Drill Motor Problemos

Errrmm… Ok… this could be less than good,
We put some white tape on the flexible coupling, mounted an optical sensor above it, and breadboarded a resistor onto the output diddly-boob. Anyhow, with the help of an oscilliscope, we found that rpm were about 320… not a good figure. Also, there was a 15% difference between forward and revers, but that was sorta expected. What kind of rpm are you guys getting on the gearboxes, no-load?

Did you check the battery’s voltage to make sure it’s 12V, or better yet, check the voltage at the motor’s terminals? What is connected between the motor and the battery? Is there anything connected to the output shaft?

It is the listed speed, I tested it with a strobemeter (verry accurate), also the opt sensors responce time is >1ms