toolman2 wrote:it would be good to hear from luke and others about how much real world continuous power these rc motors can take -my guess like any motor it may be able to do 3 times this (say 9kw) for a burst or running at light load and high rpm, but maby closer to 3kw in an ev that has massive start loads, long hills and not much cooling etc? let me know your thoughts people?
Well, in my application, I setup extremely good active cooling on my HXT motors. I went through a lot of effort to enhance the cooling potential of the motors to the max, so I would not expect this level of power handling from motors just bolted up to some steel brackets etc.
I lapped the anodization off the face on a machinist flat block with 600grit paper, then went down to 1000grit. Then mounted them to a lapped flat surface on a 1/2" plate of 6061, and mounted giant CPU heatsink with a thermostatic controlled fan on each heatsink that kicks on if the base of the stator reaches ~170F. The fans have only turned on a few times total that I'm aware of over the whole time I've had the bike. You gotta power up a very long hill with the pair of 18FET Methy controllers at 50-60mph to get the motors hot, and that's dumping 8,000-10,000watts into each motor. In my application, the controller heating is still the weak-link before motor heating.
That's my real-world experience with the big HXT motors.