Brushless Motors Failing

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3 of your motors have failed. No one is saying that you failed your motors, which is far too deeply philosophical for this thread 😝🤣

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The kuron 825 was binding. I opened it up, cleaned it out, and it now lives in my maxx slash. So only two motors are dead. I caught the kuron before I fully killed it and am making changes one at a time to reduce the chances of more untimely failures.
 
If 160F is deemed acceptable by the manufacturer it should handle 160 indefinitely? Regardless, I think most all my electric motors have seen 180 by now, some 230, Kaiju with a $40 Surpass 4068. All still going. I have two 6 pole motors, a Ten Shock 802L 4274 2200kv and a Turnigy Track Star 4268 2560kv. The 802L is nearly 15 years old, Track Star about 10. Neither has any wrap left on the rotor, the 802L just lost a bearing on the output end, upon inspection it seems the rows of magnets are no longer tight or aligned. New bearing installed, see what it does, LOL. Both have been outstanding performers for me, I might even buy anothor 802L TBH. The Turnigy motor is now obsolete, the two look identical inside and out. Bet they came from the same sweat shop!😆
Before installing and logging a temperature sensor on the motors, I would have told you my motors were not going above 130F based on the fact I could put my finger on the can and hold it there for 5 seconds. That same motor logs at 180F. I am getting 100 6s runs out of my maxx slash like that.

I think a lot of folks are running well past 180F without knowing it and without huge reliability issues. HW themselves never states an operating range, just that 190-200F is too much.

I have less to lose trying to keep temps lower than 160F. Same with keeping dirt from getting inside the motor. The HW is fully sealed, so that is easy. The stock corally motors are not and the factory does not block off the unused mounting screw holes.
 
All this being said - I'm looking through the information in the manual for my XR10 Pro G3 and V10 G3 5.5T motor - the temperatures are not recommended above 212° - so it really depends on the material used and the design.

Personally, I'm sceptical about such high temperature claims because rare earth magnets lose flux if they are repeatedly heated up. The hotter they get, the more flux is lost.

So ultimately, even if your motor hasn't 'failed' it will get less efficient and lose punch as a result. These motors are the better part of a 100 sterlings, so you really don't want them to go weak before they're due.
 
Before installing and logging a temperature sensor on the motors, I would have told you my motors were not going above 130F based on the fact I could put my finger on the can and hold it there for 5 seconds. That same motor logs at 180F. I am getting 100 6s runs out of my maxx slash like that.

I think a lot of folks are running well past 180F without knowing it and without huge reliability issues. HW themselves never states an operating range, just that 190-200F is too much.

I have less to lose trying to keep temps lower than 160F. Same with keeping dirt from getting inside the motor. The HW is fully sealed, so that is easy. The stock corally motors are not and the factory does not block off the unused mounting screw holes.
My 825 has been running fine since 2021 and has no sign of dirt ingress. 🤔
 
All this being said - I'm looking through the information in the manual for my XR10 Pro G3 and V10 G3 5.5T motor - the temperatures are not recommended above 212° - so it really depends on the material used and the design.

Personally, I'm sceptical about such high temperature claims because rare earth magnets lose flux if they are repeatedly heated up. The hotter they get, the more flux is lost.

So ultimately, even if your motor hasn't 'failed' it will get less efficient and lose punch as a result. These motors are the better part of a 100 sterlings, so you really don't want them to go weak before they're due.
Yeah, take my readings with a grain of salt since I'm using a temp gun from China (Harbor) Freight, who knows how accurate that is.
"They" say internal motor temps are often quite a bit higher than external. True? IDK. I do try to make sure my motors stay under 160 whenever feasible, some rigs I won't even run during the summer months because of the temps, others I just say F it, if it cooks, it was fun while it lasted.. such as the $40 Surpass I put in the Kaiju a few years back. It's paid for itself as far as I'm concerned. Not looking to ruin it, but whatever will be..
I buy cheap components intentionally, partly cuz I'm cheap, but also because I'm chronically broke. I think the Ten Shock I mentioned earlier is the most expensive rc motor I ever bought, I paid around $190 for the combo back in 2011. HW Xerun 150a with motor.. ;)
 
