I've noticed in several posts about people who daul/triple/quad battery mod their cars that at a certain point the motor actually decreases in speed. At times the motor will also make a strange, high pitched humming sound (like an old kettle boiling).
Attached below is a graph detailing the torque / RPM speed of a generic DC motor and how this changes as the amount of current (and power which is a function of voltage and current P = VI) to the motor is increased.
This should hopefully help (and probably confuse!) people into understanding the properties of the motor in their Bit.
I thought that the shaft just heated up the plastic busing and then started rolling around in the hole... like if you take a pen and spin it in a circle made with your fingers... the noise is the shaft doing this (at least i think...)
Linear Mode
