Transmission
A transmission is a sealed power transferring system that can shift gear size to create high power at low speeds or low power at higher speeds. This allows a go cart to be powerful when it needs to be but on a level stretch it can get up to much higher speeds. The transmission is the only way to get four wheel drives on your go cart. This is obviously the best and most expensive choice for off road go carts mainly because it is sealed and you won’t have any trouble with sand, dirt, and rock dust fouling up the drive.

Transfer Case
A transfer case is an addition to the transmission which makes it four wheel drive. The transfer case bolts onto the side of the transmission and uses its power to transfer energy to the front wheels. The transfer case has a flat side that is open that has a gear inside. This gear fits into the transmission panel onto the final transmission gear so when the transmission turns it turns the gears in the transfer case and that in turn rotates the driveshaft on the front of the transfer case which is connected to the front drive axle. All this ensures that all four tires are moving at the same speed.

Torque Converter
A torque converter is the next best thing to a transmission. It doesn’t change gears in that sense, what is does is uses centrifugal force to expand one pulley while compressing the other one effectively changing the gear ratio automatically. These are great for off road applications that will be dry because too much water can cause them to slip.

Centrifugal Clutch
A centrifugal clutch has only one speed and is pliable for a few options. The speed is based on the gear ratio and the RPM factor of the motor. The bigger the wheel on the axle or tire gives it more power and less speed and the smaller the less power and more speed. So, if you use a Centrifugal clutch it is for a specific application.
          Chain driven
          Chain driven clutches are basically the opposite of belt driven clutches. They perform better for wet conditions like mud hopping and marsh 
          lands it is better not to use them in dry conditions such as the desert because dry rock dust and sand will dry up your oiled chain very
          quickly and then seize it up causing it to break links. “Tip” Always brings spare links, a length of chain and tools required to change them if
          you have a chain driven clutch.
          Belt driven
          A belt driven clutch is basically opposite from a chain driven clutch and is mainly used for dry areas such as deserts and dry dirt, and is advised  
          not to be used under rainy conditions such as mud hopping and marsh land.