My ears were ringing
I've been working on sensored outrunners for years now. It wasn't just as easy as slapping sensors on or in a motor, and positioning is very precise as compared to 2 slot motors. Delta Vs Wye is also a big concern, it is much easier to work with Wye terminated motors as they have a zero timing point that is mechanically accurate. Delta terminated motors essentially auto advance about 20 electrical degrees even with zero mechanical timing. Makes things too touchy for smaller motors.
Here are the first vids of prototyping, 12 slot 8 pole motor. Somehow the sound got stripped off. It is actually pretty quiet as compared to a brushed motor or sensorless startup. I didn't feel like I was bothering anyone at the park.
http://www.youtube.com/watch?v=JevFhBvJ0C0
540 framed motors are first to get rolled out. Next I am doing 28mm outrunners if we can cram sensors in. Might have to go external. I am also working on a 54mm sensored outrunner for Ebikes and robotics uses.
Sensored motors and a motor dyno take up most of my time lately. Hopefully one day I will actually have something to show for it!