Several years ago Ether released a Simple Motor Calculator (
http://www.chiefdelphi.com/media/papers/2432) that lets you specify a motor and some parameters and it will tell you what the motor is doing at that point (ex specify the current a motor is running at and it will tell you torque, speed, efficiency) The issue is it was only for Windows and a handful of folks don't run Windows... so I took the equations he provided and put them in a simple command line application.
https://github.com/schreiaj/motorcalc-uni Here is the code, or for those of you who just want to try it here's the releases page
https://github.com/schreiaj/motorcalc-uni/releases please try it out and let me know if I can make it more useful to you.
Currently supports CIM, 2xCIM, 3xCIM , Bag, AM775, 775pro, and AM9015 and specifying amps or torque. I'm aiming to add in rpm soon.
Hope you find it useful.