In our little R/C world...reversing DC motor leads won't hurt anything. Most DC motors can be reversed. There are some that can't, but the motors we use in these tanks are typically industry standard RS type motors sizes (380, 390, 400, 480, 540, and 550) that are neutrally timed (as opposed to forward or reversely timed). The 540 and 550 motors are not common though due to their size, but there are transmissions that use them. Neutral timing means the motor runs at the same RPM regardless of whether or not it's being run forward or backward. A motor with a forward timing would run faster forward than reverse. A reverse timed motor would run faster in reverse than forward.