How to: Fix a Flat Tire
One: determine if you really have a leak. Tires will lose air over time. If you have not used your bike in a while, then what you think is a flat may only be the natural tendency of the rubber to lose air. Fill the tire and listen for air escaping. If it does not go down in 24 hours, you probably do not have a puncture.
Two: Check the outside of the tire for penetrating objects. Look for glass, tacks, nails etc. If you are unsure put a little spit or water on the suspicious area and look for bubbles.
Three: Pull the tire off the rim. You will need at least two tire levers. These are plastic 'spoons' that slip under the bead of the tire and allow you to pry the tire away from the rim without harming the inner tube. Slip one under the bead and carefully pry up. Hook the lever on a spoke and move about an inch or two down the tire and start with the second one. You can usually then slide the lever around and remove the tire. However with some really tight tires, a third lever may be necessary. Do not use a screwdriver. You will give yourself a flat. Many mountain and hybrid tires will not require the use of levers at all.
Four: Check the inside of the tire for objects. Carefully run your fingers around the inside of the tire and feel for glass shards or pieces of metal. Go around at least two or three times so as not to miss anything.  
Five: Locate the hole in the tube. If it is small, then you can patch it. If you found no objects in the tire and your tube has two slits on the side running parallel to each other, this is a 'snakebite' or pinch flat. It comes from either not having enough air in the tire or from really hitting a sharp object really hard. Rim damage is another product of this kind of flat. Note the location of the hole in relation to the tire. If the hole is on the bottom (next to the rim), then your rim strip or tape may need replacing. A large hole with jagged edges (usually associated with a loud bang!) is usually not patchable. The tire is probably no good either. However, in a pinch, a folded dollar bill can be used to fill the hole to get you home. If you ride a lot, carry a piece of casing cut out from an old tire to fill the hole. Most folks will put a new/repaired tube in at this point and ride on. When they get home they will patch the puncture and use it as the spare.  
Six: To patch the tube you will need glue, patches, and an abrasive like sandpaper. Most patch kits come with all of the above. Just be sure that if you have had the kit for a while that the glue has not dried out. Lightly scuff up the area around the hole with the sandpaper. The idea here is to clean the tube of oils and other stuff that would hinder the glues ability to work. You can also use a mild solvent like acetone. Be sure the area you clean is larger than the patch.
Seven: Apply a small glob of glue on the hole and with your pinky, smear it around to an even area. Try and keep the hole in the center so you know where it is. (If you inflate the tube a bit while the glue is wet, it will often mark the hole with a bubble making it easier to find.) The glue is a contact style cement, so a little bit goes a long way. Now go find something else to do for about five minutes. You want the glue to be tacky and not wet before you apply the patch. Otherwise it will not work.
Eight: To apply the patch, hold it by the cellophane and carefully peel the foil part away. Try not to touch the sticky side of the patch as oil from your hands will reduce the glue's ability to bond. Place the patch (sticky side down) onto the glued area of the tube. Place it carefully as once it touches the glue you cannot pull it away without destroying the bond. Using a tire lever, rub the patch into place. It will be set almost immediately. If the glue does not contact the patch completely, you will probably not get a good seal. It also helps to have the tube pumped up to roughly the size it will be in the tire. This helps to prevent the patch from stretching too much. You can peel the cellophane off if you wish, but it is not necessary.  
Nine: To reinstall the tube, give it just enough air to give it shape and place it inside the tire. Place the valve into the rim hole and begin to push one of the tire's beads over the rim. This should be done by hand. When one side is done, go back to the valve and begin to slip the other bead over the rim. When you get to the last part, it will get tight. You may need to slip a tire lever in under the tire bead and push it up and over the rim. Be careful as not to pinch the tube. When the tire is on the rim go back to the valve and push it into the tire. This ensures that the tube is completely inside the tire and will not 'pop' out when inflated. Fill the tire with about 20 to 30 psi and visually inspect to see that the bead is not rising above the rim. If it is, let the air out and push the tire away from the rim. You will probably see a bit of the tube sticking out. With your fingers, 'roll' the tire around until the tube is inside the tire. We recommend the use of talc in the tire. This keeps the tube from sticking to the tire and may reduce future flats. It also leaves an April fresh scent.  
Ten: Ready to go! If you have a lot of problems with flats, there are some ways to reduce the likelihood. You can put an additive in the tube like Slime. This will seal small punctures on the outside of the tube. In most cases, it will not seal a pinch flat. Tire liners can be put between the tire and the tube. They help prevent penetration into the tube. They cannot prevent a pinch flat and a big nail could get through, although usually not before you find it. Both of these solutions had a bit of weight to the bike. In many cases just using a good tire will solve a lot of your problems. Continental, IRC, and many other companies make tires that have a tight weave and are harder to get through. Still confused? Stop in, e-mail us, or give us a call. Perhaps we can diagnose what your problem is.

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