The CGO 600 eBike is designed to withstand a maximum weight of 120 kg (265 lbs).
We haven't lock the maximum speed CGO 600 can reach actually, which meas you can ride as fast as you can by your effort. However, according to local regulations, the maximum assist speed is limited to 32 km/h (20 mph) in the US, or 25 km/h (15.5 mph) in EU, which means that if you reach that speed the motor will stop assistance to help you get a higher speed but of course you can be faster only by your effort.
In addition, we can not tune the maximum assist speed for any purpose, including change a bike with 25 km/h speed limit to 32 km/h.
We strongly recommend you to ride on a speed below the local regulation required for your own safety.