Motors of unknown specifications
 

Find a tranformer for an electric train and hook the motor(s) to it. Check the polarity of the wires to the motor if possible. Start at low voltage and increase it until you see smoke. That's when you stop, throw that motor away and try another one. Actually, as suggested try a train transfomer or a dC power source that has an ajustable voltage that will go as low as 1 or 2 volts and top out at around 9 or 10 volts DC. Unless you have a tach you won't know the RPM's but you should be able to tell when you are over rev'd. The motor should not run hot (warm may be ok), if it does you are pushing too many volts.

Motors of unknown specifications
 

BOOboo, I loved your answer! I nearly fell out of the cockpit laughing![img]i/expressions/face-icon-small-smile.gif[/img]
We needed that up North here where winter was so hard on our budgets.
You at least followed up with good information without Zedoh buying a lot of testing equipment[img]i/expressions/face-icon-small-happy.gif[/img]
Thanks for a good laugh
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