Try dropping motor amps to 60 and see if that changes anything. Also 75 for battery is waaaaaaaaaay too high, try dropping to 20 or 30. Pinging @b264 and @BenjaminF for guidance because it’s been a while since I programmed an ESC
My battery should be able to handle it. n2.1 LG pouch cells are rated for 120a continuous so that shouldn’t be an issue.
That motor doesn’t appear to have any sensors at all, either hall or temperature. If it’s the same one, then your thermal throttling isn’t coming from the motor, but rather the vesc itself.
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Keep in mind that often this is more marketing-department-vomit than actual science.
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75A “battery max” is really, really high and the very first troubleshooting step I’d try, is lower this to 25A and see if the problem persists. If not, then raise it 5A at a time until problems happen, then back off a tad.
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when the motor reached 70c, the vesc was only at 45c. I used an infrared thermometer to check the motor.
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75 battery amps would only be drawn at very high speed right? At 25mph, I was only drawing around 750 watts from the battery.
Does your motor have sensors? (a set of smaller wires other than the three big ones?)
If so, then the vesc could definitely be thermal throttling.
If not, then the vesc has no way at all to know that the motor is hot or cold. If the motor was losing power it may have actually reached a high enough internal temperature to begin to permanently damage the magnets.
With an external temp of 70, the internal temp could easily be above 80, and that’s the temperature at which neodymium magnets begin to lose their strength, depending on the grade.
What I’m trying to say is, you probably need to either cool your motor (or vesc) better, or run less power through it.
Inrunner motors often have a significantly lower inductance than outrunners of a comparable power or kv, which may be contributing to the heating problem.
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Are you sure that your motor is rated for that amount of voltage?
Also, by doubling your voltage and keeping your amperage the same, you are also doubling your wattage.
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And doubling increasing your power losses, even assuming the efficiency stays the same, which is probably not the case.
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Motor has no sensors.
I should have been more specific. I did not notice the motor thermal throttling on its own. I was referring to the winding temp that was getting close to damaging the motor. Every 1 minute 30 seconds, I stopped to record the internal temperature. The motor has exposed windings so I was able to record the core temperature. After the third time I tested the temp, I knew to stop before damaging the motor.
So increased watts increase power losses, not current specifically?
Man, if I didn’t already have “Enforcer of Cunningham’s Law” as my title, that would definitely be in the running 
Increased voltage means increased RPM, both electronic and mechanical, both of which generate more heat. Viscous friction of the rotor with the air at 50K RPM, iron losses, copper losses, they all add up.
Increased voltage also means the vesc has to work harder at partial duty cycles to control that higher voltage when feeding it to the motor.
Most applications for larger high powered inrunners either are short bursts/not full power all the time (rc cars), or have integrated cooling (RC boats and e-foils/e-surf).
Inrunners don’t have the advantage of a big spinning bell on the outside to get the air moving around the stator. They’re easier to cool directly through conduction though. Look into heat sinks or water jackets.
Both tests were done at max 95% duty cycle the majority of the time except for when i stopped to check motor temps.
That’s a decent option, but only a bandaid. It doesn’t really fix the source of the issue.
Doesn’t moestooge run his inrunners at 8s, 200a with no heatsink while riding balls to the walls up hills with his motors only getting warm to the touch? I mean, my motor can cook an egg just by riding at running speed on flat roads. Not exactly stressing it much.
Tomorrow I will lower motor and battery max and change the gearing a bit to see if that has any affect on temps.
Anyone know where I can buy some 12s and 10s Daly’s with quick shipping to the US? Kevin is out, and I need them ASAP.
I should have an unused 12S Daly somewhere. Send me a PM if interested…
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Hi guys, looking for a ebike rear wheel hub motor. Could you point me out to some good vendors in Europe? Thanks
Maybe you can try that one
I’ve bought my Cycle Satiator there
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