I've been doing some research and can't seem to find a decent answer, CAN YOU repair sidewall cracks with urethane glue like windshield calking or a super glue like GOOP or Gorilla glue? both stay flexible and are somewhat water proof. Inflate tires so that the glue dries without putting stress on the crack once air is in them. Tires hold air and I will be using tubes but the cracks are not only UGLY but also may catch on a rock or root and rip wide open. I just don't feel justified on spending twice what the machine is worth on tires.