Best way to cool CIM motors?

[theawesome1730]

For immediate results in a pinch, you can use an can air duster upside down so it blows out liquid. It works well in a pinch, but the best solution to your problem is to equip some kind of braking mechanism like a bike disk brake and caliper attached to a servo or pneumatic cylinder so that you don't have to constantly run the CIMs at stall to hold a stack. A fan may work reasonably well, but trying it out is the best way to see for yourself.