HOW TO FIX A FLAT TIRE
Simple tips & tricks to doing it quickly
If you’ve never had a flat tire, you haven’t ridden a bicycle much. It’s just something that will happen when you ride. Off-road riders seem to get them more, from thorns and pinch flats on the trails, but commuters will have them at least occasionally.
CHECK YOUR TIRES
Before each ride, check both the condition of your tires and the air pressure. If your tires are worn (i.e., if the tread is worn off or if there are cracks or wear in the sidewalls), it’s time to replace them. Without the tread, the tires can be very slippery in many conditions and can cause you to wipe out. They also have less protection against thorns and other jagged objects you may run over on a ride. If the sidewalls give out, you will have a flat that can’t be fixed on the road.
Check the air with a reliable gauge. Though you can get an idea of your tire pressure from a good floor pump, there are some great purpose-made digital gauges that can give you an accurate pressure reading. Many have both types of valve attachments—Schrader and Presta.
If you own a bike, you need to have a few essential items to deal with your tires. You’ll definitely need a pump, but it’s better if you have two. Go to your bike shop and get a good floor pump, as it’s the fastest and easiest way to pump up your tubes. Most will have both types of valve attachments. While you’re there, pick up a smaller pump you can always carry with you, and make sure it’s the right type for your bike’s valve style. Some can mount on bottle-cage bosses for your frame, and others can be carried in a pack or a seat wedge.
As an alternative, if you’d rather, you can carry a CO2 cartridge pump with you. These fill tubes quickly and effortlessly, but you will have to carry a couple of cartridges with you.
There are some leaks that can’t be patched, so a spare tube is a must-have. Make sure you always have spare tubes in the right size for your bike. Have at least one at home and one that you carry on the bike or in a pack you always take.
A good patch kit can be a lifesaver on a ride. The advantage is that patching a tube means you don’t have to take the wheel off of the bike. If your bike doesn’t have quick-release hubs, this means you’ll also have to carry that size wrench with you to remove the wheel, which can be heavy and take more time. If it’s the tire on a bike with a hub drive, you’ll also likely have to disconnect the quick-disconnect on the wire leading to the hub. Check your owner’s manual about orientation of connectors, axles, etc. in this case. There are times it can make a difference (e.g., a BionX wheel has a slot that must face straight down when you reinstall the wheel so the system can calibrate correctly).
FINDING THE LEAK
If you can find the leak, often you’ll be able to find the thorn or puncture hole. If you know where the leak is to start, patching will be easier. If you don’t know where it is, sometimes you can pump up the tire and spin it slowly to listen for the leak. If you still can’t find it, you’ll have to take the tube off, which means taking the tire off and taking the tube out.
Once you have the wheel off, fully deflate the tire using the valve. Then take the tire bead off the rim. This can be done with fingers, which is safest, but if you need extra leverage, you can use a tire lever. A set of tire levers, usually the plastic ones are thebest and lightest, is another thing to consider carrying with you.
Insert one of the levers under the bead, then pry it back and hook the other end on a spoke to hold it in place. Then, put another lever in a few spokes down the line and pry it back. Taking care not to nick the tube, slide this lever around the rim to pull the bead over the rim all the way around. Then pull the valve out of the valve opening in the rim. With Schrader valves, this can be done easily by just pushing it through. With Presta valves, there’s usually a nut threaded down on the valve, and you’ll have to unscrew that and set it aside, then you can push it through the hole.
Remove the tube and inspect it. If it’s a really small hole that you can’t see, pump some air into the tube. A cursory check can be done running your hand over the tube, but some leaks are small enough that your hand may not feel it. Hold the tube up by your face and hold the tube near your lips (not touching) and rotate the tube around until you feel it. Your lips have more nerve endings than your hands and will feel the air escaping from the tube easily.
An alternate to that is submerging the tube, a part at a time, in a sink filled with water. You’ll see the bubbles escaping where the leak is. You’ll then have to fully dry the tube before patching it.
Before you do anything else, mark the hole with a marker or ball-point pen. This will make finding it again much easier, even after you rough up the surface.
Self-adhesive patches are the easiest, and you never find that your rubber cement is all dried up when you need it most. Thanks to the X, you can center this on the puncture, then burnish it down smooth with a thumbnail.
There are two types of patch kits. One is the old-fashioned kind, with patches, rubber cement and either a metal grater or a piece of coarse sandpaper (e.g., 150 grit). The other kind forgoes the rubber cement in favor of self-adhesive patches. You’ll need to rough up the surface of the tube for the patch to stick. Make sure the rough area is larger than that of the patch. Then apply rubber cement and let it dry and apply the patch, or apply a self-adhesive patch. Here’s where that pen mark comes in handy; you will know where to center the patch. Nothing is worse than patching a tube, only to find that the leak is right on the edge of the patch!
After that, inflate the tube lightly to make sure the patch is on correctly and sealed. Then you can put it back into the tire, use your fingers and re-seat the tire bead, then pump the tire up carefully, watching that the bead is seated evenly. Pump the tire up enough to check, then deflate it fully. This helps ensure you’re not folding or pinching the tube anywhere. Then re-inflate it, checking the bead again. If you’ve done this right, you’ll have a patched tube that can be used for a long time. If you patch a tube more than once, though, it’s time to replace it when you get home.
Installing a new tube is the same process, including inflating, checking, deflating, re-inflating, and checking again.
DOLLARS AND SENSE
If your tire is worn, especially the sidewall, you’ll need to replace the tire as soon as possible. If you’re riding trails and something slashes a small hole in your sidewall, you’ll need to patch that so the tube doesn’t protrude and ultimately explode with a loud bang. You’ll first have to let the air out of the tube, then pry the tire bead off the rim. You need something sturdy to help the sidewall in its effort to hold in the tube. We’ve seen guys use used Gu packets, large tire patches or even dollar bills. American paper money is actually not paper but a type of fabric (75-percent cotton and 25-percent linen), and as such it can be a good temporary patch to keep your sidewall from blowing out.
Once you’ve ensured your tubes and tires are ride-worthy, you’re ready to be back on the road. You have the tools to keep going, so you don’t have to walk your bike all the way or call a friend to come get you. With a little practice, you can fix a flat with no sweat in a couple of minutes. Having the right stuff on the ride comes in handy; we often run into people with a flat who are unprepared. It’s always good karma to stop and help someone get back up and running. You never know when that favor will be returned down the road!