Whats a cobalt motor and why would I want one?
Rare-earth magnets, of which the most common type is samarium cobalt, are stronger for a given weight and volume than ferrite magnets. Perhaps an even more important reason for getting a cobalt motor is that they also have better brushes, bigger shafts, better bearings, are built more carefully, and so on. For the serious electric flier, they are worth the extra expense.
