How to Fix a Flat Tire | Tubeless
with JESSICA BROUSSEAU, Pro Mechanic for Liv Racing
It’s pretty rare to get a flat tire when you have a tubeless setup. The sealant inside your tires will quickly seal small holes and cuts to keep you rolling on the road or trail. However, flats are always possible – even with tubeless. Whether you’ve discovered your tire is flat after storing it in the garage, or you lose pressure after a sudden impact with a rock, we have you covered with the tips you need. Check out our guide to fixing your tubeless flat and getting back out on your ride.
What You'll Need
- Tire Levers
- Pump and/or CO2 with a valve
- Cloth or rag
You also might need:
- Tire boot
- Tire plugs
- Rim tape
- A tube (just in case!)
- Multi-tool (to remove your axle on some bikes)
Step by step guide to fixing a tubeless flat:
- Pull over to a safe place on the side of the road or trail.
- For tubeless mountain bike tires, first check to see if there is a small hole in your tire before removing it. If you have tire plugs, you can fix your flat quickly without removing your wheel or tire. Check out this video to learn how to use tire plugs.
- Shift! If you have a rear flat, shift into the smallest ring on your cassette. This will make the chain loose and will ensure your wheel is easy to remove and reinstall. If you have rim brakes, spread your brake pads by removing the cable tension or flipping the lever. If you are fixing a flat mid ride instead of at home, you can flip your bike upside down to remove the wheel(s). If you're worried about scrapes or scuffs on your handlebar tape and saddle, find a grassy area or ride with a rag in your jersey pocket. If you ride a mountain bike with hydraulic disc brakes, you might be worried about air finding its way into your brake lines. Usually, this is only an issue if you store your bike upside down for long periods of time.
- Remove the wheel from the bike. Remember, each bike can be different. We recommend practicing removing both your front and rear wheel from your bike so you are prepared when you get a flat. Generally speaking, the rear is always the wheel that gives you trouble. If you make sure you shift into the smallest ring on the cassette, it should make this easier. Then, remove the axle or loosen the quick release (but don't remove the nut!), pull the derailleur back and out of the way, and pull your wheel straight up and out of the dropouts.
- Remove the bead of your tire from the rim. For tubeless setups, this can be difficult. Squeeze hard on the tire and pull it away from the rim. Do this on both sides. Wiggle the tire back and forth to work the tire into the center of the rim will make it easier to remove the tire. Also, make sure all the air is out of the tire.
- Using the "spoon"-shaped end of the tire lever, pull the tire bead up and away from the wheel rim. Use the hook at the end of the lever and hook it to the spoke of the wheel.
- Using the second tire lever, insert the "scoop" end under the bead of the tire near the first tire lever you inserted. Pushing forward or pulling toward you, remove one side of the tire completely from the rim. (You may also do this with just one tire lever)
PRO TIP: Opt for plastic tire levers over metal ones. They won’t scratch the surface of your rim and they are lighter and easier to carry!
- Inspect the rim tape. Wipe down rim, checking to make sure the rim tape is intact with no holes. If there is a hole in the rim tape that is letting sealant and air through, you won’t be able to fix the problem trail-side. Throw a tube in (learn more about how to fix a flat tire with a tube HERE), and pedal home. When you get home, replace the rim tape. Learn more about how to apply rim tape HERE.
- Check the outside of the tire for holes and tears. Carefully run your fingers along the inside of the tire to check for gashes. Inspect the knobs on the tread of the tire as well. If you find a large hole or gash in the tire that cannot be fixed with sealant alone, you’ll need to patch the tire and you might even need to install a tube until you arrive home.
- If there is no damage to your rim tape or tire, add more sealant. Make sure you know how much sealant is required for your tires.
- Reinstall the tire on the rim. When you have most of the tire inserted into the rim, the last bit can sometimes be a bit of a pain.
PRO TIP: If the last bit is super tight, start back at the top and use your hands to wiggle the tire into the center of the rim. Just like you did at the beginning to loosen the bead from the rim, this creates extra slack in the tire and will make it easier to get onto the rim. While you wiggle the tire push down. When you get to the bottom, you might be able to pop that tire on with your bare hands!
- If the tire is still a bit tight, grab your tire levers again and flip it over to push the tire back onto the rim.
- Seeding a tubeless tire can sometimes be difficult trail-side. Using a CO2 cartridge can help. If you are home and have a floor pump, try pumping quickly to inflate. The trick is to keep pumping until you hear a “pop” which means the tire has seeded into the rim.
- Once the tire is inflated, shake, bounce and spin the wheel to ensure the sealant has coated the inside of the tire. For more tricks on tubeless setup check out our guide HERE.
- Reinstall your wheel. If you got a front flat, that is pretty easy. If you are fixing a rear flat, this is usually where people get caught up. No need to worry! Just remember, you already shifted into the smallest ring on your cassette, so that's where your chain should go. Also, remember that your cassette goes between the chains. Then, just move your derailleur back out of the way so your wheel can settle into the rear dropouts. Replace the axle/ tighten your quick release skewer and you're good to go!
- If you have rim brakes, don't forget to tighten the cable back down once your wheel is in. Then, just give it a spin and squeeze your brake to make sure everything works like it should. Nice job!