Hi, Just a thought, if all the gears are the same size, and all rotations are the same speed, you could set it up with set driven keys instead of dynamics. Have the first gear as the driver, then all the other gears as driven. Just set it up so that if the first rotates clockwise (+value) then the next rotates counterclockwise (-value) and so on. Then all you have to do is key the first gear and the rest should follow.

Back to dynamics, you could try setting Passive Keys. Under the Soft/Rigid Bodies Menu you can set Passive keyframes for passive rigid bodies.

Hope this helps