How to Change a Flat Bicycle Tire

Here's how to change out a flat inner tube and get your bike up & running again.

Difficulty: Moderate

Instructions

1. Got tools? For this job, you'll need a pair of tire irons and an end wrench or crescent wrench if you don't have a quick-release hub on the axle. Tire irons aren't absolutely necessary but will make it much easier to get the tire off the rim. You may also need a pair of pliers if you have difficulty removing the nail or other sharp object that caused the puncture.

2. Remove the wheel from the frame of the bike. If you have a quick-release hub, simply flip the lever open, loosen the nuts on each side a few turns and let the wheel come free of the dropouts. If you don't have a quick-release, loosen the nuts on each end of the axle with a wrench until the wheel easily comes free.

3. Remove the tire and tube from the wheel. Insert one tire iron under one side edge of the tire and pry it off the rim. Leave the top end of the tire iron under the tire and push the bottom end of the tire iron towards the spokes. Hook the notch in the bottom end of the tire iron onto a spoke and lock into place. Then take the other tire iron and insert it under the edge of the tire a few inches away from the first and pry another section of tire off the rim. Remove and re-insert near where the tire is coming off the rim and pry another section off. Continue around the wheel until one side of the tire is completely off the rim of the wheel. The other side can now be pulled off with your hands.

4. Remove the tube and check the tire thoroughly inside and out for the sharp object that caused the puncture. Do a visual inspection first. If you don't see anything, carefully feel the inside of the tire, slowly proceeding a few inches at a time, until you find it. Remove carefully so as not to injure yourself. Embedded glass or a broken-off nail or staple may require pliers to remove completely.

5. Inflate the new tube slightly. Dust with corn starch (if desired) and set the new tube into the tire.

6. Install the tire onto the wheel. Find the valve hole in the wheel and set it over the valve of the tube such that the valve inserts into the wheel. Then push one side of the tire onto the rim all the way around. Make sure the tube is pushed up into the tire all the way around before attempting to push the other side of the tire onto the wheel. When you get about a third of the tire onto the rim it will start to get tight and you'll be tempted to reach for a tire iron to pry it on. This is a bad idea as you could pinch the tube with the tire iron and have to change it all over again. Instead push with your thumbs and patiently work the edge onto the rim. When it is finally on and seated, check again to be sure the tube is pushed well into the tire and situated properly.

7. Inflate the tire to its recommended pressure. Make sure the bead of the tire gets seated onto the rim as it inflates. Listen for a popping sound that indicates the bead of the tire is catching the rim and seating itself properly. Work the bead into place with your thumbs if necessary. Deflate.

8. Install the wheel on the bike and inflate tire to its recommended pressure. Good to go!

Tips & Warnings

• If your bike has a quick-release mechanism on its brakes, be sure to use it before removing the wheel. It will loosen the brake cable and allow the brake pads to open slightly, thus letting the tire pass through much more easily. Just remember to re-engage the brakes after re-installing the wheel! Recommended pressure for bike tires should appear on the sidewall of the tire.