80100 direct cooling

Sweet! Is there really no company selling pre epoxied motors for aquatic use? Seems like there would be a market for that!

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if there were, they would appear on ROV forums… but some are starting to market ESC and motor for Efoil, so may be they’ll start epoxying soon… however, it’s not very difficult to do either…
the harder with those big motors is to separate rotor and stator… and put them back together… making a jig for that help a lot though…


Do you have any STL files for your setup? They would be much appreciated. I have been trying to use this motor and can’t ever get it figured out. Mine always loses sync. I haven’t coated my wires though. Could be the answer.

I have two other setups to try. One with this motor:

Another a dual 6364 motor, with one in front and the other behind the foil. Hope to some day actually ride.:joy:

Sure, i’ll share the fusion file tonight… i need to make the parts visible from my home computer first it seems like.
There are actually not many printed part, mainly the one that links the mast to the motor.

I’m not sure that motor you have on the picture will do it. the wires seems very small, and i’m not sure the sensor part is easy to waterproof, that’s why removed mine… i didn’t want to deal with waterproofing all those extra wires…


Mi @Mat, It will be nice if you can share your files and build since it looks very promising and simple. It also should be very efficient since the power is not dissipated in heat.

BTW do you have any details of current and voltage measurements related to speed (gliding and flying)? Max numbers? It is very valuable since from other measurements in this forum it suppose to be under the 1Kw in very extreme and maximal situations.

Thanks. It would be awesome if everyone shared the stl files. Some of us don’t know how to use Fusion 3d.

I did manage to print a prop that surrounds the c80100 motor, so its all built in one. It will screw into the can holes. Don’t know if it works yet. Like I said, I had issues with the motor losing sync underwater. Maybe coating the wires stops that, but maybe just having the wire covered will help.

That motor above is like two of the c80100 motors. I ran it on a kids electric motorcycle that my kids are now too big for. Should be good for 5kw. It runs at 4500rpm on 48v. I could overvolt to 60v. It’s interesting that I haven’t seen an ebike controller version of the efoil yet. Having an attached throttle seems ok on this. Not so much on an esk8. The ESC has much better current control than RC stuff and shouldn’t light on fire.

Sometimes I wonder if I just like making something work instead of actually riding. I have most parts to build a Pacificmeister setup, but I want to see if my own projects work first.


well i am not sure about the motor shown above, my kid (3 year old) has bike like this, it is really fun , i drive it as well !
by the size of the gear look more like 800-1000w, and it’s really heavy and not much torque, c80100 is way more powerfull !

and you can attache a throttle to any esc with the help of a servo tester

this is a 5000w set up :wink:


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that’s the fusion files,
note that the screws go through everything and thread in the motor itself
and it’s made to have the wires running outside the mast on the front and you can print the 3rd part as many time as needed to protect the wires all long the mast.
it’s not a clean model at all :slight_smile:

and no, i don’t have any measurements in the end… my wattmeter wasn’t readable while riding, and loose memory when the power is shut off… and each test ended with the beaker tripping or the ESC heating and turning off… :slight_smile:

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thank you very much, to you the rear with the propeller?

for the circuit breaker i have try to put in between the 2 battery , they are rated for 42v i think

the propeller is a commercial modified with 2 holes to get screws reaching the motor.
and i added that piece between the prop and the motor to fill the openings to reduce losses… it’s not perfect at all… just good enough… i’ll modify it to fill the gaps better for the final versions.

Be careful that your motor has the same pattern of the openings… i noticed a few different ones online.

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Download files here:
c80100 files

Thanks again Matt.

That motor is twice the size of the c80100 and twice as heavy, which is the biggest problem. Runs at about 100kv, so 4500 rpm on 48v, perfect for a waterprop without reduction. I ran it on the motorcycle at 5kw peaks using an amp meter. I tested the setup today without load and it ran 1500w at 44v and 36amps. RC stuff is way overrated. The c80100 motor has been tried on tons of ebikes. Usually it is just the RC ESC stuff that blows up, but that motor c80100 motor burns up too. Both motors aren’t really high end, I know that. Ebike stuff is always way underrated. The 1000w hub motors can take way more than that. You can judge just by the amount of copper. I mentioned using a connected throttle as on an esk8 it doesn’t make sense, but on the efoil it isn’t really a big deal. A servo tester was used on my kids motorcycles with the c80100 motor. The idea is being able to use an ebike controller which has much better amp control, an RC esc has none, which is why they all blow. It makes more sense than using a cheap RC ESC, which ironically isn’t so cheap.

Is this going to be enough power?
Youtube test


well , i didn’t not push the motor of the bike yet, you may be correct because of it’s size, but the power on wattmeter is not the final power on the drive , especially if you have like 60% efficency and you loose rpm under load also

c80100 with bike i think it is because of the “direct drive” and applying full throttle at start ( @ probably 200Amp peaks)

nice video:

on my foil i cannot hold the board at all at 1/2 throttle, but as soon as i an standy on it, i want more power full throttle…

i guess you have to try it on a decent sized board, good luck :wink:

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Hi @Mat, How is it going with your tests? can you please provide the link to the propeller that you have used?

You mentioned that you 3d printed the hydrofoil.

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Test are on hold pending a new remote and new board being made… :slight_smile:

That’s the propeller i bought…
it’s plastic, so quite easy to modify to attach to the motor.

For the foil, i started my trials with a big custom front wing… that one was 3d printed and covered in fiberglass… But the rest of the foil (mast, fuselage and rear wing) is a foilfish from liquid force.
It was a very fun wing to kitefoil, possible to surffoil, so i though a good match for efoil.
The i did the second try with the original foilfish front wing. and it made the ride a bit more stable…
I’m not sure if it’s because my remote trigger wasn’t sensitive enough to ride a low speed, but the smaller wing was easier at higher speed…

And recently, i bought the liquid force impulse… the front wing is pretty big, and the lift is insane… for surfing, it flies at extra low speed and is veryyyy stable, so i’ll definitely try it once my new board / new remote are ready.


the most irritating thing about that prop was it came with a 12mm mount. I had to print an adaptor for a 10mm shaft.

As i have a custom short shaft and the front cap acts as a spacer, my shaft doesn’t even touch the prop… instead it’s screwed from the front to the motor itself. It might be a slightly wobbly…
My plan is to thin the from cap, slightly slide the shaft toward the prop so it centers is properly.
and 80100 have 12mm shafts :slight_smile:

You can buy this propeller with 10mm adaptor et the pin but most offer is just the propeller

Do you have a link to the adaptor?

No i didn’t find it , i just use an alloy tube 12x10 on my shaft

after a few weeks in the dust, new board is coming along…
all hotwired from a block of polystyrene, Plywood stich&glued for the electronic bays that extend inside toward the back and the foil screws to it. each bay is watertight from the next.
Old mast had some issues… new one is perfect, quite thin and plenty of space for the wire… but new motor holder needed.
The Plexiglas windows will have some round hatch for easier access.

it’s all filmed for a movie coming… after first flight!