Bead tires is the term for the tire edges that sit on wheels. Wheels for cars, bicycles, etc. Made with a small slot or groove in which the tire bead sits. When the tire is properly inflated the air pressure inside the tire makes the bead in this groove.
It is common among drivers of off-road vehicles to reduce air pressure in their tires. This makes the tread tread spread, creating more surface area for the tire tread to grip the terrain. If the pressure is too low, there may not be enough pressure to keep the bead on the wheel, causing the bead to erupt from the wheel; this is often referred to as "bead loss". Beadlocks, which are clamped beads on wheels, are often used in this case.
Often, the bead may become frozen to the edge after rusting occurs, requiring the use of the bead breaker.
Video Tire bead
References
Source of the article : Wikipedia