yes, it will power up the esc, so if you have your remote on and accidentally hit the brakes, it will brake
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Thats actually nice, because i will never have det remote off - either 4wd or rwd, using the same remote.
So if the only âdownsideâ is that the vesc is still able to brake, it is not a downside at all 
But you are sure that the vesc will be powered by the generated current from the free rolling motors?
I think I owe you a picture of the monster:
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Not necessarily wrong but the motor only âgenerates powerâ when you have a full closed current loop.
If you are free wheeling a motor even at high speeds it is not a generator! In order for it to âgenerateâ power you have to trade kinetic energy for electrical. If you are coasting, âgenerating power without brakingâ, then you win the Nobel prize for disproving basic laws of physics. Free energy!!!
Now with a powered off VESC you may or may not have a connection for the phases (FET gates are indeterminate states) and if at some point you are in a braking situation then yep Now itâs a generator.
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SoâŚExplain to me then, @FredSaberhagen How did my motor wires melt and phase out while riding downhill with the board off?
Second time, explain to me how my mosfets melted and phased out my motor while being towed with the board off?
I never said anything about creating free energyâŚRolling downhill is the equivalent of the wind spinning a turbine. Something from something.
The motors do generate power from spinning. They are generators.
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But the motor does generate energy while coasting. It generates power while on the throttle too⌠just not as much as it consumes. Are you talking about a motor with the phase wires disconnected?
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Itâs because when your vesc was turned off (no current sink output from drv pulling their gates low - all fets are nfet in vesc) the gates probably floated (they call it shoot-thru) and connected two of your phase wires to each other. Youll get the same result if you connect two phase wires and tow your board 
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Yes if youre driving it then a current loop exists and it does have a back emf (why we need 14S) to beat that. If the vesc is on then it can effectively disconnect and float the phase wires and you dont pay a inertial momentum penalty. Nothing generated (to generate you would have had to put in kinetic energy to trade for coulombs)
To test this - what would happen to a motor with dangling phase wires connected to nothing - if you spun it up really fast? Would it explode from all the energy âgeneratedâ with no where to put it (it would have to dissipate it as heat?)
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Iâve thought of this scenario too. Not sure. Heat builds up though to a point where things will melt. That is how my motor phased out . The power created had no where to go.
Iâm not the only one this has happened to.
Fred is right.
Motors donât make energy by just spinning. âEnergyâ aka âelectrical energyâ ie Watts requires voltage and current. When a motor is being used as a generator, with no load, it creates voltage based on its kV and rpm. Ie it makes voltage with no current as there is no load.
Once you add load such as the vesc with nfets the load (even though small) is powering the vesc, the vesc boots up and keeps sync with the motor, when your towing you speed up and slow down, slowing down and the voltage drops below minimum input, vesc at low speed goes though what is called âelectrical brown outâ where the voltage is enough to keep the mechanism on, but to low of voltage to function properly. Possibly leaving the vesc out of sync with the motor, shorting braking and causing heat.
Solutions -disconnect the belt -unplug or switch cut the phase wires -ride with the board plugged -design an esc?
Why would you need to do any of those things if no power/heat is created?
A bottleneck is a bottleneck.
And outrunners most definitely create energy by spinning.
If the vesc is connected refer to brown out section of post.
If the motors phases are disconnected no load is there just voltage at rpm
The only way you could have melted if the phases were disconnected is if there was already a short in the phases from the enamel melting off.
Nope! 10 characters HEAT.
Lol heat doesnât appear from thin air. Magnetic flux of a no load motor(generator)âŚmaking that much heat I doubt too.
So please explain where the heat is coming from.
I guess if we make a hypothetical argument we can say anything we want but the fact remains the motor will generate power and turn the vesc on if it is in circuit with a soft switch. Thatâs why we can use our brakes if we are coasting with the board switched off.
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Seriously? The heat comes from energy created by the motor spinning. That energy with no where to go creates heat. Heat melts copper and mosfets.
Iâve seen it happen 2 times.
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And @chaka this analogy will make more sense:
Imagine you are breathing though a big straw. In, out, repeat, in the air. Not that hard.
This is what happens in your motor as a magnet passes a pole. Magnetic field in/out
Now, itâs easy to do in the air. But if you place the straw in a bucket of water it becomes very hard. You still have to breathe in and out ⌠but now youâre moving a mass of water up and down the straw.
That water sloshing back and forth has friction in the straw. Friction = heat of course
So take away the pool of water/phase connection and no work no friction no heat
When you say " I have brakes when rolling powered off" then you are not powered off 
like compression starting a car I guess. Only way to stop that would be to have a source actively sinking all 6 of your FETs at all times.
Psycho you are a little bit right in that those big outrunner magnets have a little bit of resistance to them ⌠flipping that mag field back and forth does induce eddy currents and lose a little energy to heat!
This mellow mitigated by stacking up loads of tiny tiny magnets insulated from each other so eddy current loops must be very small. If you have a cheap motor with one big long magnet you will pay more % in eddy currents for sure (besides friction, this the only reason cogging isnât truly energy neutral)
Iâm not sure you are understanding. This is a commonly observed behavior of a well designed board. If it is switched off and you roll down a hill it will turn on, simple as that. Thanks for the explanation though, I have a pretty good understanding of how motors work But your analogy will definitely help others around here.
Maybe you are arguing what happens in a broken circuit, i.e. no soft switch. If that is the case you wont here me arguing anything⌠I have my regular kick push boards for that!
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So ur saying even w batteries connected but board not turnrf on if going at slow speeds as the vesc turns on and off thatâs a brownout and potential damage ?
Thank you for all your in-depth answers guys. It is interesting reading stuff.
I think, however, I found a completely different solution. I put a switch to disconnect the supply to the two front axle remote receivers, so that I can drive rwd with the two front controllers powered on.
They Will not react to the remote input since they dont receive a signal from the remote control, but the vescs are still on controlling the motors.
What do you think about solution?
Let me know if i have to explain it in another way (and no - english is not my first language) 
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@Hummie If your batteries are DISCONNECTED, ie board not turned on, with or without a soft switch(loop key or antispark), if the power to the VESC is solely from the motor, your VESC will be going through waves of brownouts yes.
If your board is turned on and the VESCâs are receiving power from the battery, the components will be run at proper operating voltages, and not be going through waves of voltage brownouts
@DK-Odense that would probably be the best/easiest solution, leaving the escâs powered with a disconnect switch for the PPM signal - just make sure you have your failsafe setup properly and iâd probably suggest unchecking limit erpm with negative torque for the front wheelsâŚ
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