Do you? I can't dig up anything particularly good, but what I do find indicates in the mid-90% for practical electric motor efficiencies.

This says 85-95% efficiency for the motor in an EV: https://matter2energy.wordpress.com/2013/02/22/wells-to-whee...

This says 93% for a brushless DC motor: http://electronics.stackexchange.com/questions/58236/why-doe...

I found a bunch more of similar quality searching for "ev motor efficiency" and similar.

I'm not particularly satisfied with those, so if you have something better, I'd love to see it!

And don't forget, you have generator efficiency to deal with as well. If you're 90% on both sides, the system is only 81% efficient. Ouch!