Originally Posted by pugo

mate, you have a serious geometry problem there, do you understand the principles of a kart chassis???????

it works via stub to king pin inclination vs castor.......the principle is simple you turn the wheel left and the left front wheel becomes lower in the chassis causing a weight shift to the front right wheel, this lifts the left hand rear thus enabling the the thing to turn round the corner (no diff, solid rear axle) if you do not lift the inside rear when turning it will go straight on.
looking at the length of the chassis you have 2 choices, you are going to have to stiffen massivly your 3 rails probably needing to add another 2 at least, and increasing the castor dramatically...........or........fit a diff unit

this is the reason prokarts and gearbox karts are 4rail+ and use really thick tubing you simply cant pick the rear inner up with a lot of weight on it on an old 100 chassis

HTH

Pugo