A puncture is not a breakdown — it is a fifteen-minute pause, once you have done it twice. Here is the method, in the order that actually works at the roadside.
Carry these four things
- A spare inner tube (the right size — it is written on your tyre sidewall, e.g. 700×28c)
- Two tyre levers
- A mini pump or CO₂ inflator
- A patch kit as backup for the day you puncture twice
The 15-minute method
- Get the wheel off. Rear wheel? Shift into the smallest cog first — the wheel drops out far more easily. Open the quick release or undo the thru-axle.
- Unseat one side of the tyre. Hook a lever under the bead, anchor it on a spoke, slide the second lever around. Leave the other side of the tyre on the rim.
- Find the culprit. Pull out the tube, then — before anything else — run your fingertips slowly around the inside of the tyre. The thorn or glass shard that caused the puncture is usually still embedded, waiting for your new tube. This single step prevents most “double punctures”.
- Fit the new tube. Put a little air in it first so it holds a round shape, seat the valve, tuck the tube into the tyre all the way round.
- Re-seat the tyre by hand. Work the bead back onto the rim with your thumbs, finishing opposite the valve. Avoid levers here if you can — they pinch new tubes.
- Check, then inflate. Squeeze the tyre all round to make sure the tube is not trapped under the bead, inflate to the pressure range printed on the sidewall, refit the wheel.
Make the next one rarer
Most commuter punctures are preventable. Tyres with a puncture-protection belt (the commuter classics) are slower on paper and infinitely faster than walking. Check your pressure weekly — soft tyres pinch-flat on potholes. And replace a tyre when you can see the casing threads: rubber that thin stops nothing.
Riding through winter? Glass and grit season makes protection tyres even more worthwhile — more in our winter riding guide.