As soon as you get that “sinking” feeling or hear the hiss of escaping air, let your ride partners know you have a flat (so they won’t disappear over the horizon) and stop. If it’s a rear flat, shift onto the smallest rear cog. The first step in wheel removal is opening the brake (photos), which makes it easier to get the wheel out.

Open sidepull brakes by fully rotating the little lever on the brake upwards (a).

Open linear-pulls (also called V-brakes) by lifting the end of the noodle out of its holder (b).

While it’s possible to get the flat tire through the brake without opening it, it won’t be so easy reinstalling the wheel when it’s fully inflated. That’s why we recommend opening the brake first.

If you have disk brakes, there’s nothing to open. The wheel will come right out of the brake with no muss, no fuss.

Open the quick release (or loosen the axle nuts) on the wheel with the flat and lift the bike to remove the wheel. To extract rear wheels, it helps to pull the derailleur back slightly to clear the axle parts as the wheel passes through (main photo).

For fronts, you’ll probably need to hold one side of the quick release and turn the other counterclockwise to create clearance to get past the wheel-retention tabs on the fork (inset photo).

Never force the wheel out! If it’s stuck, determine what’s holding it in place and free it.

When the wheel is removed, lay the bike on its left side so you don’t damage the derailleur or get dirt in the drivetrain.

Remove the valve cap (not shown) and nut (sometimes found on Presta valves: inset photo). For Presta valves, unscrew the tip (inset photo) and press down to let all the air out. For Schraders, poke the end of your tire lever into the valve to release all the air. Starting directly opposite the valve, wiggle a tire lever beneath the tire edge (called the “bead”) and pry down to lift. If possible, hook the lever on a spoke (many levers are made to do this), or hold it in place. Place another lever about 6 inches away from the first and pry here (main photo). Continue with your third lever until you can get one side of the tire off. Then reach inside and extract the tube. Pull the other side of the tire off the rim or pry it off with your levers.

If you have trouble getting the tire off, make sure all the air is out of it. Even a little air can make the tire a lot tighter.

Some cyclists prefer to remove only one side of the tire to ease reinstallation. The disadvantage is that it’s harder to check inside the tire to find whatever popped the tube.

It’s important to find whatever caused the flat and remove it. If you don’t, the sharp item might still be in the tire where it’ll just pop your new tube. To find it, remove your glove (or use a rag), and run it around inside the tire in both directions (photo). If something sharp is still stuck in your tire, it’ll snag the glove. Remove it. If you can’t find anything, it probably got knocked out during the disassembly procedure.

Check inside the rim, too, to ensure the rim strip covers the nipples and anything else sharp.

As long as the hole in the tire is about 1/4-inch long or less, it’s okay to reuse it.

If the tire has a large gash in it, simply place a dollar over it as you reinstall the tube. It’ll reinforce the tire at the hole and get you home. Replace the tire ASAP (don’t forget to save the dollar!).

Place the valve partway into the hole and simultaneously push the part of the tire bead that’s at the valve and closest to your legs onto the rim. With both hands moving downward away from the valve, finish working the bottom tire bead (the one closest to your legs) onto the wheel all the way around. If it won’t fit onto the rim, check that the valve is inside the tire, not trapped beneath the bead.

With one bead in place, tuck the tube fully inside the tire and on top of the rim, which will cause the other bead to rest flush against the rim. Work this bead on, starting at the valve as you did with the first. You may have to push the valve into the tire to provide clearance for the bead. Once you’ve got it started, work your hands away from the valve pressing the bead onto the rim around the wheel.

With a few inches of bead left to pop onto the rim, the tire will resist. Let all the air out. Crouch and rest the wheel on your knee to have something to push against. Now, hold the bead in place with one hand and with your stronger hand, push down to roll the stubborn section onto the rim with the heel of your hand (main photo). But don’t try to pop it on all at once. Install an inch at a time, moving your hand along until you’ve fully installed the tire. Got it? Way to go!!

Tubes that are slightly narrower than the tire fit fine and are easiest to install (for example: use a 700 x 20c tube in a 25c tire and a 1.5-inch tube in a 1.9-inch tire).

A trick to create slack and ease tire installation is to go around the rim squeezing the tire beads into the rim’s center (the deepest portion).

If you locate the tire label at the valve, you’ll have a reference point when searching the tire for what popped the tube.

Place your pump on the valve and inflate the tire. To prevent valve damage, brace it by wrapping a finger behind a spoke (photo left) so you’re pushing against your hand, not the valve. Inflate the tire until it’s just firm (not fully inflated). At this point, inspect the tire to make sure it’s “seated,” which means that it’s sitting correctly on the rim.

If the tube gets trapped beneath a bead (photo top), inflating further may blow the tire and tube off the rim! There’s a bead line on the side of the tire (photo bottom) that should be equidistant from the rim all the way around on both sides of the tire. If it’s not, or if you see a section of tube peeking out from under the rim, let the air out, work the tube back into place, reinflate partway and check the tire again.

When it’s seated correctly, inflate it fully. Install the valve nut (if your tube uses one) and cap finger tight (overtightening the valve nut can damage the tube and make it difficult to loosen it when you need to fix a flat).

Reinstall the wheel in the frame, close the brake quick release or reattach the noodle or cable and you’re ready to ride!