<p>Like most things, it depends on how you treat it.</p>

<p>As far as I know, you should never need to worry about a brushless motor wearing out, especially for our purposes where we will likely demolish them before they have a chance to wear out.</p>

<p>You do have to watch out for the bearings and magnets, however.</p>

<p>With the bearings, like any mechanical component, they will eventually wear down, however this will likely not be for a long time. It is still a consideration, though.</p>

<p>You also have to watch out for the magnets.</p>

<p>Under normal circumstances, the magnets are fine to last a long time, however excessive heat can eventually demagnetise them, leading to reduced performance and eventually the motor not producing enough power for us to use.</p>

<p>If anyone has any other ideas or wants to correct me, please do!</p>

CC BY-SA 4.0
2020-04-21T11:26:22.560Z
Good answer. I would add that an easy way to check for demagnetization is to check the no-load RPMs. You'll want to check the no-load RPMs when. You first get your motors by running them to full throttle at a defined voltage, and keep a record. If you have a bench supply and are using a flight control firmware that supports rpm logging via ESC telemetry this is fairly straight forward. Then just check every so often. If the no-load RPMs are increasing, you're losing magnetic field strength due to heat damage.
QuadMcFly
CC BY-SA 4.0
2020-04-21T11:29:10.007Z
@QuadMcFly excellent idea - though is this supported on ESC firmwares other than BLHeli_32? If so I’d be very interested in seeing how to do this.
Drones and Whatnot
CC BY-SA 4.0
2020-04-21T11:34:10.247Z
Yes, it would work on KISS ESCs as well, as they also support RPM telemetry. It doesn't need to be extremely low latency just sustained. I believe the VESC project also supports some sort of RPM monitoring, which is used by some larger drones.
QuadMcFly
CC BY-SA 4.0
2020-04-21T11:36:56.020Z
@QuadMcFly good to know - thanks!
Drones and Whatnot
CC BY-SA 4.0
2020-04-21T09:15:18.083Z
2020-04-21T11:21:37.087Z
2020-04-21T11:21:37.087Z
Drones and Whatnot
<p>The brushes wear out in brushed motors and their performance decreases until they stop working, but brushless motors have fewer parts in contact and thus don't wear out nearly as fast. </p>

<p>Does the performance of a brushless motor decrease over time or does its performance remain practically the same throughout its life?</p>

<brushless-motors><comparison><performance>
Does the performance of a brushless motor decrease over time?
Jacob B
# Does the performance of a brushless motor decrease over time?

(Asked by: username_0 on 2020-04-21)

The brushes wear out in brushed motors and their performance decreases until they stop working, but brushless motors have fewer parts in contact and thus don't wear out nearly as fast.

Does the performance of a brushless motor decrease over time or does its performance remain practically the same throughout its life?

**Tags:** brushless-motors, comparison, performance


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## 1 answers

### Answer by username_1 on 2020-04-21. Score: 6 | Accepted answer

Like most things, it depends on how you treat it.

As far as I know, you should never need to worry about a brushless motor wearing out, especially for our purposes where we will likely demolish them before they have a chance to wear out.

You do have to watch out for the bearings and magnets, however.

With the bearings, like any mechanical component, they will eventually wear down, however this will likely not be for a long time. It is still a consideration, though.

You also have to watch out for the magnets.

Under normal circumstances, the magnets are fine to last a long time, however excessive heat can eventually demagnetise them, leading to reduced performance and eventually the motor not producing enough power for us to use.

If anyone has any other ideas or wants to correct me, please do!

> **Comments:**
> **username_2**: Good answer. I would add that an easy way to check for demagnetization is to check the no-load RPMs. You'll want to check the no-load RPMs when. You first get your motors by running them to full throttle at a defined voltage, and keep a record. If you have a bench supply and are using a flight control firmware that supports rpm logging via ESC telemetry this is fairly straight forward. Then just check every so often. If the no-load RPMs are increasing, you're losing magnetic field strength due to heat damage.  
> **username_1**: @username_2 excellent idea - though is this supported on ESC firmwares other than BLHeli_32? If so I’d be very interested in seeing how to do this.  
> **username_2**: Yes, it would work on KISS ESCs as well, as they also support RPM telemetry. It doesn't need to be extremely low latency just sustained. I believe the VESC project also supports some sort of RPM monitoring, which is used by some larger username_1.  
> **username_1**: @username_2 good to know - thanks!  

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