I’ll order two belts from both sites, wich ever last longest and or arrives first is what ill countinue to buy from thanks man.
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Great testing method. Empirical data has always served me best.
Hi
I have some issues with my first setup. The motor sometimes makes some noise and the belts sometimes get stuck. I have not ridden the board yet.
Please take a look at these two short videos.
Such symptoms occur when one of the motor’s three cables is in contact. Try to prevent the cables from touching each other.
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I run Flipsky 6.6 with dual 6374 motors, now during summer the weather is really hot, motors don’t get too hot to touch but I don’t have a way to monitor my vesc, can it go into thermal shutdown and trow me off?
Side question, can I run 2 uart devices on one vesc? Eg photon remote and trampa dongle?
The vesc has a soft thermal protection feature - As it nears the danger zone, it will begin reducing its power output until it reaches equilibrium or the maximum allowable temperature, whichever comes first. TLDR it will slow down gradually as it overheats, not throw you off.
WOW!!! You are right. Thank god I don’t need to send these motors back Thanks
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hey im gonna buy an ownboard and save up to make a 4wd kaly nyc board are there any problems that tend to happen with 4wd boards i should know about before i start saving up
Unless you’re trying to seriously off road or race, start with 2wd. It’s simple to add another 2 motors and a controller later on and will get you rolling sooner.
I blast up hills with a 2wd 10s5p samsung 30q battery. I also off road a good amount. If I ever get hardcore into off road or racing, maybe I’d consider it. Drains your battery much faster running 4 motors.
Example of 2wd crushing through a field
ok thanks man that takes about 4000 off my build
Is it possible to apply 12S (50 Volts) to the motor immediately from 0 RPM or voltage increases with increasing RPM only?
I’m gonna split this into two possible permutations:
Q1: Is it physically possible to to apply 12S (50 Volts) to the motor immediately from 0 RPM?
A1: Yes, but it will cause a ridiculous initial current draw due to the low resistance of the windings, possibly damaging the motor and/or the controller and/or the battery or BMS.
Q2: Can a Vesc do the above?
A2: I don’t know, but I don’t think you’d get THAT much more performance, considering the risk to your hardware. Also, with the ridiculous current, you’d saturate your stator (Once saturated, you get very little to no benefit to increased amperage).
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I incorrectly formulated the question, I don’t gonna make changes, just wanna understand how voltage affects torque from 0 mph. But as I understand from your answer, the voltage grows gradually until the maximum speed is reached, right? I bring the question to whether the torque will change at low revs when using different 8S 10S or 12S batteries.
In other words, whether the torque/acceleration will change at low RPM when using different batteries 6S / 12S / 18S with the same current?
Voltage does not directly affect torque. Torque in an electric motor is caused by the interaction of magnetic fields, at least one of which is from an electromagnet. The strength of the interaction (and thus torque) is proportional to the strength of the fields, and the strength of an electromagnet is a function of the number of turns of wire, times the number of amps.
TLDR, more amps=more torque, until you saturate the steel in the stator. Voltage is only there to push the electrons around, generating the current.
The Vesc is usually in current-limiting mode, where it adjusts its output voltage to maintain the output current at or below the maximum set value. When a motor is stopped, the only thing stopping it from drawing infinite current is its own internal resistance (measured in miliohms) and the similarly low internal resistances of the VESC, BMS, wiring, and battery. Thus at low speed if you measure the voltage and current output of the VESC, if it’s set at 50 motor amps and you floor it, it will shove 50 amps through the motor, but only like 8 volts. This is because any higher voltage would cause the motor to pass more than 50 amps.
This changes at higher speeds, due to a phenomenon called back-EMF, or generated voltage. As the motor spins, it behaves as a generator, producing a voltage that opposes the input. At some point the back-EMF and the input voltage match each other, and this is the point where the motor will not spin any faster - its maximum speed. This is why esk8 and other vehicles powered by BLDC motors have a “hard limit” on top speed - it’s not about available power like it is in a car, rather it’s the point where the motor just will not spin faster because that would cause it to generate electricity rather than consume it.
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An esk8 with a 6s battery, and an esk8 with a 12s battery (and all other hardware and settings identical) will accelerate the same from a dead stop. The 12s will continue accelerating for longer, and reach a higher top speed, but the 6s will launch just as hard.
This is the same thing that your battery current setting affects - not how hard you accelerate initally, but for how long that acceleration persists before tailing off.
Think of motor current as torque, and battery current as maximum horsepower. Raising your maximum horsepower won’t necessarily increase your torque at launch, but you’ll still win the race because you can keep accelerating longer.
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It is very useful to know, thank you!
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Glad to help. It’s a common misconception and not a super intuitive answer, so I try to go into extra detail when explaining it. 
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The thing I can’t figure out in right now is resistance.
We have Ohm’s law: current = voltage / resistance
If VESC can handle 100A, then motor with winding resistance of 0.05 ohm can start working at 5 volts (it gives us 500W power from 0 mph). Then does the resistance start to grow slowly, and the voltage increases accordingly up to max RPM?
However it means the higher motor windings resistance, the more torque. This sounds logical, considering that motors with lower KV have more windings and resistance, and give more torque, but what if its high resistance is not related to the KV but to low motor quality?
I feel like I’ve written complete nonsense 
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The resistance of the motor doesn’t increase, but the back-EMF (generated voltage) opposes the battery voltage more and more as speed increases, which makes the motor behave as if its resistance is changing.
The resistance is not directly related to torque or KV, merely a side effect. As I mentioned above, the strength of the magnetic field is proportional to the current times the number of turns. A lower KV motor (more torque) has more turns, and thus produces stronger magnetic fields per amp. But because wire has resistance, more turns means longer wire, which has a higher resistance.
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