on flatwater can get almost 6mph at full tilt or a little over 5 at 70% or so and my battery will last me upwards of 10+ miles.  On river trips I can easily cover 6+ miles in all but the heaviest current.  

Honestly it seems like something people would do who don't get out to fish much and want to tinker and that is fine, just doesn't make sense to me for a minimal gain in speed while losing in other areas.

[Susky River Rat]

I would much rather have a TM that chugs me through wind, slop and current then that .5mph. Even on the 500 acre electric lakes I fish from time to time. It’s neat someone played around with this but, torque is more practical on the water.

[casts_by_fly]

I have used the prop and can comment with experience here. In my case it’s on a kayak with trolling motor as the primary propulsion. 
 

The autopilot I have is basically a 43 lb thrust power drive in a short motor and special mount on a 150 lb kayak (plus me and gear). The standard motor is the power prop mkp-2.  That motor will get me around 3.8-4.0 mph on flat water and a fully charged lithium. The rc prop will get me to up to 4.3-4.4 in the same conditions. It’s a 10% bump or thereabouts. When you’re transiting across a large body of water with just the trolling motor it’s a nice bump. 
 

At top speed, it draws about the same power as the regular prop. It might be a little more or a little less in your situation, but it was about the same total wattage on mine. 

On the downside, the prop is incapacitated by weeds.  Maybe because it doesn’t have the full housing, maybe because the blades are thin and long. I’m not sure. But the tiniest weed collection makes the prop unusable. Also, it’s far less robust than the standard prop. It has a lot less plastic to take the brunt of a hit on a rock or stump. The plastic is much thinner than a normal minn kota prop.  Maybe because of the thickness, maybe the material but I find it loses its edge a lot faster and is more prone to chunks breaking out than the normal minn kota prop. 
 

in contrast, the weedless wedge prop (mkp-6 for me) loses 0.6-0.4 mph compared to the power prop (mkp-2). What it gains is a lot of low end torque and ability to blow through weeds. It literally blows them away when you turn the motor on rather than spinning up fast and wrapping around them.  
 

for me, I carry all three.  Early season I put on the rc prop. The lakes don’t have weeds. I value the speed in my boat that is electric motor limited. I also use it this time of year on the lakes that don’t have weeds.  Around April/ may I swap to the power prop. It’s still pretty quick and works okay in weeds. Come the end of may when the weeds get thick, I swap to the weedless wedge. It’s simply the best prop for the lakes I fish from may to October. I’ll give up the speed to ensure it will cut through as much of the weed growth as possible. 

 

all that said, I carry all three on the boat at once. One mounted, the other two ready. If I get somewhere and am surprised, then I can swap on the water with one nut. For the most part, I don’t need to do that. It’s only once or twice a year. 

[AlabamaSpothunter]

2 hours ago, flyfisher said:

Honestly it seems like something people would do who don't get out to fish much and want to tinker and that is fine, just doesn't make sense to me for a minimal gain in speed while losing in other areas.

I don't tinker, and I fished over 250 days since Aug '22 ?

 

You're comparing your $1000 electric outboard kayak motor to a run of the mill $200 50lb Endura TM with a $4 R/C prop.   Is 2mph worth $796 more to you?

 

Eventually you realize on forums it's just easier to not share, maybe the mods can change the title to "which line for chatter cricket widget" 

 

 

[Bankc]

I did the same thing to my trolling motor.  And I agree, it's much better this way.  More efficient and faster.  You do lose some torque, but in a kayak, you don't need that torque.  You're not pushing much weight, and all you lose is a tiny bit of acceleration.  It handles wind and current even better with the increased efficiency.  Weeds might be a problem.  I don't know.  I don't fish a lot of lakes with much in the way of weeds, so I've never had an issue.  And I pull my trolling motor up and paddle over thick weeds anyway, as I can't access my stern mounted prop from sitting inside my kayak.  I will say, however, that getting weeds or line out of the RC prop is a lot easier than getting line or weeds out of the standard prop.  With the standard prop, I have to pull the prop off to get under the cover.  With the RC prop, I can get in there without tools or fear of losing the pin.  

 

The only drawback that concerns me is breaking the prop.  I've yet to do that, but it is a lot thinner, so I could see it breaking more easily.  I'd bring a backup with you, just in case.  I bring my old prop, and of course bring my paddle so I've got a plan B and C should it ever fail.  

 

I think a lot of these people are just weary of change.  Especially when it originated from a YT video, which as we all know, has more bad ideas and loud voices than good ideas.  But I think this is one of those cases where the idea is actually really clever.  Now, I could see why this wouldn't be a good idea on a bass boat, as with a bass boat torque is much more important than speed or efficiency.  And you can easily access and clear your prop on the water.  But in a kayak, the RC prop is the way to go.  In fact, if I was Minn Kota, I'd make a kayak specific version of my trolling motors and include a prop like this and charge more for it.  Or better yet, design a toroidal prop for even quieter and more efficient operation.  

 

This is one of those things, that until you actually try it yourself, you won't really realize how much better it is. 

[airshot]

Never down people for experimenting or thinking outside the box...look back in history at all the things we would not have if someone wasn't tinkering !!  Often someones tinkering might seem useless but it gives way to other ideas.  While his article may not have been beneficial to me in my situation, doesn't mean it didn't help someone else or get someone thinking about another idea.  I read all the tinkering stories I can find, some are corny, some crazy, some usefull and some funny, but at least it keeps my reading skills up to date !!