I was gifted a TRX UDR for fathers day this year, yes, believe it or not the UDR was MY choice.. and yes, I have regrets LOL. But anyway, the UDR motor is pretty well encapsulated in the plastic "inverted tub chassis". Doesn't get much airflow at all. Box stock on 6s I was getting motor temp readings at the back (only exposed portion) of the motor can of 180 after about 6 minutes of run time at 80F ambient temps.. wow, how is YT not completely loaded with vids of folks smoking their UDR motors? IDK. Perhaps cuz the motors are indeed more heat tolerant than most think?
Anywho, I decided the UDR motor needed some ventilation, all I had on hand for fans at the time were some WinSinn branded 50x10 dual BB units (5 for $18 on Amazon).. So I uh removed the body, cage (partially) and the driver figure tray, and grabbed my 2" hole saw. Punched a hole through the plastic tub (inverted chassis) from the top down. Mounted and wired up the fan and reassembled everything. Now with with a $3.60 fan the UDR never crests 145F even in 90F ambient temps! Success! For the record I have dubbed the UDR as Humpty Dumpty as it's broken more than running.. LOL.
I also use Winsinn fans in pretty much all my rigs. Yeah they're weak, but also come in 5 packs for dirt cheap.👌
 
If you run in terrain with fine sand your motor bearings will become gritty and stop turning at same point. Resulting in super hot motor and bearings falling apart at some time completely destroying your motor in worst case scenario. Been there.
I had a Dusty shroud and it certainly helps, but what works also for me is (I no longer run a Dusty shroud)
1. Putting grub screws in the motor holes that are not used
2. An o-ring on the motor shaft in the motor shaft opening
3. Most important of the three, so I guess I should have put it at no.1, replace the motor bearings with aftermarket ones. Rubber shielded bearings that can also handle high rpm’s are harder to find than metal shielded bearings. All stock motor bearings are pretty bad; even the ‘high rpm Japanese made’, according to HW website, ones in Hobbywing motors, which state ‘Singapore’ if you open the motor.🤦‍♂️
 
even the ‘high rpm Japanese made’, according to HW website, ones in Hobbywing motors, which state ‘Singapore’ if you open the motor.
I've noticed that too.. NOT made in Japan! Too bad, the Japanese make some of the best precision stuff in the world. I opt for Japanese manufactured bearings whenever possible.
 
If you run in terrain with fine sand your motor bearings will become gritty and stop turning at same point. Resulting in super hot motor and bearings falling apart at some time completely destroying your motor in worst case scenario. Been there.
I had a Dusty shroud and it certainly helps, but what works also for me is (I no longer run a Dusty shroud)
1. Putting grub screws in the motor holes that are not used
2. An o-ring on the motor shaft in the motor shaft opening
3. Most important of the three, so I guess I should have put it at no.1, replace the motor bearings with aftermarket ones. Rubber shielded bearings that can also handle high rpm’s are harder to find than metal shielded bearings. All stock motor bearings are pretty bad; even the ‘high rpm Japanese made’, according to HW website, ones in Hobbywing motors, which state ‘Singapore’ if you open the motor.🤦‍♂️

Good tip on the o ring on motor shaft. I was told to be careful when blowing air to clean the car, don’t blow towards the motor shaft. So this can’t hurt.

I’ve been trying to find good bearings. Found some Japanese ezo bearings from Grainger but they are not reliable. I can’t find anything rated above 50k rpm.
 
Good tip on the o ring on motor shaft. I was told to be careful when blowing air to clean the car, don’t blow towards the motor shaft. So this can’t hurt.

I’ve been trying to find good bearings. Found some Japanese ezo bearings from Grainger but they are not reliable. I can’t find anything rated above 50k rpm.
50k should be plenty. Only a handful of rc motors are rated to spin over 50k.
 
