What's wrong with my motor?

Hi everyone, I'm somewhat new to this hobby so go easy on me. I've had my 2wd brushed Torment for a while now and it's been running fine until recently. Not too long ago I ran it and the motor began to smoke a tiny bit. Not only that, but the motor was really hot. Concerned, I stopped using it and saved it for another day. Today I ran it again, where I noticed a large drop in performance after only about a couple minutes of driving. Looking at the car, the motor was all smelly and was smoking a whole lot more than the last time I used it. I'm not to sure what is going on here, but I believe that my motor may be 'fried'. What is going on here? Should I consider getting a new motor, or try fixing the problem itself?

Note: My car is completely stock, except for the fact I have upgraded tires in the back and also that I use a 2s 5000mah Lipo battery

If the motor is smoking an loss of performance most definitely it is fried or frying and may damage the esc if driven around like that for a while but the esc might have some sort of protection but who knows. When the rear tires are bigger than stock that may be the reason. Having bigger tires or running on rough or grassy terrain will put more stress on the motor and will cause it to wear out faster or just burn up right away.

I would recommend getting a 550 size brushed motor if you want something cheap but good brushed motors are hard to find. A lot of people give traxxas **** about how their Titan motors are bad but for being in a ready to run model those motors are pretty good in my opinion because they aren’t built for a lot of stress (like big power systems and over gearing) but if you gear a traxxas 12t 550 the way it wants it’ll sit and do donuts all day.

A more expensive (at first) option would be brushless. Good systems can take a lot of abuse but going brushless may cause you to break more drivetrain parts if you aren’t careful with the throttle and in that case if it ain’t broke don’t fix it or you’ll spend more than you need too, ive made that mistake

Thank you for the response, I'll be looking into getting a new motor. I want to stay cheap, so I'll be looking for a brushed one. If I get a different brushed motor that is more powerful than the original stock one, will I have to change anything in the car, such as the ESC? Also, is there anything I can do to reduce the chance of something like this to ever happen again? I don't really want to buy a new motor every year or so.

Get a can of "motor spray" and insert the straw into one of the vents near the endbell of the motor, tilt the car a little so the spray will run out of the end of the motor. I do this over a bucket with a new white paper towel to catch the rinsate. It also helps me see the color of the liquid running out. I spray until it runs clear, not gray. This helps keep the brushes and commutator clean and will help prolong its life. Clean the motor this way after every dirty or dusty run (or wet!), or after every few runs if in a clean environment (like indoors on a race track). After spraying out the motor, apply a drop or two of oil to the bushing where the motor shaft protrudes from the endbell (the motor spray will have flushed out any lube).

In my AMP i switched from the stock 20T 540 size motor to a 15T 550 size motor and didn't need to change a thing. Keep in mind that your run times will be reduced as the larger/faster/more powerful motor will want more electricity!

WaterLoupe said:

Thank you for the response, I'll be looking into getting a new motor. I want to stay cheap, so I'll be looking for a brushed one. If I get a different brushed motor that is more powerful than the original stock one, will I have to change anything in the car, such as the ESC? Also, is there anything I can do to reduce the chance of something like this to ever happen again? I don't really want to buy a new motor every year or so.

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Heat kills motors so do not let the motor get to hot. Get a IR temp gun I use this one https://www.harborfreight.com/non-contact-pocket-thermometer-93983.html and try to keep the motor temp below 160F never more than 180F. You do this watching you run time and checking temps throughout your run. You gear your motor (pinion) to where when you run you do not overheat your motor no matter what motor you run. This will vary from person to person because unless it is completely stock no one runs their rig the same. My advice if you like your current motor gear it down (go with a smaller pinion) to help with heat extended run times will create more heat. Once you find a motor you are happy with and gear it right watch temps for a couple of runs then you should be good to go. Every once and while it would be good idea to clean the motor then put a drop of something like 3 in 1 oil in both ends of the motor where the shaft rotates in the bushings.

Sealed can brushed motors are a consumable (disposable) item the brushes wear out, the bushings wear out or they burn up then you throw them away and get another one. If you take care of a brushed motor it can last a little while but ultimately as said above they wear out and you will have to replace them. I don't stay brushed for long on anything I own brushless is just so much more fun. A cheap less than $40 dollar esc/motor is still better than running most brushed motors.

Kylerc is right about getting a 550 sized brushed motor is what you want if you stay brushed. There are only two 540 motors that I would run in a 2wd and those are the HPI 15t Firebolt or the Reedy Radon 17t motors but as said before still need geared appropriately. A 550 brushed would be a better choice though in a SCT or MT a bit more low end torque with a 550 brushed.

WaterLoupe said:

Thank you for the response, I'll be looking into getting a new motor. I want to stay cheap, so I'll be looking for a brushed one. If I get a different brushed motor that is more powerful than the original stock one, will I have to change anything in the car, such as the ESC? Also, is there anything I can do to reduce the chance of something like this to ever happen again? I don't really want to buy a new motor every year or so.

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Brushed motor lifetimes are so variable it’s hard to predict but I’ve heard of motors lasting up to 1-3 years which is a big window of time but like I said there’s so many variables such as; gearing, run temps, conditions run in, maintainance, and plenty others. Also if you have the stock brushed esc I’m sure it’s rated a 12t 540 minimum and let’s say the Titan 12t 550 I’ve heard is almost similar in the length of copper or something as a 15t 540 motor has but I’m not completely sure. But anyway what I’m saying is a 12t 550 won’t do the esc any harm unless over geared.

All of these responses have been really helpful to a newbie like me! I have an idea on what brushed motor I'd like to get, but can I get some some other suggestions? I'm interested in this one, as suggested by you guys. Also, how hard would it be in install a new motor on my Torment? It's my first time ever doing this.

I’m sure that motor will fit but I don’t know if it would overheat or anything because I have an associated b4.2 with that motor in it and it runs great but it’s a light vehicle.

That motor will run a car the size of the slash (traxxas slash comes out of the box with that motor) but it might get hot because stock gearing in a traxxas slash is 16/90 or mine was anyway but the smallest pinion I have been able to fit into an ecx vehicle without problems or modification was the 18t pinion with 87t spur and even then the gear mesh was bad so it shredded gears all the time.

The torment may be lighter than a traxxas so it might work.

Actually now that I've done a whole lot of research, I might consider going brushless. There aren't that many options for a good brushed motor, and I feel like spending a couple more bucks would be worthwhile. Now that this thread has a completely different topic, I'll start a new one about going brushless.

Sounds good hope you find a good one

Brushed motor.

They go when they go, sounds like it fried. Throw in a new one and drive on.

WaterLoupe, There are some great brushless motors out there. I myself run the Castle combo's on my cars and trucks, they run around $ 110 but you can pick them up on eBay for a lot less. I usually run the 3600kV to 4800kV. They come matched with the Castle ESC. The lower the kV the more torque you will have off the line and a little less top speed. The higher the kV the less torque but more top speed, so it all depends what you want and what you do with your vehicles. I do a lot of street racing and some 4 wheeling. It's great hobby and the parts are cheap accept for the initial buy of the vehicle. The most expensive items are the LiPo batters, brushless motors and tires. Also going to all steel or harden steel and aluminum parts can get a little pricey, but still cheaper then the above mentioned. If you like the hobby it will take you awhile to get up to par on repairing or upgrading your vehicles. As you can see from the images I do a lot of up grading and use a lot of cooling. The fans run on their own LiPo drone battery and are switched. Once you familiar yourself with the hobby you will be able to do the same. There is a lot of info on this forum and a lot of smart people, some smarter then me, so anytime you need information we are all here to help. Happy RC'ing