I bike commute to work 2-3 times per week. I've been thinking about getting a e-bike, alternating rides, and going 5 days a week. I know absolutley nothing about ebikes. Hopefully you all can answer a few basic questions I have.

1. If a e-bike says 18mph top speed. Is that all it will literally go? If I also pedal can it go faster? Or does pedalling only help extend the range? Will it go faster down hill? On my pedal commute I frequently get over 25mph, will a e-bike potentially go slower then I am used too?

2. I am assuming the speed and range are also effected by a riders weight? If the speed/range is tested for a 175 lb man, will it substantially change for someone over 200lbs?

I'm sure I'll have more questions coming along..