Hi,
what propeller did you tried ? With 7000Rpm the diameter / pitch must be lower than in usual setups.
It was a high pitch torque design kinda like a regular outboard. Agreed it wasnt ideal and the likely reason for the failure. Just wanted to point out that cassie with the factory email and said it had a thrust bearing and after melting realized it doesnt.
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I suggest gluing a thermistor (e.g. any 10k NTC with known beta value example NTC from mouser.com) to the motor winding head. I have had some in multiple locations. It is pretty easy with a Multimeter to watch the resistance during a test and abort testing if the resistance drops below a certain thresold. This threshold directly corresponds to a certain temperature. If you want a direct Temparature reading add a normal (non ntc) resistor and using for example the popular arduino boards to display the temperature directly. This is however not necessary if you only want to prevent the motor from overheating during tests. (A quick web search shows this example for arduino ntc temparure probe.)
Do you use the 83110 for efoil? Im thinking about trying one. Just not sure if it will handle the power…
The water cooling would make it possible to fully seal the motor and still keep it cool.
That is the motor I used last summer. But I made changes to it. I rewound it from its original 180KV to about, I think it was 116KV. I also made a different back for the motor out of aluminum. Most of what I did is in that thread For who try/have tried direct drive with outrunner
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Jake,
Of all the problems I had, the motor burning up was not one of them. I did always have about a spoon full of mineral oil inside the dry pod. and unfortunately very often about a spoon full of lake water in the dry pod also. That may have helped with the cooling.
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Thanks for the reply Mac!
So you were foiling with that motor, do you know what current it was drawing?
With 56200 it was not possible, but I could only feed it with 80A at 50V
Why dont you give it a try? Sloppy 4kW? Is this really too low power? Why dont you cool the motor from inside with water flow? 3000-5000RPM should be no problem if you secure the windings and stator with some resin.
Yes, I foiled with that motor. I really was never up continuously on the foil for more than 20 seconds. So if it was hot it had plenty of time to cool. No I don’t know the current. Without my glasses I could only read my displays if I was laying on my belly. The motor had more power than I needed to foil. Without me on the board it would easily hop completely out of the water from a stand still. Maybe that’s not a big deal but I thought it was cool.
The original 180KV was pulling way to much phase current. Thanks to Power Glider explaining to me what was going on.
I have a new 83110 180KV, its new in the box. just in case my attempts to use the 80100 fail. If I use the 83110 I will attempt to change it from delta to star to avoid rewinding it. This will lower the KV significantly.
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Hi Jake,
Did you by any chance got the time to test the 56200 you ordered ? Any logged values ?
How is it performing ?
I only ever did a rough test in the pool and didn’t get any power values etc. I was holding the motor with my hands and I can confirm it has a fair bit of torque (was rotating in both my hands) and a fair bit of thrust. But it got hot quick, the motor was partially submerged deep enough so the 3D printed prop wouldn’t cavitate.
Maybe it could work. But I didn’t bother with it. I’m confident there is enough thrust to maintain fouling but probably not to get up from a start and it would be pretty low power.
Interesting ! thanks for sharing the info 
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No problem! 2 together would definitely work
I found following formula that gives roughly the torque of any BLDC/PMSM motor. This one is really easy to use and no calculator is needed anymore :
T = (8,3 * Imax) / Kv
Calucated the 83110 max torque and found 6.92 NM which is pretty close to the stated 6.5 NM…
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Yep work for me : 1,54Nm for my first step up with a 40mm , these was what i measured with rpm , rpm drop , I , Rm … at the time
But I guess it s all depending on the correct I max , and it hard to get correct numbers for motor , and what it is I max really ? : just before everything is burning ? And how long can it hold that value ?
I got around 1,5 Nm on my motor but it was kind of continuously , more than 250A pics for take off , even if the number was hard to record at this amp value by my esc at the time ( I suspect)
a 80100 can easily pull more than 180A for take off ( for sure) which give 12Nm , and I think it s capable of a lot more before it is stall if well driven , so I am not really sure what s stand for « max » , as well as « continious »
I guess we’ll rely on manufacturer’s specs 
That’s how we know about those values.
Just like the SSS56114 inrunner capable of 13kW peak but stated Imax is 93A @ 130V for the 360KV value, which gives me about 2,1NM.
I know it can pull way more A, but still, that’s what the specs gives.
Given this formula , I need 4,5nm to fly at 30km/h right now 
Is it weird ? Do you consider the gearbox ?
I just had an interesting idea. Based on this formula I calculated the torque of the FR motor : (8,3x100)/130 = 6,38NM
I took 100A peak but I think you can pull more to get on plane. Feel free to correct me.
6,38NM is better than the other outrunners haha. That’s how they get so much punch !