I call BS. BL motors are only limited by the load on them, and the amperage they can get. After a certain point, the bearings blow up or the windings and/or wires heat up to the point of melting solder. You can change the windings, but that's rather pointless.. unless you are very good at it, the motor will have issues, and it's lots of work.. might as well just buy a motor with fewer turns.