heat sinks work wonders. i dont know about wd40, but i do know that aero car makes a brush lubricant that is really super conductive. this means less electrical brush noise, less heat, less wear, and better efficiency. http://www2.towerhobbies.com/cgi-bin...?&I=LXBVR8&P=7. i dont know about wd40. take a motor apart, measure the impedance of the brushes with wd40, and measure it without. see what happens.