The original 24 Volt 250 Watt Razor Ground Force motor can be ran at 36 Volts and its power will increase to around 500 Watts at 36 Volts.
However the original 250 Watt motor is designed to be ran at 24 Volts and it will run hotter at 36 Volts than it doe sat 24 Volts and it could burn out if it gets too hot. The motor will most likely survive if the go kart is driven only on perfectly flat ground because flat ground does not put much of a load on a motor, however if the kart will be used to go up inclines at full speed that could overheat the motor.
You could certainly install a 36 Volt controller and upgrade the battery pack to 36 Volts and then see how the original motor handles it. Or the original 24 Volt 250 Watt motor could be replaced with a 500 Watt motor at the same time as the controller and battery pack.
Overvolting a 24 Volt motor to 36 Volts will make the motor spin a lot faster and is the best way to go if you want to increase the top speed of the kart. Running a 36 Volt motor at 36 Volts will most likely make the kart have around the same top speed as it originally did however will make it have faster acceleration and be better at climbing hills.
As far as a 36 Volt 500 watt controller goes if the Razor Ground Force is a version 1 through 12 then we have a plug-and-play controller that will directly replace it which is item # SPD-CT312C1:
If it is a version 13 or higher then the SPD-CT312C1 would not be a good choice upgrade the kart to 36 Volts. If you have a version 13 or higher then please let me know and I will research and recommend the best controller for it. I am not sure if you want the kart to go faster or go the same speed and have more torque. If you could let me know what your modification goal is then I would be able to recommend a motor for it.
We also have a wide selection Razor ground Force and Razor Ground Force Drifter upgrade modification kits available on this page:
Hi there. I love my Razor Ground force, but I think that It should go a little faster. So, i'm only a little new to this, but I know my way around pretty good. So I want to put in a 36v 500w controller for it, and add another battery. But here is the catch: will I have to upgrade the motor? Also, It would be awesome if someone could provide a good controller, wiring diagram, or a motor. Thanks!