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  1. #1
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    How do you make brushed motors not die?

    My cousin just got a brushed rustler (sorry, slashers), and his motor already died. How do you use a brushless motor without it dying?

    He is a beginner in the hobby, and I don't want him to lose interest becouse he needs a motor every week or so.

    Of course you shouldn't pull/push heavy objects with any RC, especialy brushed RC's. What are other things you should(n't) do with a brushed RC?

  2. #2
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    With a new brushed motor, run it in distilled water at about half throttle for 10 minutes. This is called breaking in the motor, and it lets the brushes wear to fit the commutator better to allow for better contact which results in more efficiency, more power delivery, and less wear overall. After the run, spray it work non chlorinated brake cleaner (optional) and then spray dry with compressed air. Then put a drop of thin bushing oil on each bushing the shaft rides on, and youíre good to go.

    Donít pull objects, that kills brushed motors that arenít torquey enough. Also doing instant reverse to forward throttle to make the truck wheelie kills them, so donít do that either. Basically, hard acceleration and heat are what kills a brushed motor. Try to keep temps at the commutator (brass colored copper thing inside the motor where the grey rectangular brushes contact it) under 130įF for safest operation. And if youíre overgeared, the motor will have too much load on it and will die soon from that. If you use the stock gearing you should be fine, but donít use the optional speed gear.

    Traxxas titan 12 turn motors are pretty strong and last a long time when cared for properly, so you could start fresh with a new motor and follow my guidelines and you should have a motor that definitely lasts longer


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  3. #3
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    Tnx, I'll send him this.

    So it's mostly 'Don't make it work to hard, or it won't work at all'? Sounds like me.

    I've also heared somewhere (i don't know where), that brushed motors don't like dust. Is that true?

  4. #4
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    Yeah a brushed motorís life can be drastically reduced if run in very dirty conditions. Sand is basically a no-no. Mud kills them too. After a run in a messy environment, spray non-chlorinated brake cleaner on and in the motor until it drips out clean, let it dry, then put a drop of thin bushing oil on the rear bushing (you donít need to remove the motor from the truck). Dust is to be expected to be honest, so just whenever the motor is visibly pretty dirty, is when youíd need to clean it. Every 15-20 ish battery packs, it would be a good idea to remove the motor and run it in distilled water for like 30 seconds to clear everything out, then dry with compressed and and do a drop of fluid on the bushings again. Maintenance basically


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  5. #5
    RC Qualifier Calebs0615's Avatar
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    When you do the distilled water method, do you drop the entire motor underneath the water? Like half up the wire leads or something?

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  6. #6
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    Thanks for the info, I'm sure my cousin will be happy with it.

  7. #7
    RC Turnbuckle Jr. Greatscott's Avatar
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    Quote Originally Posted by Emaxx Racer View Post
    With a new brushed motor, run it in distilled water at about half throttle for 10 minutes.

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    Do not recommend doing this at all. This is an old racers' trick to break in a motor, cutting the brushes in to the "sweet spot" so that the motor makes maximum power. The water acts as an abrasive, quickly wearing (cutting) the brushes down against the commutator, so the brushes are the same profile, giving maximum contact, and maximum power transfer. This sounds great, but racers back then would go through one motor throughout a night of racing, then throw it away. The problem with doing this break-in method is that you are literally removing about half the motor's life in 10 minutes.

    A better break in method is to just drive the truck on relatively flat and level concrete/blacktop for about 10 minutes at 1/3 - 1/2 speed with a 2S pack, keeping as constant of a speed as possible. It is a bit boring, but it get the brushes profiled with the comm, but not eating half of their life away. After the 10 minutes, blow the motor out with air, put a drop of light machine oil on each bushing, giving the motor a spin to work it in, then put it back in the truck.

    A giant factor in brushed motor life is maintenance. A lot of people do not clean their motors, and they go out fairly quick. And, the conditions that you run in should determine how often you clean the motor. Cleaning the motor is easy:
    • Remove the motor
    • Blow it out with compressed air (30-50psi)
    • Blow electric motor cleaner through it until it runs clear
    • Blow the excess cleaner out with air
    • Let the motor dry (overnight is best)
    • Lubricate the bushings
    • Resinstall
    • Drive it like you rented it...

    How often...
    • Slightly dusty conditions: Clean every 15 - 20 packs or so.
    • Dusty conditions: every 10 packs or so
    • Running in water, mud, and/or sand: Clean when you get done running that day.

