If your “e-bike” goes 45 mph, sounds like a spaceship, and can beat traffic off the line… congratulations — that’s probably not a bicycle anymore. 
In Washington State, electric motorcycles/scooters over 750 watts are considered motor vehicles and require:
A valid driver license
A motorcycle endorsement
Registration and other legal requirements
Also important: children cannot obtain a motorcycle endorsement. If your 12-year-old is riding a 5,000-watt electric motorcycle around town, that’s not “just a bike ride.”
Parents/guardians can be held responsible for allowing an unlicensed juvenile to operate a motor vehicle and may face citations — or in some cases, criminal charges.
We know these bikes are fun, fast, and popular, but we’d much rather see kids riding safely than meeting us during a traffic stop.
Please:
Know what your child is riding
Check the wattage and classification
Follow licensing laws
Wear helmets and ride responsibly