Hey credence,

The heat-sink indeed runs hotter than the motor itself. I also used some heat-conducting paste when clamping it on, so it's really as efficient as possible. After 3-4 minutes of flight, the underside of the motor is too hot to touch for even a second. The motor also starts to emit an alarming aroma of overheating windings and plastic. No smoke, but that's probably just because I usually give it about 5 minutes to cool off for every 2 minutes of flight.

The ESC runs moderately hot, but I can still keep my finger on it's heat-sink. The batteries run little more than warm to the touch for most of the flight, but quicly pick up temperature at the end of their discharge-cycle and are usually 40-50 degrees C at the end of the flight, when the LVC kicks in at 3V per cell. I haven't measured exact temperatures yet.

BTW: The Align BL-420LF I'm intrested in as a replacement has a built-in cooling-fan. The heat-sink from my current motor should also fit it, for even more extra cooling.


Grtz,

Traveller