(11) Stages of Inflation on a Conventional Tire and Rim
Review these descriptions and diagrams carefully. Refer to them as necessary during bead sealing, bead seating, and inflation to
verify that you are proceeding properly and safely.
Bead Sealing
Bead sealing is the process of capturing air pressure between the tire and the rim. The tire will usually contain about 1/2 to 2 PSI
at initial bead seal.
Bead Seating
Bead seating usually occurs on the long tapered side of the wheel first and the shorter side last. Bead seating will usually require
at least 7 PSI in the tire. 40 PSI is the maximum safe pressure at this stage regardless of tire operating pressure. Most European
import cars and many aftermarket alloy wheels are very tight and can be difficult to bead seat. Also note that asymmetrical hump
and run-flat tires are extremely difficult to bead seat. Follow tire manufacturer’s recommended procedure for bead seating.
Inflation
After the beads are seated, the tire is ready to be inflated. Do not inflate the tire above the manufacturer’s recommended pressure
as stamped on the tire sidewall. The typical inflation pressure for automobile tires is between 24 and 45 PSI. Light truck inflation
pressure typically covers a wider range.
