A tool for seating a tubeless tire on a rim using pressurized gas includes a cylindrical pressure vessel with a pistol grip extending radially from the tank. The tool includes a rapid opening gas valve positioned between the cylindrical pressure vessel and a nozzle. In some embodiments the nozzle includes a jet configured to receive pressurized gas from the cylindrical pressure vessel into a chamber of the nozzle so that as the stream of gas enters the chamber, the Venturi effect causes air to enter the chamber through air intake ports and the stream of gas and air from the air intake ports is blown out of the outlet of the nozzle. The tire is seated on the rim by positioning the system so that the air from the nozzle rapidly blows into the tire between the bead of the tire and the rim upon the valve being opened.