This model contains two inertias which are connected by an ideal gear where the friction between the teeth of the gear is modeled in a physical meaningful way (friction may lead to stuck mode which locks the motion of the gear). The friction is defined by an efficiency factor (= 0.5) for forward and backward driving condition leading to a torque dependent friction loss. Simulate for about 0.5 seconds. The friction in the gear will take all modes (forward and backward rolling, as well as stuck).
You may plot:
Inertia1.w,
Inertia2.w : angular velocities of inertias
powerLoss  : power lost in the gear
gear.mode  :  1 = forward rolling
              0 = stuck (w=0)
             -1 = backward rolling