[suicideneil]

Watts = volts x amps.

920watts would most likely be maximum continuous output.
87A the max continuous rating.
105A the max peak rating for 30 seconds or so.
30V the max rated input voltage.
1.70A is probably the idle current.

In theory, the max current draw you will see is around that 87A area, but peaks will be higher, up around 120-130A usually, depending on vehicle weight, gearing, kv rating of the motor etc etc.

920W / 14.8V = 62A continuous, but as a general rule anything that can provide 80amps or more is fine; the higher the capacity & C rating, the better ideally.