I was gifted a TRX UDR for fathers day this year, yes, believe it or not the UDR was MY choice.. and yes, I have regrets LOL. But anyway, the UDR motor is pretty well encapsulated in the plastic "inverted tub chassis". Doesn't get much airflow at all. Box stock on 6s I was getting motor temp readings at the back (only exposed portion) of the motor can of 180 after about 6 minutes of run time at 80F ambient temps.. wow, how is YT not completely loaded with vids of folks smoking their UDR motors? IDK. Perhaps cuz the motors are indeed more heat tolerant than most think?
Anywho, I decided the UDR motor needed some ventilation, all I had on hand for fans at the time were some WinSinn branded 50x10 dual BB units (5 for $18 on Amazon).. So I uh removed the body, cage (partially) and the driver figure tray, and grabbed my 2" hole saw. Punched a hole through the plastic tub (inverted chassis) from the top down. Mounted and wired up the fan and reassembled everything. Now with with a $3.60 fan the UDR never crests 145F even in 90F ambient temps! Success! For the record I have dubbed the UDR as Humpty Dumpty as it's broken more than running.. LOL.
I also use Winsinn fans in pretty much all my rigs. Yeah they're weak, but also come in 5 packs for dirt cheap.👌
My maxx slash has a similar motor and I have ran that way to hot just like you without any drop in power. The only failure to it has been directly my fault.
 
50k should be plenty. Only a handful of rc motors are rated to spin over 50k.
The hw 2250kv, grizzly 2100kv, kuron 2050kv, and Traxxas 2000kv motors all have seen above 50k rpm on 6s though? The Traxxas has arguably seen the most abuse but objectively most time above 50k rpm though. I keep it pinned for the duration of the run. The bearings I can find are only rated for 36k rpm.
 
The hw 2250kv, grizzly 2100kv, kuron 2050kv, and Traxxas 2000kv motors all have seen above 50k rpm on 6s though? The Traxxas has arguably seen the most abuse but objectively most time above 50k rpm though. I keep it pinned for the duration of the run. The bearings I can find are only rated for 36k rpm.
If we do the math, a 2200kv 6s motor spins 48840RPM theoretically on 6s. At 3.7v per cell x 6s=22.2v, x 2200kv =48840. 2200kv really is the upper limit I would consider for one of my 6s bashers. There are motors rated higher, Castle often rates their motors to 60k.
 
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My maxx slash has a similar motor and I have ran that way to hot just like you without any drop in power. The only failure to it has been directly my fault.
I believe the Maxx Slash, E Revo 2.0 and UDR use the exact same motor. 2200 kv 4276 can. It is longer than the TC Kuron 825, I tried using the Traxxas motor in my ET48 and it wouldn't fit, too long. So I installed a TC Kuron 825 into the Tekno ET48. Runs strong, but I "feel" like the Ten Shock pulled a bit harder. IDK, splitting hairs TBH, but definitely can notice the difference between the Ten Shock 2200kv and the TC 2050kv in the top end. Not surprisingly.
Whoops, my bad, the Maxx Slash uses a 2000kv motor, so on 6s it's definitely not going over 50K RPM, none of the motors you mentioned are.
 
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The bearings I can find are only rated for 36k rpm.
Try Avid RC, TRB RC, Acer, Jim's bearings, Fast Eddy, Surpass RC, Hobbywing, Castle.. trick is to search by dimensions in mm. You should try to look up what size bearings your motor uses, though you can be misled this way. Has happened to me before. The best bet is to measure what you actually have first.
 
If we do the math, a 2200kv 6s motor spins 48840RPM theoretically on 6s. At 3.7v per cell x 6s=22.2v, x 2200kv =48840. 2200kv really is the upper limit I would consider for one of my 6s bashers. There are motors rated higher, Castle often rates their motors to 60k.
I was using my battery voltage on a full charge, or 25.2 volts for worst case scenario.
 
I was using my battery voltage on a full charge, or 25.2 volts for worst case scenario.
I understand, though that's not how the manufacturers rate these things. They go by nominal or average voltage, which is 3.7v per cell. A lipo battery cell has a safe operating range of 3.2 to 4.2v per cell with 3.7 being the middle of the range.
 
There's always some voltage sag when you give it the Beanz. 50,000 rpm bearings should be fine.

I've always preferred rubber sealed bearings for clutch bell use.

Slightly higher resistance, but they retain their lubricant better and are less likely to get gritty/fail.

NYK are the bearings of choice. 👍

Edit: NSK are the bearings of choice. NYK recondition main bearings in large Diesel engines and is not what I meant.
 
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I’m familiar with NSK and NTN, haven’t heard of NYK.
 
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