Answered: Motor slowing down drastically? Why...


I am having a major problem with one of my motors that was being used on my Vex Elevation robot…

The problem:

-motor starts fast and gradually over a 20+ second time period slows down drastically
-motor heats up during this process stated above
-interior motor gears were replaced and nothing changed.
-Currently the green and black (front and back cover) of the motor and the gears have been removed. This rules out the possibility that the motor is being stopped by an outside external force
-the motor was not put under any heavey stress loads. The gearing that it was put under dealt with high torque which it should have been easily able to withstand
-these symptoms occur no matter what motor port is used
-batteries have been switched and have been ruled out as a cause of this problem
-extra: code running at the moment is the default code
-after a bit of cooldown the motor is able to run at full speed again but immediately starts slowing down

Does this mean that my motor has lived its glorious life and needs to be replaced? Is there a possibility of you guys taking a look at it (shipped to you) and repairing it without having to pay the full price for a new motor?

If you have any ideas that would be great. The VRC competition is only a few days away and this definitely is a problem that I hope you guys can help me resolve as soon as possible.



**Yes, the glorious life has come to an end. Our minimum repair is over twice the cost of a Motor, so just replace it.

There is a current limit internal to the Motor to help protect it. High torque loads put maximum current draw on the Motor causing excessive heat and cause the current limit to trip. As the Motor cools down the current limit is reset and thus allows the Motor to work again. My guess is some of the internal winding of the Motor have melted together over time.**

Thats sounds correct. Thank you for the quick reply and I will be sure to order a new motor as soon as possible.