The ME1716 is the smallest sealed brushless motor we have. Still good for 80 amps continuous. ~4500 rpm at 48v, 20 pounds.
The slightly longer ME1718 is good for 100 amps continuous with a Peak rating of 300 amps for 2 minutes. ~3500 rpm at 48v. Approx 26 pounds.
These are used in our 16kw motorcycle kits and 5kw kits, both of which use Curtis 1232 type controllers.