[MichaelBick]

Originally Posted by Owen Busler

The graph shows that over just 20-30 seconds a stalled 775 will burn out and provide no torque. Taking that into consideration, I would recommend a bag motor (http://www.vexrobotics.com/217-3351.html) Although it has a lot less power, it is okay with being stalled for a little longer (http://motors.vex.com/bag-motor)

There is a bit more that goes into this decision. If you look at the graphs 775Pros don't really mind stalling @4V. If your mechanism design/gear ratios don't need more than .237N*m (AKA .71N*m * 4V/12V) of torque while stalled, you should be good.