If you have a tire that's leaking from the bead, break the tire from the wheel and clean the bead, then reseat the tire. IF it still leaks, the bead may actually be damaged. Break it down again, liberally coat the bead area with silicone, and reseat the bead. Lower the tire pressure to less than four pounds until the silicone has set up. You should then have a leak-free bead.