First I am not the author of this, that would be mrasmm!

Link to original post [link]http://www.rcuniverse.com/forum/m_5628228/tm.htm[/link]

It is very simple, run them at low speeds/voltages for about 2 hours in each direction. It really does not need to get more complicated than that. At a slow speed the brush has a chance to conform to the armature. In effect it takes on the same shape as the armature. At high speeds on initial use the brushes can become pitted and wear prematurely.

Yep like panther said... You can take it one step further but i don't think it's needed to much for tanks but it does give motors more power and RPM ... You run the motor under water...Yes under water on low voltage 2 to 3V for a few min and it will break in perfectly ...under water makes the brushes seat much faster to the com and its cooler and no arking to foul the com during break in.... the minerals in the water help to seat the brushes fast so only put it in for a few min no longer than Five i would say.

Then shake it out let it dry in a warm place and re oil the bushings and your set. NEVER HEAT THE MOTOR AS HEAT WEAKENS MAGNETS!!

I did this for slot car racing and it worked great also on sme brushed RC motors as well.

I was trying to share info as a friend of the author and a electronics tech I know how to break in motors. The water method is in there also and I agree it is the best method as Ive used it alot, when electric helis 1st came around.