I bought one BS motor. So far, I cannot find any way to get as much power out of it as I can out of a MS motor. I am testing with a Robi dyno at 7.5 volts. The BS motor is 5-10 watts weaker at every AMP step from 20-45. It has more RPM, but lacks power. I've tried every trick I know, and these tricks always work on a MS motor. Is there something different I need to try for the BS, or is the BS motor I bought just a dud?