TwoWheelGuide

Repair guide

Fixing a puncture, and how often you really get one

The most useful repair there is. Fifteen minutes to learn, and it turns a ruined ride into a short stop at the roadside.

A mountain bike turned upside down at the roadside with its front wheel removed, tools, a bottle and a repair kit laid out on the ground beside it
From my own riding

How often this actually happens

Sharp roads do not automatically mean constant punctures.

Less often than you would expect

Glass and thorns are the two things that cut tyres where I ride, so you might reasonably expect to be fixing punctures every week. That has not been my experience at all.

Rough roads and sharp debris matter less than people assume. Tyre condition and running the right pressure do more to keep you rolling than the surface does to stop you.

Last reviewed: September 2026

A puncture is the one mechanical problem every rider meets. Done properly the repair takes ten minutes at the roadside, and the whole thing becomes an inconvenience rather than a phone call.

There is one step almost everyone skips, and skipping it is why people fit a new tube and puncture again within a mile. It is covered below, and it is the most important part of this guide.

What to carry

None of this is expensive, and all of it fits in a small saddlebag. A repair kit left at home has never fixed anything.

Check your valve type before buying tubes. Presta is the narrow one with a small nut you unscrew; Schrader is the wider car-style valve. They are not interchangeable, and the wrong tube will not fit through your rim.

The repair, step by step

1

Get the wheel off

Shift onto the smallest sprocket first if it is the rear wheel — it gives the chain the most slack. Open the brake if it is a rim brake, then release the quick release or undo the axle.

2

Let out any remaining air

Press the valve until the tyre is completely flat. A tyre with air still in it fights you at every stage.

3

Unseat one side of the tyre

Push the bead into the deep centre channel of the rim all the way round. This is what makes the tyre loose enough to lever off, and it is why people struggle when they skip it.

4

Lever the tyre off

Hook one lever under the bead and clip it to a spoke. Move a hand-width along and use the second lever. From there the bead usually runs off by hand. You only need one side off.

5

Take out the tube

Pull it out, leaving the valve until last so you do not bend it against the rim.

6

FIND WHAT CAUSED IT

Run your fingers slowly around the inside of the tyre — carefully, because it is usually something sharp. Check the outside too, and the rim tape. This is the step people skip.

7

Fit the new tube

Put just enough air in to give it shape. A limp tube twists and gets pinched under the bead; an over-inflated one will not fit. Seat the valve first, then feed the tube into the tyre all the way round.

8

Get the tyre back on

Work the bead on with your thumbs, starting opposite the valve and finishing at it. Push the seated part into the centre channel as you go and the last section will usually go on without levers.

9

Check the bead before inflating

Go round both sides and make sure no tube is peeping out under the tyre. Inflating over a trapped tube is a bang and a wasted spare.

10

Inflate and refit

Pump to the pressure printed on the sidewall, check the tyre sits evenly all round, then refit the wheel and close the brake.

Step 6 is the one that matters. If the thorn, flint or piece of glass is still in the tyre, your new tube punctures in the same place, usually within a few minutes of riding. Never fit a new tube without finding the cause first.

Reading the puncture tells you the cause

What the hole looks like, and what it means.
What you findCauseWhat to do about it
One small holeSharp object through the treadFind and remove it from the tyre
Two holes side by sidePinch flat — tyre squashed against the rimRun higher pressure, or wider tyres
Hole on the inner faceSpoke or damaged rim tapeReplace the rim tape; file any sharp spoke ends
A long slitSidewall cutThe tyre is finished; boot it to get home, then replace it
Hole at the valve baseTube moved inside the tyre, or a bad fitReplace the tube; check the tyre is seated evenly
Slow, repeated flatsSomething still embedded in the tyreSearch the tyre thoroughly, inside and out

Booting a cut sidewall

If the cut is big enough for the tube to bulge through, put something between tube and tyre to bridge it — a folded banknote, an energy bar wrapper or a proper tyre boot. Inflate slightly softer than usual and ride gently home. It is a get-home fix, not a repair: the tyre needs replacing.

Patch or replace?

At the roadside, fit the spare tube. It is faster, and you can patch the punctured one at home in comfort.

Patching properly works and lasts for years: find the hole, roughen the area with the sandpaper in the kit, apply a thin layer of glue, wait until it is touch-dry, then press the patch on firmly for a minute. The commonest mistake is not waiting for the glue.

Glueless patches are convenient and fine as a temporary fix, but they are less reliable long term.

A note on tubeless

Tubeless tyres carry liquid sealant instead of a tube, and most small punctures seal themselves before you notice. When one does not, you can plug it with a tubeless repair kit, or fit a normal inner tube to get home — which is why carrying a spare tube still makes sense even on tubeless wheels.

Getting fewer punctures

Pressure is covered in detail in the tyres and pressure guide, and the wider service routine is in the maintenance guide.

The short version

Three things that matter most

Find the cause first

The single step that separates a fixed puncture from a repeat one a mile down the road. Run your fingers inside the tyre, every time.

Carry the kit, always

Two levers, a spare tube and a pump. It fits under the saddle and it is the difference between a ten-minute stop and a lift home.

Pressure prevents most of them

Pinch flats are the most common puncture and the easiest to avoid. Check pressure weekly, not when it looks flat.

Puncture questions

Questions people ask about punctures

Ten minutes once you have done a few. The first time, allow half an hour and practise at home rather than learning at the roadside in the rain.

Replace at the roadside, patch at home. A properly glued patch lasts for years, so there is no need to throw a tube away for one small hole.

Almost always because whatever caused the first puncture is still in the tyre. Take the tyre off again and search it thoroughly, inside and out.

Only far enough to get off the road safely. Riding on a flat destroys the tyre, can damage the rim, and handling becomes unpredictable.

Nothing is puncture-proof, but puncture-resistant tyres genuinely reduce them. They are heavier and a little slower, which matters less on a commute than being late for work.

It is much easier with the wheel off. On a rear wheel it is worth learning the routine — shift to the smallest sprocket first and it drops out easily.

Keep reading

Related guides

Three more that pair naturally with this one.

Tyres & Pressure

Glass, thorns and heat – what actually finishes a tyre here.

Fixing & Maintenance

Punctures, brakes, gears and a maintenance routine that works.

Cycling in Morocco

Roads, drivers, water, heat and shops – what riding here is actually like.

Fewer punctures start with pressure

The tyres guide covers widths, pressures and when a tyre is worn out — the three things that decide how often this happens.

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