How to Mount and Seat a Tire Safely

Step 1 of 7

Match and Inspect

1. Match the diameters. Never put a tire on a rim unless you have positively identified both and the diameters match. A 16 in tire goes on a 16 in rim, never a 16.5.
2. Never mount a passenger car tire on a motorcycle rim. The bead seat and flange are different.
3. Inspect the wheel and parts. Bent, pitted, cracked or broken parts must not be used. Tag them unserviceable and take them out of the work area.
4. Replace damaged or leaking valves.
5. Wear eye protection and work with the right tools, never a cheater bar on tire irons.

Step 2 of 7

Deflate Completely

1. Remove the valve core and let all the air out before you demount. Never demount a tire unless you're sure it is fully deflated.
2. Truck multi-piece wheels: if the tire ran at 80% or less of its pressure, or the wheel may be damaged, deflate it with the core out before you take it off the axle.
3. Run flat or underinflated steel cord radial truck tires can have hidden sidewall damage. Inspect them in a safety cage as USTMA describes before you put them back in service.

Step 3 of 7

Lubricate the Beads

1. Use a non-flammable tire mounting lubricant on the tire beads and the rim mating surfaces, unless the tire maker says not to.
2. Never use antifreeze, silicone or petroleum based products as a mounting lube.
3. Never use starter fluid, ether, gasoline or anything flammable to lubricate or seat beads, and never ignite anything in a tire to seat it.

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Step 4 of 7

Mount From the Narrow Side

1. Mount and demount from the narrow ledge side of a single piece wheel, the side nearest the drop center well.
2. Lock the wheel down on the tire machine per the machine maker's instructions.
3. Keep the bead in the drop center as you work it over the flange. Forcing it can damage the bead, and a bead damaged tire can explode during mounting or fail later.

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Step 5 of 7

Seat the Beads: 40 PSI Max

Never go over 40 psi to seat beads, unless the tire maker gives a different limit. That holds even in a safety cage.

1. Use a clip-on air chuck with an in-line valve and a gauge or presettable regulator, and enough hose to stand clear.
2. Stand clear. Never stand, lean or reach over the tire and wheel while it is inflating.
3. Lock it down or cage it. Seat beads with the wheel locked on the machine, or in a safety cage or other restraining device.
4. Not seated by 40 psi? Let all the air out, reposition the tire, re-lubricate and try again.
5. Check both sides to be sure the beads seated evenly.

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Step 6 of 7

Inflate to Pressure

The trajectory is any path a part could travel if the assembly lets go, which isn't always straight out from the wheel. Stay out of it.

1. Single piece truck, bus, trailer, tractor and off-road wheels must be inflated in a restraining device, behind a barrier, or bolted on the vehicle with the lug nuts fully tightened (OSHA 1910.177). Multi-piece wheels go in a restraining device; see step 7.
2. Keep a foot of clearance. Don't inflate if a flat, solid surface in the trajectory is within one foot of the sidewall.
3. Never go over the maximum pressure on the sidewall unless the tire maker recommends it.
4. Don't rest or lean any part of your body or equipment on the cage while inflating.
5. Tube type tires: once the beads seat, let the air out and re-inflate so the tube can settle without folds.

Step 7 of 7

Split Rims and Lock Rings

Multi-piece rims are covered by OSHA 1910.177 and need specific training. The key rules:

1. Deflate with the valve core out before you demount, and before you remove the wheel from the axle if the tire ran at 80% or less of its pressure or may be damaged.
2. Match the parts. Don't mix rim components except as the rim matching charts or the rim manual allow.
3. Lubricate the bead and rim mating surfaces with rubber lubricant unless the maker says not to.
4. Outside the cage, inflate only enough to seat the bead on the ledge and make an airtight seal. Do the rest in the restraining device.
5. Check the rings in the cage. If they aren't seated and locked, let the air out with the core removed before you adjust anything.
6. Never hammer or force a side ring or lock ring while the tire has pressure in it.
7. Never weld, braze, heat or rework a cracked, broken, bent or damaged rim part, and never apply heat to a multi-piece wheel.
8. Stay out of the trajectory the whole time.