The following program calculates the stress in the rear axel of the go kart. Often the rear axel will get bent due to various loadings.
You will notice that the data put into the program is “close to failure.” What this means is that the chances of bending the shaft are very high, especially if the go kart is to be ridden over rougher style terrain.
To get the shaft to not fail play with the width of the gokart frame (or supports). You will see that the wider the frame, the less the stress. However, going wider with the frame adds weight and other problems, not to mention handling and center of gravity issues….