Drivetrain Motor Problems

We are having an issue with our drive train and we aren’t sure exactly why. We can drive fine for like 10 minutes, but then our motors slowly start shutting down, to the point where we can’t move at all. We’ve ruled out the batteries as being a possibility. Also, when we lift the robot up after the motors stop working, it spins the wheels just fine. The same problem occurred for us last year. We have a feeling it is friction issues, but we really don’t know. Any ideas as to what it could be or suggestions as to how to fix it would be much appreciated!

Sounds like you don’t have enough torque. What gear reduction and wheel size are you using? Can you send pictures?


We are using 3.25 inch wheels with a 2:1 ratio. We are also using the green motor cartridges. On top of that, it is using four total motors, with two attached to one gear train and two attached to the other.

400 rpm is pretty high, even for 3.25” wheels. I recommend dialing that down so you have enough torque to get past your system’s friction
(I’m assuming by 2:1 you’re using the vex notation)


Okay, thank you so much! We’re going to look into coding it to have a lower velocity, and if that doesn’t work we’ll switch the motor cartridges out with red cartridges. In the event that neither of those work, we’ll just adjust the gear train. Again, thank you so much!

This won’t increase your torque. It will only decrease your power. You’ll need to change your gear ratio through either the cartridge or external gearing if you want to increase the torque


Sounds like overheating. To check, touch the motor, if it is pretty hot it has overheated. A easy fix is upside down compressed air in a bottle (air duster). If it is upside down it will force freezing air out and cool your motor so you can use it more

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I think I know why it’s slowly getting slow its because it’s overheating or your battery is dying. To find out if your motors are overheating is to put your hands over the vents and when it’s warm/hot that means it’s overheating. It happened to us a lot of times but it’s because we use it a lot.

The casing is plastic, which is a very poor conductor of heat- so this doesn’t do much. A better alternative is hot swapping the actual motor (or just fixing the root issue which is not having enough torque)

If you’re more curious about motor heating I highly recommend checking Jon’s response in How to Disable Motor Overheat Protection - #16 by Jon_Jack


Disabling overheat protection is really bad for your motors, and will lead to burnouts (happened to me twice). I really do not recommend disabling overheat protection since there is a shortage of all the V5 electronics.

Air duster works fine for me

I recognize that. Reread my post and the post I’m referring to. I’m not saying to disable overheat protection lmao


I can’t read lol

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