The 2017 Electrified S & X has a maximum pedal assist range of 120km, when set to power level 1, and ridden in optimal conditions. An average of 60 km range can be expected if you ride on the highest USA-only speed setting of 32 km/h. 

The actual range will vary based on particular use conditions like power assistance level, tire pressure, rider weight, battery age and condition, riding style, environmental and climate conditions. 

Of course, if the battery runs out, you can still ride it like a normal bike.