How fast can a Razor E300 go?
According to Razor officail website description, it is 15mph, that is 24km/h. From its super-sized deck and frame to the 250-watt, high-torque, single-speed, chain-driven motor, the Razor E300 is designed to excite. Whether you’re meeting friends, or just cruising around, teen and adult riders will find big time thrills at speeds up to 15 mph (24 km/h).

Can you make Razor E300 go faster?
Yes. A simple way is to give higher voltage to the motor. For example, add one or two batteries to the scooter to get higher volt supply. The Razor e300 is with 24v battery. You may have a search of Razor E300 overvolt kit , which is using a high voltage 36v controller instead. It is a easy way to upgrade Razor E300 speed.

The controller in the E300 was rated at 250 watts,24 volts.If you check the stock controller it actually puts out 22.3 volts to the motor (remember the motor will run off 12 volts but just not at full power and will run up to 36+volts-overvolted).
Hub motor E300 Razor upgrade Kit
We got an inquiry recently as this “I have two stock E300 Razors that I would like to upgrade. Do you have a complete kit available? If you do please send me the part number so that I can order.”
As we know that the original razor E300 is a DC motor with chain to drive the scooter. Most DIY or upgrade kit are to change the dc motor to big power or to add motor batteries to the scooter. If you like to do a different upgrade, you could have a try our E300 Razor upgrade hub motor kit.

This Motor tyre size 10×4.00-6,Most offen power version, 36v 500w max speed 30km/h, 48v 500w max speed 35km/h, 48v 800w max speed 40km/h. And if you like, it can use 9×3.5-6 tire too. For a motor, higher voltage will get higher speed. Our controller works with 24v,36v, and 48v battery. That means you can use the different voltage upgrade as you like.
If you like to get a super fast or more powerful, Lonnyo motor aslo have a recommended scooter hub motors as follows,
The above two motors are very powerful and fast scooter hub motors, you need to consider the battery size to your scooter. Any way, if you need a lower power and speed to fit well your battery, and like our motor appearance, it is also ok to customize a lower power version for each specific request.