Do bigger motors deliver more torque at the same motor current?

“high” lmao okay

Yes it’s possible the 6355’s saturated before reaching max current applied? Not 100% sure

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this was close to a year ago
gimme a break

no idea how motors work so i would have no clue how to tell or know whether that happened

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lol I’m messing around. I do usually roughly remember though

On my BKB motors they squealed at 55 motor amps and stalled out

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Someone in a YouTube comment said that all the best DIYers use 6384 and bigger motors now.

That’s why I threw all my 6374 motors in the trash.

More millimeters, moar tork.

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so say you had flipsky 6374s at 100A. and upgraded to 63100s thought it felt like more torque, even when the 63100 was lowered to 80A? this is one of the anecdotes.

how would you explain that?

just real KV differences vs stated KV differences? which is what I suspect?
or can something like the 6374 be oversaturated and performing worse than it would have it was at 80A?

is it possible that running the 6374 at 100A over saturates it and it somehow does worse than it would have at 80A (it’s rating).

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Bigger motors usually also produce a higher torque * Kv product i.e. power, before they start saturating and/or overheating.

A motor saturates when more current =/= more torque.

A motor’s figure of merit is its Kv * Resistance product.

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6374 190kv typically saturate at 60A.

No, unless youre using vesc, because vesc torque efficiency drops exponentially with current due to poor tracking in sensorless with increasing current. This is the cause of that doggone torque pickup effect everyone gets.

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torque pickup effect?

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It’s a well known thing where you get more torque as you speed up with vesc despite the same throttle setting. It was really bad on older versions where you basically had no startup torque.

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tx.

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From the electronics standpoint, I’d only go for bigger motors to have more thermal mass and thus better performance due to lower temps/thermal resistance offset at high heat. If there’s space on the trucks, why not go for bigger cans… usually the price jump isn’t that big.

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While accelerating, at first acceleration will be limited by the motor current setting then at higher speeds acceleration will be limited by the battery current setting.

Acceleration with a larger, same kv motor (assuming it has lower electrical resistance), will be the same on both motors at lower speeds while you’re limited by the motor current setting, but at higher speeds when you are limited by the battery current setting, the larger motor will get better acceleration, because it’s receiving more motor current for the same battery current with the same settings.

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I am not an electrical engineer yet, but from my understanding, I don’t think that would be the case, as the control mode everyone uses on the VESC is current control… Current can be controlled, by changing the resistance of the system. With a motor of 50 mOhm resistance, at 12S full charge, 1000A could flow through the motor if the ESC had zero resistance. I am not sure how exactly current control works (how exactly the ESC changes resistance) but I don’t think the lower resistance of a larger motor could help in any meaningful way.

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Well if both motors receive the same motor current, the lower resistance motor will be drawing less battery current. That also means for the same battery current, the lower resistance motor will receive more motor current and so have greater acceleration.

The esc doesn’t change the resistance it changes the voltage.

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Ah, right, that makes sense.

But if both motors are the same KV running at the same RPM then you would expect them to be driven at the same duty cycle right?

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No, the lower resistance motor will have lower duty cycle at the same kv, motor current and rpm.

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Lower resistance motor will need less voltage to hit the target current. This will result in lower duty cycle. Which I guess in theory results in less battery current. Seems to make sense.

“For the same battery current” so what your saying here is if you increase the battery current (which increases total power and therefore increases motor current) then you will have better acceleration. Yes, of course if you use more power you will get better acceleration.

This is not proving that bigger motor give you more acceleration at the same motor current, it’s just showing that low resistance motor is more efficient.

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Right, you won’t get more acceleration for the same motor current, but you will get more acceleration for the same battery current, and at higher speeds you’re actually being limited by the battery current setting not the motor current setting, so it will essentially feel like the bigger motor gives more acceleration above a certain speed with the same settings.

Honestly, anyone that believes that bigger motors give you more power is a fucking idiot. What you are essentially claiming is that you have discovered free energy. Ridiculous.

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