Is SSS 56104 KV500 motor really 13000w?

EFOIL.builders Propulsion System (Motor, Gears)
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Hi guys!
I just started to build my own efoil and I’ve ordered SSS 56104 KV500 motor from aliexpress.
I’m justwondering is this motor really 13000w? If so how much in hp? And also if you guys know many suitable esc for this then pls recommend it. Tnx!

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You can only reach 13000w if you push the motor to 45000rpm, so that would mean running it on around 100v.

This motor is mostly used around 15-25000rpm with our efoil or jet setups, so the realistic power output of this motor for our application is around 4000 - 6000w with good cooling depending on how many rpm you are able to push.

At 13000w it would need to be fully submerged with good thermal conductivity and would only handle those power levels for a burst of a few seconds in my opinion. So no it is not really a 13000w motor.

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I see. Which esc would be great for this motor?
Thanks :slight_smile:

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For the ESC, mine is the old version of Flier 400A 16s

It took me months to figure out the best way for the water-cooling without getting kinks in the tubes, kinks = overheating = fire.
So I used 1/4" PE pipe/fittings that I heat and bent to shape.
This (old) version has very complicated and inconvenient cooling configuration so any soft/silicone tubes will always get in the way.

Please, save the headache get the new one with the white shrink.

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Thanks! As a complete novice this efoil esc thing is such a nightmare lol. But I now understand little bit about this Esc system. Btw how much is the normal voltage to run this motor and what will be the maximum Ah for this? :slight_smile:

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There is no „normal voltage“ but due to the risk of electric shock, most people run on 12S (50V), some run it on 14S (58V).

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Few years ago there were a surfboard out there running a gearbox setup and this motor ( like a 700kv) at +200A
So yes 10-12kw for a few minutes …

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Thanks! I’m gonna get the 12s battery for this motor

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That’s cool. Wish I could know better about this setup things. It’s so complicated and difficult for me :frowning:

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Depending on the battery type, LiPo or Lion, with or without BMS, it could make sense to split them up in 2x6S in series, especially if you go without BMS, most balancing chargers max out at 8S.

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Yeah that’s my plan so far. I’m gonna split them up in to 2 6slipo. But I’m just curious Isn’t it dangerous using batteries without bms? Sorry I’m super beginner so I know nothing about this.

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Just spend some time reading the forum, there is plenty of information on all relevant subjects to build an e-foil.

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Thanks man. I will :+1:

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@Alexandre hey Alex, maybe you’re talking about this one?

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There is a general principle with BLDC motors; they are more efficient and will deliver more power (in theory) when you use high KV numbers.

This is because the magnetic materials in the motor stator that make such strong forces (and higher torque) at low Kv are lossy and heavy. The conductors loop around them and that is your electromagnet.

If you use high enough KV, you can even get an air-cored BLDC with no ferrite/magnetic materials, so only copper wire loss which is low. But moving too far in this direction has drawbacks. Very low torque, and high rpm to get the higher powers & efficiency. all your efficiency gain is destroyed in bearing losses, gearbox losses, poor propeller operating conditions, etc.

And IMO I don’t believe the 13kW thing for a second. That’s a theory only number. Even if achievable it’ll eat your motor in 1min.

However SSS are still great motors. If you want to use that motor, you might want to work through the chain backward from the propeller. The single best way to make a power improvement (IMO) is in propeller design. You want a prop speed under 2krpm, or as low as you can go. High speed props have drag problems, poor efficiency. I would aim for a big 750rpm prop with two or three blades. So your 45krpm motor reduced to <2krpm? How do you solve that.

I’m sure it can be done, and a 500kV can make more power at the prop, waste less energy and produce less parasite heat than a 365kV for comparison, for the reasons I’ve mentioned. I don’t know reduction gearing well enough, but I would expect a belt drive is a good way? Someone else can comment here, I’d love to know any good ideas. I’ve always wanted to have try two belts, two motors 180’ apart driving a shared shaft. That’s how you’d get >10kW.

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