I agree with Christian. we run cadets and seniors in LO206 on MG reds. They work well and provide usable grip down to the cords. When designing a race car or kart the first question asked before you design anything is “What tire will be used?” the design grows from that. No race kart is designed to be run on concession tires. You need enough grip for the chassis to work. They run Vega Blues in SoCal and they are good, more grip than the reds and probably bordering on a little too much grip for the low power engine. Hoosiers are really high grip for them but I have heard that Hoosier is coming out with a new tire for the low horsepower classes.