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Important: Always read and follow the operating instructions.
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 ini-
tial 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 asymmet-
rical 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 auto-
mobile tires is between 24 and 45 PSI. Light truck inflation pressure
typically covers a wider range.
Air flow through valve requires about
140 PSI air pressure drop to ensure
sufficient flow on difficult tires.
Usually last to “pop” is the mount side.
Requires visual
conformation of
bead seat.
Stand clear of the tire during bead seat and inflation.
Stand clear of the tire during inflation.
Requires rubber lubri-
cant on both upper
and lower beads.
Make sure the tire bead is
not obstructing air flow
from the valve stem
into the inside of
the tire.
