To patch a tire you need

• Bicycle inner tube
• patch
• Tire lever
• Mounting fluid
• Roughener

Cost: around 10 euros.

Step 1: Remove the wheel

To patch the tire, the wheel must first be removed. If the hub is fastened with quick-releases, simply fold them down. Otherwise, use a wrench to loosen the nuts. Then remove the wheel from the fork.

Step 2: Lever out the tire

Use a tire lever - it is made of plastic and must not have any sharp edges - to lever the casing out of the rim. Be careful not to damage the inner tube even more.

Step 3: Retract the inner tube

Unscrew the valve cap and the nut that secures the valve to the rim. Push the valve out of the opening, then pull off the inner tube piece by piece.

Step 4: Find the hole

Inflate the inner tube firmly, then listen to where the air escapes. Another trick: place the tube in water and see where bubbles appear. Mark the hole with a ballpoint pen.

Step 5: Roughen the rubber

To ensure that the rubber is not too smooth for the patch, slightly roughen the tube with a small metal plate (included in the patch box) where the hole is.

Step 6: Glue the repair patch on

To repair the inner tube, stick the repair patch to the damaged area and press it on firmly. The aim is not to press it on for as long as possible, but to press it evenly all around and over the edges of the hole.

Step 7: Insert the hose

Push the valve back through the opening. Then inflate the tube very slightly and carefully push it under the casing, piece by piece, until it lies underneath.

Step 8: Give it a helping hand

If the casing can only be pulled on with great force, use the assembly fluid to help. It can lubricate the inner tube, allowing it to slide a little better into the correct position on the rim.

Mending tires: This makes the repair even easier

• Puncture sniffer: This is a small tin with polystyrene balls. If you hold it over escaping air, the balls move. This allows you to see exactly where the hole is in the tube. Available in outdoor stores (e.g. Globetrotter) for approx. 3 euros.
• Sandpaper: If you don't have a roughener to hand for mending bikes, you can also use some coarse-grained sandpaper on the inner tube.
• Latex milk: This special liquid is very good for repairing bicycle tires with small tube holes from thorns or thumbtacks. Available for approx. 6 euros, e.g. from Amazon.