Ask a Mechanic: Installing a Tire Boot

Emily wants to know, “I sliced my tire so badly the other day that even if I had put a tube in, I might not have made it home without a flat. Can you show me how to boot a tire?

Of course we can, Emily. Whether it’s caused by a nail, glass, or rocks, we’ve all been stuck with a sliced sidewall before. Luckily, using or installing a tire boot is relatively easy to do.

If you’ve sliced your tire’s sidewall deeply, then you likely have a flat as well, so you’ll have to replace the tube.  Start by shifting your rear cassette into its highest gear, switching off any clutch derailleurs, and removing your rear wheel. Next, remove one side of your tire’s bead and remove the bad tube from the wheel. Make sure to locate the large hole or slice in your tire before moving forward.

If you’re running tubeless tires and sealant, you’ll want to make sure and clean the inside area around the rip or tear as well as you can.

Inflate your new tube with about 5 psi and then slide the tube into the tire as you would if you were simply changing a flat. This time however, before reseating your tire’s bead you’ll install a tire boot. Now, you may be wondering, “what is a tire boot anyway?” The answer is just about anything. If you have a tire repair kit, it’ll likely have a tire boot in it. If you’re a bit more unprepared, you can use an empty energy gel packet that’s folded in half, a folded bill, or if you’re really desperate, a credit card. Get creative with it.

Once you have your boot of choice selected, simply slide the boot between your tire and tube directly underneath the rip or tear. At this point, having a little extra air in your tube will help to keep the boot in place. After the boot is in the tire, go ahead and seat your second tire bead with your hands or a tire lever and inflate to normal psi.

Should the boot shift upon inflation or if it wasn’t installed correctly, you’ll have to remove the tire bead and adjust the boot as necessary. Although this process may take a few tries to get right, it’s much better than an embarrassing phone call to a coworker or a long walk home.