Board Thread:General Nerf discussion/@comment-35070608-20190503130823/@comment-27306930-20190506035526

Sorry Z. Some of these new 130/180 DC motors are what they call "open-ventilated". They incorporate slits in the motor housing, aka vents. The armature (the part that spins inside) acts like a little fan and circulates air inside the housing to cool the motor. Between electrical arcing in the commutator and induction in the windings, some of these little Nerf sized motors generate a LOT of heat.

Stock motors, and even many high performance motors like Honey Badgers and Rhinos don't have vents. They radiate heat through the motor housing. But many of these new neodymium motors like FRVs incorporate vents to help dissipate excess heat.

I realize some of you haven't handled neodymium motors yet. When you put regular 130 motors next to each other, nothing much happens. But when you put a pair of neodymium motors next to each other they snap together. The magnetic field is amazingly strong, even when they're off.

So like the larger commercial versions, these small neodymium motors often incorporate motor vents to deal with heat.