If you own a bicycle, it’s likely you will encounter a flat tire. Whether on the road, on the trail or at home in the garage, a flat can leave you frustrated and immobile. However, learning how to change a bike tube and fix a flat tire is a simple process and an essential skill that every cyclist should possess. Practicing changing a flat tire is a great way to boost your riding confidence and increase knowledge of basic bicycle repair.
Materials needed to replace a bicycle inner tube:
- Tire levers
- Spare tube and/or patches
- Adjustable wrench (necessary if you have bolt-on wheels)
If you got a flat while riding, you must first move to a safe place. You should be away from the road or trail. Flip the bike upside down; the seat and handlebars act as a makeshift workstand, supporting the bike and freeing your hands for the task. Remove the wheel from the frame. This requires loosening the axle nuts, quick-release levers, or though-axles which hold the wheels in place. You might also need to–open the brakes so the wheel can easily be removed.
If removing the rear wheel, first shift the chain to the smallest cog. This will make the removal and replacement of the wheel much easier. Once the wheel has been removed, completely deflate the tire, and use tire levers to gently pry one side of the tire bead over the rim of the wheel. This allows access to the tube without having to completely remove the tire. If replacing the tire, use the tire levers to pry the remaining bead over the rim, and then pull the tire off the rim.
Inspect your tire—inside and out—and remove any debris that might still be embedded in the tire. Failing to do so could quickly cause another puncture in your new tube.
Remove the tube, which might require removing a small washer on the valve stem. Inspect the tube, and locate the puncture in order to determine the cause of the flat. If only one hole appears on the outside of the tube, then the cause of the flat was likely some sort of road debris.
If one hole appears on the inside of the tube, it is possible the rim tape has shifted, exposing the sharp edges of the spoke below. Check the position of the rim tape, and adjust it, if necessary.
If two holes appear side by side, this is called a “pinch flat.” This occurs when an underinflated tire comes in contact with a hard surface that pinches the tube between the rim and the object. It causes two holes in the same location but on opposite sides of the tube. This is also commonly referred to as a “snake bite.” A pinch flat can be avoided by maintaining adequate air pressure in the tire.
Once the tube has been removed, it is time to install the new tube. This can be made simpler by adding a small amount of air to the new tube, giving it shape and preventing twisting during installation. Working your way around the tire, tuck the tube into the tire, and take care not to twist the tube.
Backroads Pro Tip
The direction of the tread pattern is often indicated by arrows on the sidewall of the tire. The arrows point in the direction of the wheel’s rotation.
Next, insert the valve stem and loosely screw the nut back onto the stem. This will help hold the tube in place and prevent the valve stem from falling out during the installation.
Reinstall the tire—first one side and then the other. Begin at the valve stem and work in opposite directions, ending at the point opposite the valve stem. You might have to use the tire levers to pry the last little bit of the tire bead up and over the rim.
Once the tire is seated in the rim, inspect around the tire to ensure that no part of the tube is pinched between the tire and the rim. If it is, gently push the tube and work the tire until the tube is completely inside the tire.
When you are confident the tire has been correctly installed, it is time to inflate the tire to the desired PSI. (This number is indicated on the sidewall of the tire.)
Reinstall the wheel on the bike, and be sure to close the brakes, if necessary, and you’re done!
Now that you know how to change a bike tube, even an unexpected flat can’t stop you from hitting the road!