How To: Patch a Flat Bike Tire

It's bound to happen sooner or later: you have a flat. Before you go walking your bike back home, however, you should first attempt to repair it. Using nothing more than a basic tire patch kit, here's how to patch a flat bike tire.

What You'll Need

The only items you'll need to repair a bike tire is a tire patch kit and portable air pump, both of which are sold at most bike shops. The tire patch kit should contain a small piece of rubber, glue/adhesive, and a metal scraper that looks like a cheese grader. Double check the kit to make sure it contains these items. If not, you'll have to purchase them separately.

Remove the Blown Tire

Some bikers may attempt to repair blown tires by leaving the tire on the frame, but this isn't recommended. Find a safe, flat area where you can remove the tire from your bike, as this will make the process easier by offering greater accessibility to the tire.

Find the Leak

You can't expect to patch a blown tire unless you know exactly where the leak is coming from. If the tire was pierced by a screw or nail, you should be able to identify the source of the leak simply by looking for the protruding metallic object sticking out of the tire. But if small debris caused the hole -- or if the nail/screw fell out -- this isn't an option.

To determine the source of the leak, pump the blown tire with air and place your ear next to it. Move your ear around the rubber until you hear the characteristic "fizzing" sound of air escaping. Once you've identified the source of the leak, move on to the next step.

Prepare the Area

Prepare the site of the leak by rubbing it with the metal scraper. This will smooth the area so the rubber patch fits more snugly against the tire, minimizing the risk of air leakage. Even small imperfections in the tire rubber may allow air to escape through the patch, negating all of your hard work. Smooth the surface around the leak by rubbing it with the metal scraper, at which point you can proceed to the final step.

Patch it

The final step is to apply the patch. It's recommended that you read and follow the instructions that came with your tire patch kit, but this usually involves placing a small amount of glue/adhesive on the hole and then pressing down with the patch. After holding the patch in place for 5 or so minutes, it should become firm, although you may still want to wait a little while before riding on it just to be on the safe side.