[JERRY2KONE]

Go-karts this size usually do not use any kind of diff. The rear axles on these applications are usually a solid rear shaft with a sprocket bolted on, and they turn just fine. If you do a little research about karts that have been fabricated to run under electric power most if not all of them have been setup with a higher voltage system due to the weight factor involved. 36v to 48v may be enough to keep it moving witout overheating the electronics as long as you have enough capacity. In fact I do not recall seeing any of them with a Lipo battery due to the overall cost for building such a setup. All of them have been built using lead acid or gell cell type batteries, because you can acquire them fairly cheap or they used batteries that were laying around their shop. Using Lipo's can be done, but not cheaply. You would need a lot more than just a few R/C batteries to even make this worth while. Look at some of the E-bike projects that have been done and shared here on RCM, and those probably wiegh about 20-30lbs before converting them to electric. We all have to live our dreams, but I believe that this will cost you a lot mor than you may be willing or can even aford to invest. Good luck achieving your goal.