The big roller tire gives younger riders advantages that adult size bikes are getting wider tires along with a new tread design allows for maximum traction and stability in many riding conditions this leads to more fun and better confidencecasing 60tpibead wirecompound 60a20 x 28quot max ride 25psi max install 35psi approximate weight 670g24 x 28quot max ride 25psi max install 35psi approximate weight 835g