We can make a kit for the Razor E100 scooter which has a variable speed controller and throttle. We would just need to know what version the scooter is so we can wire the kit to work with that version.
The version is coded into the scooter's ID tag and is the two numbers in the red circle of the ID tag shown below.
A controller rated for a 300 Watt motor, such as our 350 Watt controllers, could be used with the E100 scooter's original motor. The E100's motor is rated at 100 Watts so a 350 Watt controller would output more current than the motor is rated for which under the right conditions could cause the motor to overheat, so that is something to consider when choosing the parts which will be used for the modification. If the motor overheats its coil insulation could burn off and cause a short circuit which would burn out the controller.
So it is kind of a gamble to install a 350 Watt controller with a 100 Watt motor with plans to upgrade to a 300 Watt motor in the future. If you want to play it safe then using a 150 Watt controller with the 100 Watt motor would be the best bet, however, if you want to take a chance then the 350 Watt controller could be installed.
Please let us know if you have any questions. If you would like a kit then please let us know the scooter's version number and we will be glad to make one.
Thanks for your reply. Sorry for how long this has taken, we have not forgotten about this kit it has just taken us a while to figure it out and make it.
We have the kit ready to purchase now. it is our item # KIT-E100. Here is the link to it: https://cart.electricscooterparts.com/ProductDetails.asp?ProductCode=KIT-E100
On the Razor E100 scooter, the original throttle and brake lever are not compatible with the variable speed controller in the kit so we had to include a new throttle and brake lever to make all of the parts compatible with each other. The kit contains everything needed to convert the E100 scooter to have variable speed control and to remove the push-to-start feature so the scooter starts running as soon as the throttle is twisted.
Please let us know if you have any questions.