Flat tire: how to fix it roadside

Flat tire: the repair every cyclist must master

Flats happen to everyone. Even with puncture-resistant tires, even with tubeless. The good news: with the right gear and technique, you can be rolling again in 5 to 10 minutes. Here's how.

What to always carry

CO2 vs mini pump: CO2 inflates in 10 seconds (convenient), but you only get one shot per cartridge. Mini pump is unlimited but takes 5 minutes of pumping. Our advice: bring both.

Method 1: tube change (most common)

Step 1 — Remove the wheel

• Rear wheel: shift to smallest cog, open quick release (or unscrew thru-axle), lift derailleur, remove wheel.
• Front wheel: open quick release, remove wheel.

Step 2 — Remove the tire

1. Fully deflate the tube (press the valve)
2. Insert a tire lever under the tire bead, opposite the valve
3. Hook it to a spoke
4. Insert the second lever 10 cm away and slide it along the rim
5. One side of the tire pops off — only remove one side

Step 3 — Inspect

Before installing the new tube, run your hand inside the tire to find what caused the flat (thorn, glass, wire). If you don't remove it, you'll flat again immediately.

Step 4 — Install the new tube

1. Slightly inflate the new tube (just enough to give it shape)
2. Insert the valve into the rim hole
3. Tuck the tube under the tire all around, being careful not to pinch it
4. Push the tire bead back on by hand (no tire levers for remounting — pinch risk!)
5. Check that the tube isn't poking out anywhere

Step 5 — Inflate

• Road: 6-8 bar (85-115 PSI)
• Gravel: 3-5 bar (40-70 PSI)
• MTB: 1.5-2.5 bar (20-35 PSI)

Method 2: patch (backup)

If you've already used your spare tube and flat again:

1. Find the hole: inflate the tube and hold it near your face to feel the air
2. Sand the area with the kit's abrasive paper
3. Apply glue, let dry 2 minutes (it should become matte)
4. Press the patch firmly for 1 minute
5. Reassemble

Method 3: tubeless plug

If you run tubeless and sealant hasn't sealed:

1. Don't remove the tire — locate the hole
2. Insert a plug with the insertion tool
3. Cut excess plug material
4. Reinflate
5. Sealant finishes sealing around the plug

The plug lasts thousands of kilometers. It's a permanent repair.

Common mistakes

1. Using tire levers to remount — you'll pinch the new tube
2. Not finding the cause — you'll flat again 500 m later
3. Inflating fully at once — check the tube isn't pinched first
4. Forgetting alignment — tube poking out = blowout when inflating

L'Atelier helps you find the right inner tube for your wheels (size, Presta/Schrader valve, diameter). Ask your question and get a sourced answer.