<P> Tubeless tires or tyres (in some Commonwealth Nations) are pneumatic tires that do not require a separate inner tube . </P> <P> Unlike pneumatic tires which use a separate inner tube, tubeless tires have continuous ribs molded integrally into the bead of the tire so that they are forced by the pressure of the air inside the tire to seal with the flanges of the metal rim of the wheel . </P>

A sudden loss of air pressure in a tire is known as a