How to inflate tubeless tyres and seat the bead at home

Short answer: to inflate tubeless tyres and seat the bead, take the valve core out, wet both beads with soapy water or mounting fluid and centre the tyre in the rim well. Then pump hard with a track pump until both beads pop onto the rim shoulders. Stop at the lower of the tyre's and the rim's maximum pressures. If the beads will not seat, a booster pump or a compressor delivers the air faster; CO2 is a last resort that Schwalbe and Continental advise against.

Top-up or seating: check the bead before you pump

A tyre that has gone soft but still sits on the rim shoulders needs a top-up. A tyre that has gone flat enough for a bead to drop into the rim well, or a tyre you have just fitted, needs seating. The two jobs use the same pump and a different sequence.

For a top-up, leave the valve core in: open the Presta tip, press the pump head on, pump to your riding pressure and close the tip. Our bike tyre pressure guide and the tyre pressure calculator give the figure.

For a flat tyre, look at both sides first. If the moulded line above the bead has dropped behind the rim edge anywhere, treat it as a seating job. A tyre that seats and then keeps going down is covered in our guide to a tubeless tyre losing air.

Before you inflate a tubeless tyre

Start from an assembled, compatible wheel: a tubeless-ready tyre on a tubeless rim, taped, with the valve fitted. Continental says to check rim, tyre, valve and tape for damage before mounting. Taping and valve fitting are in our guide to setting up tubeless tyres; the TLR marks and hookless approval lists are in bike tyre sizes.

The kit is a track pump with a gauge and a head that seals on a Presta valve with the core removed, a valve core tool, a rag, and sealant with a syringe if the tyre is dry inside. Add a bead lubricant: Schwalbe sells Easy Fit with a sponge applicator, and Stan's uses soapy water.

How much pressure does it take to seat a tubeless tyre?

There is no seating pressure, only a ceiling: the lower of the tyre's maximum and the rim's maximum. Schwalbe says that if the rim's stated maximum is lower than the tyre's, the rim's figure must not be exceeded. Continental says the lowest value is the one to follow; Stan's says not to exceed either stated pressure.

Find both figures before you start: the tyre's range on the sidewall, the rim's limit in the wheel maker's manual or on a rim decal. Hookless rims cap it at the ETRTO maximum, which ENVE gives as 5 bar (72.5 psi) for 25–29 mm road tyres and Giant uses as its threshold.

Makers differ on how close to go. Park Tool inflates to at least the label maximum to seat the beads; Topeak's booster manual says never to exceed it. The safe reading is up to the lower limit if you need it, not one stroke past it.

How a tubeless bead seats, and what the pop proves

A fitted tyre starts with both beads in the rim well, the deepest part of the rim bed. Air has to lift each bead onto its shoulder, and until the bead touches the rim wall, air escapes around it. Seating happens when air arrives faster than it leaks out.

That is why every maker's instruction is about the speed of the air rather than a higher gauge reading. Schwalbe asks for "a strong blast of air" from a floor pump, compressor or booster, and Stan's removes the valve core for "a quicker burst of air".

The beads announce themselves. Schwalbe says the tyre "snaps audibly into place", and BikeRadar listens for pings until the tyre is seated around the full circumference. A pop is not proof, though: DT Swiss says the tyre must contact the rim evenly around its entire circumference, and Stan's says to check the bead seat line.

That line, moulded just above the bead, should sit the same distance from the rim edge all the way round, on both sides. Cyclist's test is to look for any point where the tyre pinches in.

Which pump seats a tubeless tyre?

A track pump seats many tyre and rim combinations once the core is out and the beads are wet. A booster pump or a compressor is for the combinations it does not, and a hand pump is for topping up a seated tyre.

• Track pump (floor pump). Schwalbe lists it first for the first inflation and Silca calls it the most preferred method. Muc-Off adds the limit: high-volume 29er mountain bike tyres may hold too much air for a track pump to produce the rush.
• Hand pump. None of the maker instructions opened for this guide names one for seating. Use it to top up a seated tyre, core in.
• Booster or charger pump. A chamber you fill, then release in one burst. Topeak's JoeBlow Booster manual charges the chamber to 160 psi (11 bar); that is the chamber's pressure, not the tyre's, and the same manual says not to exceed the tyre's maximum.
• Compressor. Stan's says one may be necessary for some tyres and Park Tool calls it highly recommended. Use a Presta head and a gauge, read the pressure with the air stopped, and keep the same ceiling.
• CO2 cartridge. Muc-Off says a CO2 inflator seats the bead instantly. Silca calls it the last resort because CO2 lowers the sealant's pH; Schwalbe says not to use CO2 at all, Continental does not recommend it with sealant and Stan's says it degrades liquid latex. Muc-Off's sequence avoids the conflict: seat dry, deflate, add sealant, reinflate with a pump.

How to inflate and seat a tubeless tyre step by step

This order gives a track pump its best chance before anything stronger comes out: air path clear, beads centred and wet, core out, then speed.

1. Check the valve and the air path

Stan's says the tyre beads must sit either side of the valve hole, not over it, and Schwalbe says the valve must be between the beads when inflating. Tighten the valve nut by hand only: Stan's says pliers tear the rim strip, and DT Swiss gives a limit of 0.5 Nm. Check that the pump head seals on the valve.

2. Centre the tyre in the rim well and wet both beads

Push both beads down into the centre channel all the way round, as Stan's instructions describe, and centre the tyre before inflating, as Schwalbe's fitting guide says.

Wet the beads where they meet the rim. Schwalbe says to coat both beads with assembly fluid so they slide into position; Stan's uses soapy water, Cyclist a sponge of washing-up liquid solution, and Silca a heavy soap mixture or a little sealant on the bead.

3. Take the valve core out

Unscrew the core with the core tool and put it somewhere safe. Schwalbe, Stan's, Muc-Off and Silca give the same reason: with the core out, more air passes through the valve per stroke.

4. Pump hard and fast, watching the gauge

Fix the pump head over the empty valve stem and, in Muc-Off's words, pump as hard and as fast as you can until you hear the pop. Cyclist describes the moment as a couple of quick pumps, then the tyre catching onto the rim seats.

Stop if the gauge nears the lower maximum without a pop, if a bead lifts out or the tyre bulges, or if air hisses out at the rim all round. Topeak's rule for its booster is the same: if inflation fails, deflate and check tyre, rim and valve.

5. If it will not seat, deliver the air faster

Re-wet the beads, recentre the tyre and try once more. If the beads still will not lift, switch to a booster pump or compressor, or use the inner tube method below.

6. Check the bead line on both sides

Turn the wheel slowly and look at the moulded line above the bead on each side. A section that sits low is not seated. For a low section, Park Tool's instruction is to deflate, break the bead at the low point, lubricate it with soapy water and reinflate.

7. Add sealant, refit the core and inflate again

Muc-Off's order after the pop: release the air, add the sealant, replace the core and reinflate. Schwalbe gives the same sequence for Doc Blue. The amount is the sealant maker's figure for your tyre, covered in our guide to tubeless tyre maintenance.

Continental says to put the valve at about 5 or 7 o'clock when adding sealant so it flows into the tyre. A bead can drop back into the well as the tyre deflates, so check the line again after the second inflation.

Park Tool says to spin the wheel and rock it to spread the sealant to the beads, and Continental recommends a short test ride straight after installation. Set your riding pressure, then check it the next morning.