John,

Cell phone connection was very bad, so we couldn't discuss details. He'd
first mentioned it last week and I'd gotten as far as some Google work
and finding the SIC article. He called today as he just found out he has
a couple warranty motors coming back. It's rare for him to get a
warranty return and bugs him a great deal, he wants to get to the root
of the problem. Currently has no means to quantify performance.
They are, his description, air coil, or ironless rotor motors. Fast
response, low inertia, low HP. While he has known good motors (not
rebuilt), I don't know if he also has any specs.
I'll know more when my customer gets back next week. Did tell him I
needed to know what he was trying to measure. Going to complicate things
if he needs to measure say, rate of acceleration, etc...

At the bottom of the learning curve,

Jon