[EricH]

Originally Posted by lukevanoort

The ones I'm thinking about don't need air supplied to them. They are fully enclosed, using air instead of balls, oil, etc. They are very low friction, but need insane rpms to work.

Define insane RPM. I think the CIM is the motor with the fastest free speed. It's about 5500 RPM (I think). Unless your definition of insane is insanely low, or you gear a CIM (or any other motor) up, you won't be going anywhere near fast enough to be able to use one on a robot.