Did I kill my motor?
 

I have a cyclone motor that I usually run with a couple of 28V batteries in parallel. The person who had it before me ran it at 56V, so I tried moving some of the batteries into a series configuration so that I could produce more power. I took this on a steep hill and the motor went off partway up the hill.

I put the system back into the 28V configuration, gave it an hour to cool down and tried it again. The motor gave a little jerk and then stopped.

Did I kill my motor? Or is it something else?

Sounds like it's nice and crispy now.

You probably killed it! If you double the voltage the motor will suck twice the amps. This means FOUR times the power/heat. Most motors will not tolerate this for long.

To be sure, bypass the controller (i.e. connect the motor directly to the battery). If the motor now spins, the controller is probably fried. If still dead it's the motor. Of course you have already checked for blown fuses, right?

To look on the bright side, this could be a great opportunity to rebuild an electric motor from its component parts.

Assuming the motor is broken, which isn't a sure thing if you haven't eliminated controller/fuse possibilities.

If worse comes to worse you can always drill some holes in it and use it as a coaster for your coffee table :)

Well, on power-assist people have been discussing external controllers on these things, apparently the built-in one can pop...