Where is the tyre bead?

The bead runs around both inner edges of the tyre where the tyre meets the wheel. Once the tyre is correctly fitted and inflated, most of the bead is hidden by the rim.

What is the tyre bead made from?

The bead area contains strong reinforcement, traditionally including high-tensile steel bead wires encased in rubber. Its construction helps the tyre remain securely seated on the correct rim under inflation pressure and normal driving loads.

Why is the bead important?

• It locates the tyre correctly on the wheel rim.
• It helps maintain the seal between a tubeless tyre and the wheel.
• It transfers forces between the tyre and wheel during acceleration, braking and cornering.

What can cause a tyre bead to leak?

Air loss around the bead can be caused by corrosion or contamination on the rim’s bead-seat area, damage to the wheel, damage to the tyre bead, or an incorrect tyre/rim fit. The source should be identified rather than simply inflating the tyre repeatedly.

Can a damaged bead be repaired?

Damage to the bead is safety-critical because this area secures the tyre to the wheel. A tyre with significant bead damage should be inspected by a tyre professional and should not be assumed repairable. Bead damage can also occur during incorrect fitting or removal, which is why suitable tyre-fitting equipment and procedures matter.

Related guides: inner liner, tyre casing and tyre shoulder.