How to Fix a Puncture: Step-by-Step Guide

Punctures happen to everyone. Here's a clear, no-nonsense guide to fixing one at home or on the road — plus advice on when it's better to replace the tube entirely.

What you'll need

• Tyre levers (2 or 3 plastic levers)
• Pump (track pump at home, mini pump for the road)
• Patch kit or a new inner tube
• Bowl of water (optional — helps find small holes)

Step 1: Remove the wheel

If it's the rear wheel, shift to the smallest sprocket first — this makes removal and refitting much easier.

• Release the brake (V-brakes: unhook the noodle; disc brakes: no need)
• Open the quick-release lever or undo the axle nuts
• Lift the wheel out of the dropouts

Step 2: Remove the tyre and tube

• Let out any remaining air by pressing the valve
• Hook a tyre lever under the tyre bead and clip it to a spoke
• Slide a second lever along to unseat one side of the tyre
• Pull the inner tube out, starting opposite the valve
• Push the valve through the rim hole last

Step 3: Find the hole

Inflate the tube and listen carefully. You can usually hear the hiss. If not:

• Water method: submerge sections of the inflated tube in a bowl of water and look for bubbles
• Hand method: pass the inflated tube slowly past your lips — you'll feel the air on wet skin
• Mark the hole with a pen or by pinching it

Step 4: Patch or replace?

When to patch

• Single small hole (thorn, glass, wire)
• Hole is away from the valve and seams
• You have a patch kit and time

How to patch

• Rough up the area around the hole with the sandpaper from the kit
• Apply a thin, even layer of vulcanising glue slightly larger than the patch
• Wait 2–3 minutes until the glue is tacky (not wet)
• Press the patch firmly onto the hole — hold for 30 seconds
• Peel off the backing film

When to replace the tube

• Multiple holes or a large tear
• Hole near the valve stem
• Tube is old, thin, or has been patched several times
• You're on the road and need a quick fix

Step 5: Check the tyre

This step is critical. Whatever punctured the tube may still be embedded in the tyre. Run your fingers carefully around the inside of the tyre, feeling for:

• Thorns, glass shards, or wire poking through
• Cuts or splits in the tyre casing
• Sharp edges on the rim tape (can cause pinch punctures)

Remove anything you find. If the tyre has a large cut, you can use a tyre boot (or a folded section of an old tyre or even a banknote) as a temporary liner.

Step 6: Reassemble

• Put a small amount of air in the tube — just enough to give it shape
• Push the valve through the rim hole first
• Tuck the tube into the tyre all the way around, making sure it's not pinched or twisted
• Push the tyre bead back onto the rim with your thumbs — start at the valve and work both ways
• The last section will be tight — use tyre levers carefully if needed, but avoid pinching the tube
• Inflate to the pressure printed on the tyre sidewall
• Refit the wheel and reconnect the brake

Common mistakes

• Not checking the tyre — the same object punctures the new tube immediately
• Pinching the tube during refitting — causes an instant flat (pinch puncture)
• Under-inflating — soft tyres are more prone to pinch flats and rim damage
• Over-inflating — can blow the tyre off the rim (dangerous)

How to prevent punctures

• Keep tyres inflated — check pressure weekly
• Use puncture-resistant tyres — Schwalbe Marathon, Continental Gatorskin, etc.
• Fit tyre liners — a plastic strip between tyre and tube that blocks thorns
• Use sealant — tubeless setups or sealant in inner tubes seals small holes automatically
• Avoid riding in the gutter — that's where glass and debris collects
• Replace worn tyres — thin, bald tyres puncture more easily