After posting this question I thought of the same thing. I put a meter on the motor like you suggested and gave it some throttle and got a big fat 0.00V. I started testing more things and concluded something strange. I have deans plugs on the motor connection and was checking continuity on each section of wire and found out that I wasn't getting anything pas the deans plug. The wierd thing is is that everthing is intact and soldered. I can't figure out what the problem was. Anyways I resoldered new leads onto the plug and to the motor and it fired right up.
This is my first time with a "stock" motor setup. I made sure there's no binding and the gear mesh is good but the motor seams to get hot pretty fast just holding it in the air and letting the tires spin. Is this normal? I also noticed a lot of arcing on the brushes at first but seemed to mostly go away after a few seconds of holding the throttle at about 1/4. Everything works OK but I just want to make sure