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Old 09-30-2024 | 07:21 AM
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Default ? On motors and timing.

So I have two different brands of motors both 21.5t. Both top out at about the same rpm. But one brand is tuned to 52 degrees of timing the other is at 43 degrees of timing. Same amp draw. Will the one with lower timing have more torque?
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Old 09-30-2024 | 09:17 AM
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Great question, I’m curious to hear what people have to say. I think this might be best in the radio / electronics forum forum though.
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Old 09-30-2024 | 12:49 PM
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Originally Posted by RubberMatt
So I have two different brands of motors both 21.5t. Both top out at about the same rpm. But one brand is tuned to 52 degrees of timing the other is at 43 degrees of timing. Same amp draw. Will the one with lower timing have more torque?

The torque would depend on the overall build of the motor. What motors are they, what is the RPM, and what is the current draw?
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Old 09-30-2024 | 01:11 PM
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Originally Posted by RubberMatt
So I have two different brands of motors both 21.5t. Both top out at about the same rpm. But one brand is tuned to 52 degrees of timing the other is at 43 degrees of timing. Same amp draw. Will the one with lower timing have more torque?
What amp draw do you have them set at? I always try to do a little over 5A on a 17.5, but not sure where to start with a 21.5.
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Old 09-30-2024 | 01:16 PM
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Originally Posted by ThisIsRDG
What amp draw do you have them set at? I always try to do a little over 5A on a 17.5, but not sure where to start with a 21.5.
amp draw on the 53 degree motor is 6.0 and the 43 degree motor is 5.8 amps both motors are within 600 rpm of each other.
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Old 09-30-2024 | 01:18 PM
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Originally Posted by OffRoadJunkie
The torque would depend on the overall build of the motor. What motors are they, what is the RPM, and what is the current draw?
I wanted to keeps the brands out of the conversation. I was trying to cut down on the fanboy answers.
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Old 09-30-2024 | 01:32 PM
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Originally Posted by RubberMatt
I wanted to keeps the brands out of the conversation. I was trying to cut down on the fanboy answers.

Trust me. I'm not a fan boy. I make videos about testing and comparing motors. What machine did you use to get your numbers?
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Old 09-30-2024 | 01:44 PM
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It's at home but I believe it is the sky rc version. I reshimmed the motors and got the timing alot closer. The 43 degree motor is brand new and I installed ceramic bearings and titanium screws.
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Old 09-30-2024 | 02:15 PM
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Originally Posted by RubberMatt
It's at home but I believe it is the sky rc version. I reshimmed the motors and got the timing alot closer. The 43 degree motor is brand new and I installed ceramic bearings and titanium screws.

Which one had the biggest amp jump from being one or two degrees down? The biggest difference would be the kV. The problem with the Sky RC doesn't have a power regulator, so each motor was seeing a different voltage. Either way, it is almost impossible to tell which one has the most torque by looking at the RPM, current, and kV. Knowing the strength of the rotor would help break the tie. Also, this is the exact reason why WMH Racing made the Load Master.

One thing you could do is, run the tests while the motor is installed in your car. The car's drivetrain will add resistance. The car that has the less current draw will be the one with the most torque.
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Old 09-30-2024 | 02:21 PM
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So on paper timing will not mean anything. So if thr rpm voltage and amp draw are the same they should be even. the torque is made up in the measurements on the rotor. And I think that is meessured in Gass if I remember correctly.
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Old 09-30-2024 | 02:34 PM
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Originally Posted by RubberMatt
So on paper timing will not mean anything. So if thr rpm voltage and amp draw are the same they should be even. the torque is made up in the measurements on the rotor. And I think that is meessured in Gass if I remember correctly.
When comparing motors, timing is not a good way to do it. It's like having two engines with the same hp and RPM when measured on a stand. You will not be able to tell the difference in torque unless you put a load on them. It's all about how they are built, internally. Have you seen any of my videos? I have motors that have the same amperage and over a thousand RPM difference between them. However, as soon as I add a load, the difference becomes a lot smaller with the amperage also greatly changing.

Here is a video where I explain a little more about the performance differences.

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Old 09-30-2024 | 04:16 PM
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Originally Posted by RubberMatt
I wanted to keeps the brands out of the conversation. I was trying to cut down on the fanboy answers.
Problem is that you can't know torque without actually measuring it or at least knowing the rotor strength.
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Old 10-01-2024 | 01:16 AM
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Originally Posted by gigaplex
Problem is that you can't know torque without actually measuring it or at least knowing the rotor strength.
And rotor diameter
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Old 10-01-2024 | 07:21 AM
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Originally Posted by gigaplex
Problem is that you can't know torque without actually measuring it or at least knowing the rotor strength.

I have used an EMF Meter similar to this to read rotor strength:

Amazon Amazon


I physically removed the rotor and slowly rotated the rotor as close to the meter and had it lock onto the max reading.


I found disparity between rotors of the same brand and learned to cherry pick the stronger rotors using the EMF Meter

Note that these cheaper EMF Meters can only read 540 sized rotors, I tried it on a 550 SCT motor and it maxed out
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Old 10-01-2024 | 09:03 AM
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A strong rotor is a good place to start, but it doesn't always mean the motor will have a lot of torque. The HW G4r, I just recently tested, had a 1765 rotor. That is very strong. However, under a load, it didn't fair very well with torque.
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