How to Fix a Puncture in Bicycle Tyre

For the cyclist, one thing is inevitable – you will get a puncture or flat tyre at some time. This is something that can easily be fixed, but there are some basic skills you need to master

The Puncture Repair Tool Kit you will need

Before you can fix a tyre, punctured or not, you need the correct tool kit. These are not huge items, and you can get a little saddle bag to stow them in. The tool kit should have the following items in it:

The right pump to inflate the kind of valve that is fitted to your wheels. There are two main types of valve: Presta or Schraeder.
Tyre levers, these are used to lift the tyres off the metal rim of the wheel rim
A patch kit, with extra patches, rubber cement, and a piece of sandpaper or a buffer
A small piece of tough fabric like canvas to place underneath a big gash in the tyre, this should be about one inch square
A spare tube or two – this should have the same type of valve as your existing tyre
If your wheel does not have quick-release levers you will need a 15mm spanner or adjustable spanner
A small pocket knife or screwdriver to release air from Schraeder valves

Fixing the Flat Tyre

Remove the wheel from the bike.
Use the tyre levers to pry the tyre off the rim. Do not use screwdrivers or knives to do this as it can damage the tyre or the wheel. Make sure you keep one bead of the tyre on the rim. This will help you to keep the tube and wheel aligned.
The tube should be pulled most of the way out of the tyre, starting opposite the valve. Make sure you remove the sharp object that caused the puncture or flat. If you are just going to put on a new tube, go to step 8.
Inflate the tube slightly using the pump and look around the tyre or an obvious hole. Sometimes you will be able to hear the air escaping or feel it with your finger. If you cannot find the puncture, remove the tube entirely from the wheel submerge the tube in a bowl or bucket of water. You will be able to find the hole as there will be bubbles of escaping air from the puncture.
When you find the puncture, scrape the area around it with the small sand paper or rough edged buffer to clean the rubber and roughen it so that the patch adheres properly. Cover the area with some rubber cement from the repair kit and make that the area covered is larger than the patch. You will then have to wait about 5 minutes for the cement to dry.
While the cement is drying, remove the sharp object that caused the puncture. If there is a large cut in the tyre, use the fabric square between the tube and the tyre under the hole to keep new debris from lodging in the hole and puncturing the tube again.
When the cement is dry, peel the silver foil off the patch and apply that side to the tyre. Press hard from the centre toward the edges so that it sticks really well.
Next we have to put the tyre back on the wheel rim. Inflate the tube slightly and pack it back into the tyre, starting at the valve. Squeeze the bead of the tyre back into the rim of the wheel; you may need to use tyre levers to complete this. Inflate the tube a little more and make sure that the bead is within the rim all the way around. If it has slipped out anywhere your tube will be squeezed against the rim and will burst; you will then have to replace it with a new one.
Before fully inflating the tube, put the wheel back onto the bicycle forks. When the wheel is fully in place, inflate the tyre to the same pressure as the other tyre on the bike. Do not use car-style air pumps available at filling stations; they are meant for larger tyres and deliver air more quickly, which could burst your tube. Before you finish, tighten the bolts that hold the axle onto the bike by turning and flipping the quick-release levers or with your spanner.