[glassdoctor]

I've never done this and it's not my idea... but I think you can use a slave motor to spin the rotor (XLT) and measure the voltage across a coil, to somehow figure the kv.

Also, I read you can measure the rpm while it's running using a scope. (or use an actual tachometer) With the voltage into the motor and the rpm measurement, you can calc the kv.

If you can figure the kv.. that would tell you what it is.