It happens to us all. Once you've calmed down, stopped jumping up and down and cursing and stopped throwing things around, you'll still need to fix that bad boy. This page will help you do that. There are 3 ways to fix a flat. Take it to a bike shop, patch the inner tube or install a new tube. If you're ready to tackle the task yourself, we recommend you install a new tube. Patching tubes is not very reliable. Unlike many years ago when tubes were made of mostly natural rubber, today's tubes are made of synthetic rubber. The glue required to do the job right is harmful to you and to the environment, and it's replacement is lacking in it's ability to always provide a good seal. However, if you don't have a new tube handy, you will have no choice so we explain how to do it below.
You will need several items to do the job right.1 - An adjustable wrench to remove the wheel if you don't have a quick release wheel
2 - A set of tire irons to remove the tire. They are usually sold in a set of 3
3 - A spare inner tube
4 - A patch kit for tire repair if necessary
5 - A pump or other source of air
6 - An ink pen (yes, an ink pen - you'll see)
Let as much of the air out of the tire as possible. The less air in the tube, the easier it is to remove. The tip of a phillips screwdriver works well, or you can use a corner of a tire iron.
Step 2 Illustration
Step 2Working on the part of the wheel furthest from the valve, hold the tire away from the edge of the rim with your thumb and insert the spoon shaped end of a tire iron with the curved edge facing the tire. Note: if tire sticks to the edge of the rim, it's best to break that 'seal' all the way around the tire on both sides first by pressing the tire away from the side of the rim with your thumbs. Slide the tire iron up under the tire just enough that it won't slip out.
Step 2a Illustration
Step 2aYou should now be able to slide the iron around the edge of the rim gradually releasing the tire until you have completely circled the rim. At this point, the half the tire facing you should be off the rim.
Step 2b Illustration
Step 2bIf the tire is real tight, you can lock the other end of the tire iron around one of the spokes and repeat this step with a second tire iron starting about 2 or 3 inches from the position of the first tire iron. Make sure that the first one is tucked up under your arm or hold it in place with your other hand so that if it breaks free, it won't fly up into your face.
Step 3 Illustration
Step 3Hold the wheel so that you're looking at the area where the valve goes through the rim. Starting from the part of the wheel furthest from the valve, start removing the tube. When just the valve remains in the rim, press the tire out of the way with your thumb. Take an ink pen (told ya) and mark a circle on the side of the tire and on the side of the tube itself where the valve goes through the rim. This is an important step in that it will help you locate the cause of the flat. With the tire still pressed out of the way, slide the valve out of the rim.
Step 5 Illustration
Step 5Now that you know where the hole is located on the tube, you can find what caused the flat. At this point most people will tell you to run your finger around the inside of the tire to find it, but that's kind of silly. If the flat was caused by a small nail or most likely a piece of glass, you'll cut your finger. But you were smart enough to mark the position of the tube in the tire with a circle, so let enough air out of the tube that it takes it's normal shape. Lay the wheel on a flat surface with the open side of the tire facing you, making sure the circle you made on the tire lines up with the valve hole. Lay the tube on the wheel with the tube in it's original position as indicated by the circle by the valve.
Step 5a Illustration
Step 5aFind the circle you marked around the hole in the tube. Now mark an X on the side of the tire at the location of the hole. Now you know exactly where to look for what caused the flat without causing bodily injury.
If the hole is on the outside of the tube or along one side of it, inspect the tire thoroughly inside and out around the area where you marked the X until you find the culprit or the cut or hole it left. Take your time with this inspection. With today's 'knobby' style tires, small pieces of wire and glass have plenty of places to hide. If the hole was on the inside edge of the tube, inspect the rim for any sharp points or spokes poking through. If you still can't find what caused the flat, check out Other possibilities.
If the hole or cut in the tire is very small, you can skip to If the hole is relatively small, you can put a patch inside the tire and move on. If it's too large to patch effectively, get yourself a new tire and proceed to Part 2. If the problem is on the wheel rim itself, grind down the spoke or file down the imperfection.