Change Your Flat Tire
What you will need:
Tire Tools
The Procedure:
1. Release the brake as shown in the pictures, so there is plenty of brake pad/tire clearance to remove and replace the wheel.
Releasing Linear Pull Brakes
Linear Pull Brake Fully Released
Road Brake in Riding Position
Road Brake with Brake Released
2. Remove the wheel from the bike. Before removing a rear wheel, shift to the smallest cog. That makes it easier to reinstall the wheel.
3. Release the remaining air in the tube. Use the non-hooked end of the tire tool to pry under the bead of the tire. If you will reuse the tube, be careful not to pinch a hole in it. On rear wheels, it is usually easier to remove the bead on the nondrive (left) side.
4. Firmly move the tire tool around the rim of the wheel until one side of the tire is separated from the rim of wheel. If you need more support, hook the first tire tool to a spoke and use your second tool to remove the tire.
Usually you will not take the whole tire off the wheel, but only one side. This allows you to remove the tube while the tire is still half on, making it easier to reinstall the tire.
5. Remove the tube with your hands.
6. Now that you have the tube out, inspect the rim and the tire to make sure that whatever caused the flat will not puncture your new tube.
Adhered to the rim should be a rubber or clothe rim strip between the bottom of the tube and the inside of the rim, to prevent friction holes. Does the rim strip effectively cover all the spoke nipples?
Is a thorn or piece of glass embedded in the tube? It may help to inflate the old tube, find the hole, and find the place on the tire corresponding with the hole. We carefully run a finger over the inside of the tire, trying to find embedded stickers. (It is easy to cut yourself during this step, so be very careful.)
7. We recommend you use a new tube. Patching tubes is an iffy proposition. To help prevent pinching a hole in your new tube, put enough air in it to give it a little shape, but not enough to make it too hard to reinstall the tire.
Place the tube in the tire with the valve through the rim's valve hole. Remember, the tire should be half on the wheel--that is, it should have one bead still in the rim. If you have taken the tire entirely off the wheel, place one of the beads on the rim so that the tire is half on. Work the tube into the tire.
8. Now reinstall the tire on the wheel by maneuvering the remaining tire bead over to the inside of the rim. Be careful not to pinch a hole in the tube. With some tires, this is a hard job. Try not to use the tire tool to reinstall the tire, since the tool is more likely to pinch a hole in the tube. Hold the wheel with the uninstalled bead away from you, and use your fingers to pull the bead over the rim.
9. Replace the wheel on the bike. Be sure you understand how to connect any quick release device. Inflate to the proper psi. Reattach the brake release. Rotate the wheel while watching the brake pads. Make sure the brake pads properly contact the rim and that they do not touch the tire. Be sure the tire does not rub anything. Make sure that the tire bead properly connects with the rim--sometimes the bead will pop over the rim, exposing the tube, which is very unsafe.