To go beyond 60kmph, you’ll need a foil like this: 600 + 700cm2
With the proper airfoil section:
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Nonsense!!! A dual wing thing like that is pointless. I am 90kg and ride a 56mm wide kite wing sometimes. There’s no advantage to have a random wing poking about in the air…
Just use a wing like this which is rated up to 70kph
https://moseshydrofoil.com/products/front-wing-671-race-surf-wing-windsurf-570-cm2
I’m disappointed you missed an important detail: you’re 90kg but your board just lifts 45 to 50 kg due to the kite lifting component when stationary at 10 o’clock. On an efoil, the foil lifts 100% of your weigh (90kg) plus the 30kg of the efoil = 120kg that’s three times more lift that a kitefoil has to provide with the same rider.
That’s where the top wing could come handy, time for the bottom wing to generate enough lift while gaining speed for your 120kg…
Yes, 80kg efoilers can use windfoil front wings but those wings are still large. To decrease the front wing wet surface under 600cm2 and go fast, there aren’t many possibilities.
You make way too many assumptions!
I’m riding it on an efoil!!!
Good news. If 517cm2 is enough for your 90kg on an efoil, this means you could “probably” split your F wing into 300 and 200 
Yes, 300cm2 is a stab surface.
The stability becomes an issue with a low wingspan. I definitely wouldn’t want to go under 500mm wide.
I wouldn’t ride a staggered setup for speed though. If you are riding fast and you catch the second wing its going to create havoc and probably throw you off the board.
The next step is to build a custom fuse to see the difference my 560 has in a std vs canard setup. But that’s not really what this topic is about…
@jakebarnhill1 try get slingshot to send you the one circled in this pic…
Tell them you want to break records and need their help.
And here I am with my 2300 CM² and 65kg (rider) 
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I think you are right I need a faster wing… the rpm would’ve been 4800 or maybe more, with the runs I did on the charge before when the battery went down a bit below half and lower motor current limit I had a chance to glance down at the remote and at 49-50kph the rpm was at 4650rpm. So I would guess on the 54kph speed run it was at roughly 4850rpm.
The prop pitch is 8.55" or 217mm and 140mm diameter. Similar shape the the early ones FR stopped selling.
So 4850rpm (estimated) x 217 would be 63.14kmh with no slip. if speed was 54kmh that is around 14.5% slip.
Another point is when the prop is unloaded on 16S at full throttle the prop is doing just over 6000rpm, that’s over 30k rpm into the gearbox lol, the motor is definitely under some load to be dropping the rpm that much, that also doesn’t factor battery sag which there was a fair bit of with the 16s11p 25R pack.
@Ackermann metr does seem like a much easier way to do it, at least with the rt data on the VESC app screen recorded it turns into an interesting video…
You can do video overlays with Metr as well. Also, the Metr logs are super nice to browse through especially if you logged GPS coordinates as well. metr
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I can’t believe no one has commented on the ending yet! Great way to finish the video, haha.
How did that crash feel?
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You have a 5:1 gear ? That is a 20% drop which is not bad , with my first geared setup (6:1) but a 40mm motor , no current control and FR first prop , I had 30% drop , 38km/h at around 3100rpm with this prop ( really close to yours)
But your watts at top speed is more than the esurf (2017) with the similar setup I recall , so it can definitely be better I think
Thank you for your video , nice skills !
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@foilmore thanks! hahaha it was enough for me after that, got straight out of the water Wearing a wet suit does help with those high speed crashes though.
@Alexandre yep its 500KV with the 5:1 gear. 20% drop probably isn’t as bad as I was thinking.
I think something weird is happening to the VESC motor current limit when pushing the motor to these speeds, I highly doubt there would be 255A flowing into the motor. 57.6 (nominal 16S voltage x 255 (motor current limit) gives 14688W, there is absolutely no way there was that much power going through it. If I had to guess I would say no more than 8kw was going out fo the battery. maybe 255A is the current at the peak of the sine wave but the average current is less. I remember @Giga talking about this a while back…
I struggled a fair bit to get it to run the motor without it stuttering and losing sync above like 45kmh when I first tried 16S. Increasing the stator saturation compensation to 10-15% helped but only allowed a little more power. turning the foc sampling mode to “v0 v7” helped bring the power up more but it was still losing sync. Then there is a setting called observer gain and that solved everything, it was originally at 82, halving it to 40 made it lose sync much earlier and have worse low end acceleration, then increasing it to 160 made it better but it still would lose sync but at a much higher speed. I then increased it to 240, and it made it absolutely perfect and the low end performance was improved. Better acceleration and it felt like the motor was being run smoother.
So to people using the VESC I would recommend trying to increase or decrease the observer gain and see if it improves anything! It seems like a setting that is safe to adjust.
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I’d say this would be pretty close to what you would be seeing:
To get to the 60kph mark, you will need a prop slip of 4% (which will be near impossible to achieve) or squeeze some extra power out the motor. The most efficient I have ever run was 7% prop slip. Time to to rebuild the pod and put the 124mm 500KV in, or a 750KV 
Looks like a nice calculator 
Do you mean with my current wing 60kph wouldn’t be possible or with a smaller wing? I think with a smaller wing the required load is less so the motor will spin to say 26500rpm instead of 24000 rpm, and prop slip may drop to lets say 10%. In that case (use a smaller wing, everything else the same) the top speed would be (26500/5)x217x60 = 69kph with no slip, and with 10% slip. 69x0.9 = 62kph. So with a faster wing I think over 60kph is possible without changing anything. a 124 700KV would be cooked, that’s got to be the best way to get to 70kmh!!
Does this sound right?
I say just chop the wing way down wing and triple your power and prop pitch. Ever seen how much of a bass boat hull is touching the water at 100mph? Nothing but prop and skeg, baby! (Until that bitch chine walks and you end up on youtube demonstrating the boat version of a tank slapper, LOL)
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Liquid Force Happy Foil is a small good Wing, he can 3km/h more then the rocket foil (by 6s Set up).
Greetings Frank
For VESCs you set the peak motor current (the maximum your motor will see at any time) which is sqrt(2) x of the RMS when running FOC (since it is a sinus 3 phase system). So when you were hitting 255A motor, your battery “only” delivered theoretically a maximum of ~180A, most likely even up to 20% less due to the power factor and the inaccuracy of the estimation of the battery current by phase shunts.
So yeah with 16S11P 25R the sag to 57V is quite realistic and with around 150A your estimation of 8kW is really good.
For better insight you should really log some data.
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54km/h is already fast you beat my record 
Drag of you motor pod becomes more&more imprtant, however with 2 wing setup whereas 1 wing is in the air at high speeds help to increase speed…Tried it and got faster with same motor power…
Best i think is use thin race foil as lower foil and a slowflying profile on top of the mast, or just use race foil wing accelerate to 30km/h then start foiling and hit the 60km/h 
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Great news Do you have any picture of your dual wing foil ? Can you quantify the speed gain and link it to the front wing surface decrease ??
Would you have these data :
1- speed gain and amp decrease at upper wing take-off
2- speed loss and amp increase when the upper wing touches the water.
In our quest to decrease the pod drag, we could start by filling in the screw holes