    This is one big reason to go brushless, also, brushless motors are a lot more efficient, so more of the power is converted into speed.
    Submarine Qualified, Chief Inducted, Navy Retired

  8. #8
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    He’s probably getting brushless in feb. I’m selling him my motor in feb.

  9. #9
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    Yes you can dunk the whole motor and itís wires in the distilled water. Distilled water is one of the best insulators. I get a gallon of water from food lion for under a dollar, cut the top off, drop the motor in with it hose-clamped to a stick so I can hold it and so the wires donít twist up when thereís throttle applied, and give it half throttle on 2s lipo or 6-7cell nimh/nicd.

    I said 10 minutes in the water because thatís about how long it takes to seat the brushes in sealed endbell motors since they are made to last longer rather than make more power, so the brushes are harder, so it takes more time for the brushes to wear. The goal is to make the initially-flat profile of the brushes round to match the commutator.

    Iíve done this with almost every brushed motor Iíve gotten since I realized this trick. I do race my trucks, but I do this trick to any brushed motor. Crawlers and bashers and racers alike. Iíve got two brushes 27t motors in one of my clodbusters that I broke in this way (more meticulously though) and itís lasted me 3+ years and still going strong.

    Doing the water method is a better breakin method than just driving it lightly around because the water softens the brushes to make the wearing process happen quicker than running it dry, and also the water removes the worn brush particles away from the commutator as to avoid scratching it as much.

    There is a lot of debate (always has been) about whatís the best way to break a brushed motor in. I am a firm believer of the distilled water method. There are other methods out there where guys go to extreme measures with their breakin process like before brushless systems were around, and guys would easily kill one motor per race (~5 minutes) but the motors ran wicker good. It all comes down to what you feel is the best. Iíve been in the game for about 10 years and have friends who have been doing it much longer than me who I learned some brushed motor info from, as well as countless hours researching stuff online. My stuff runs great and lasts a long time, so you can take my advice or leave it. But regardless, break in the motor some way mentioned in this forum, since it will be much better than no break in at all.

    Note that if your motor, esc, batteries, or wires begin to get hot during the breakin process, immediately stop and do the dry method. This can happen with brushed motors with internal fans since thatís a lot more resistance the motor has to overcome (the fan pushing the fluid continuously).

    And if your water turns black pretty quickly, dump it and get some more water so that your using clean water. The blackness would be worn carbon/brush particles, which are electrically conductive.

    Somewhat related, I tried to break in a new Titan 775 I got from a friend for my Summit. I ran it in distilled water at about 4 volts for nearly an hour and the brushes still didnít wear enough, whereas my friendís Holmes Hobbies torquenaster proís brushes wore in in about 6 minutes In distilled water. . That goes to show that many sealed can motors have harder brushes than quality open endbell motors, so you need to run them longer compared to open endbell motors.

  10. #10
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    I just want to further add that the water break in method is NOT recommended by Traxxas. For best motor life, Traxxas recommends following the break in method outlined in your vehicle's manual.

    Can you get more power and speed out of the water break in method? Yeah. I remember seeing motor dyno results back in the day (20+ years ago) proving that fact. Will the average R/C driver notice, especially a newbie? Probably not. Most people, especially those new to the hobby (or those simply looking for the best motor life) should avoid the water break in method.
    "Happiness depends upon ourselves." -Aristotle

  11. #11
    RC Champion zedorda's Avatar
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    I sat and thought about by own wall of text I could produce about the several scientific papers published by both Honda and Toyota after their research in the late 90s connected to their interest in electric vehicles. One particular paper about water and its effect on carbon based brushes was very enlightening.

    Trying to offer the whys for things tends to just generate arguments here. So I am just going to offer how I changed the way I break-in my brushed motors now that I learned from those studies. Because I use to do the same thing Emaxx Racer does. Not that it is a horrible method but I now understand why there is a better way and make use of that information.

    I now break-in my brushed motors by mounting it in my drill press. No power going through the brushed motor only the drill and run it for 10 mins at 2000 RPMs. No water or oil added. I actually use QD Contact Cleaner before and after. Then apply the oil and work it in.

    Should you do it this way? Up to you really. Because in the end we are just splitting hairs. The real quantifiable differences between each method is minor. The point is just have a method to break-in the motor and don't just go hog wild on the first run and botch the whole thing up.

    Good luck and enjoy your rig the way you want too.

  12. #12
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    Using a drill is a good way to do it, I've done that myself in the past. I've also had decent luck simply removing the pinion gear and running the motor at a low speed.
    "Happiness depends upon ourselves." -Aristotle

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