pretty happy with this. Using a low aspect 1200 and the 6 inch lift prop. Next step 7 inch prop and smaller high aspect wing
And this is same front wing and just using a smaller rear wing
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Love the GPS glitch on the top speed in the last pic. Imagine doing 114kph on an efoil, you’d fall apart if you fell!
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You already feel crash above 40kmh a bit haha
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It’s interesting that this value is just based on some datasheet info. I thought there is actually some measurements needed to include wire sizes and whatever. But apparently I have no idea at all.
Are there more of those motor detection values which can be calculated externally? I don’t trust my VESC to do this right 
would it be possible to calculate the resistance out of a metr log (motor current and voltage)
I don’t trust it too. A mate is going to measure the inductance and resistance with an LCR meter
Possible also that way :
Best to measure Ri … of the motor in warm water to simulate the heat of the load
Yes let us now if this works. According to this thread it might be not easy since there is no high load during LRC measurement
Interesting, I will check just out of curiosity. Everything runs really well now. The only issue I have is with 95kg and a small board (125x56cm) I can’t get up using a 850cm2 wing. I can see in the log the motor can’t get rpm to increase and motor current hit the 200A limite. I’m a bit reluctant to increase max motor current further. In the log above you can see the first 3min where I try to get up with the 850 then I swap for the 1200.
This make me wonder what Lift ESC current rating is as people foil on the 4’2 with the 120ha (775cm2)
My guess would be around 150-160 Ish max current, but certainly not 200A imho.
A temperature sensor in the motor would be great.
You could bump up the current untill a certain temp is reached and therefore really get the absolut limit out of the motor before it would burn out.
I really doubt a big guy can get up on a 4’2 (127cm) and 775cm at 160A but maybe I’m wrong.
Well @Manufoil props to you. I did try today with the calc Flux value, in my case it is 120kv motor which has 6 Poles = 15.35 mWb (before I had 16.x-ish). The observer gain would be 4.26%. And indeed the motor runs straight away noticeable smooth. Still I have some syn issue around 90-95% duty, but compared to before it is really damped. So this value has lots of potential for tweaking, I may rise or decrease at a bit to test what will happen. Interestingly, my start is not so powerful anymore, I even needed to raise the motor current to 170amps (160amps before) to take off a bit faster. So now with lower flux I am missing a bit of punch for start and have higher current. Whoever can enlighten me about this, it is very much appreciated. Let me close with a log:
Cheers
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Interesting, same finding here, less punch but it solved the ABS issue and cogging. Run overall smoother. I also have higher motor current to get on the plane. What switching frequency are you using? Depending your setting you can increase frequency a bit or play with stator saturation compensation to try to solve the sync issue at high duty.
When I use the opto seal 300A the motor seems to have way more torque, I’m just worried of how high the motor current is going to get on the plane as you can’t monitore it, in theory it could go up to 300A I guess which I don’t really want.
A variable flux setting, that would be a neat feature. Higher flux setting for low rpm and lower flux for high rpm. Anyway, I think switching frequency is 30kHz and I know about that stator compensation, I think it is more for low rpm and high current, so at start where I have the 170amp
I always felt classic esc like the opto seal 300A have more torque than vesc, probably because max motor current can go as high as the esc current rating…
Noticed this also going from my esc heifi to vesc , a lot less punch and more planning needed
On my heifi to pop of the water got 280A pics ( assuming the capacity of the esc to measure were close to reality and it rated 200A)
So about 21N ( where shaft coupler breaks usually on geared setup )
Not familiar with the seal esc and software , but I supposed the motor takes what it needs : 280-300A
Stall Amp should be over 1000A
For sure you are well over 200A with the seal esc
Trampa suggested to play also with the Ri ( increased by 5%) , best to see the numbers of detection after placing the motor in a 50c water case for a couple min …
On lift vidéo on the short board , he needs to be really up front and it takes some time to get it to fly …
And I tried to get the switching frequency of the seal esc , but no numbers fund : my guess either 16 or max 32mhz
Ri is just meaning the “R” (resistance) of motor detection? Smart idea to put the motor in warm water, I like it.
Yes , better value close to reality under load that way
Never done at the time because it was running nice and I was practicing my turns not going for top speed ( tried of crashing …)
You have a data logger on the Heifi? Do you think 300A motor amp is ok for the FR motor? I’m ok taking the risk with the vesc but really don’t want to burn the motor
Cheers
the only data on heifi was for my tp4070 780kv , after i switched to vesc and sss56104, then FR motor , never took this motor above 150A
by its wires size and low resitance i assume it could handle the same pics as my tp motor
since you already push it to a “constant” 180-200A on top speed , i think it could handle pics at 250-280 for start (probably what the seal esc lets through))
the only way i can think off is to go for “long” run top speed constant high amp then run a detection straight away and see the resistance of the coils