What You Need Before You Start
Changing a bicycle tire tube takes about 15 minutes once you have the right tools. You will need a new tube (the correct size for your wheel — check the sidewall of your tire or your bike's manual), two tire levers (plastic or metal tools that pry the tire bead away from the rim), and a pump. A patch kit is optional but useful if you get a second flat before you reach home.
Before you begin, flip your bike upside down so it rests on the handlebars and seat, or use a bike stand if you have one. This keeps the wheel accessible and stable. Remove the wheel from the frame — for the front wheel, open the quick-release lever or unscrew the axle nuts; for the rear wheel, shift to the smallest cog, open the quick-release, pull the derailleur back, and lift the chain off the cog.
Key Takeaways
- You must remove the wheel from the frame before you can access the tire and tube.
- Deflate the old tube completely, then use tire levers to pry one side of the tire bead away from the rim so you can pull the tube out.
- Before installing the new tube, check inside the tire for thorns, glass, or sharp objects that caused the flat.
- Inflate the new tube partially by hand or pump before seating it fully, so it does not twist inside the tire.
- Reinstall the tire bead by hand first, then use the pump to finish inflating and seat the bead evenly on both sides of the rim.
Deflate the Old Tube and Remove the Tire
Press the valve on the old tube to release any remaining air. If the tube has a Presta valve (the thin, pointed kind), unscrew the small nut at the top first. Once the tube is flat, insert a tire lever under the tire bead — the edge of the tire that sits on the rim — about 6 inches away from the valve. Pry gently until the bead lifts over the rim edge.
Slide the tire lever around the rim to free one full side of the tire. You do not need to remove the entire tire, only one bead. Once one side is loose, reach in and pull the old tube out, starting at the valve. If the valve is glued or welded to the rim (some rims have this), work carefully to avoid damaging the rim.
Inspect the Inside of the Tire for Damage
Before you install the new tube, run your fingers slowly along the inside surface of the tire. Feel for thorns, glass shards, sharp wire, or anything else that might have caused the flat. Even a tiny piece of glass will puncture the new tube when ready. If you find something, remove it with tweezers or a small knife.
Check the tire bead and the rim tape (the strip that covers the spoke holes) for damage. If the rim tape is torn or missing, the spoke ends will puncture the new tube. You can wrap electrical tape or duct tape around the rim as a temporary fix, but proper rim tape is better. If the tire itself has a large cut or bulge, it needs to be replaced — a new tube alone will not fix it.
Install the New Tube
Check the valve type on your new tube and make sure it matches your rim. Schrader valves (the fat, car-tire kind) and Presta valves (thin and pointed) require different rim holes. Inflate the new tube by hand or with a few pump strokes until it holds its shape — it should feel slightly puffy but not fully firm. This prevents the tube from twisting inside the tire during installation.
Insert the valve through the rim hole first. Then tuck the tube evenly inside the tire all the way around, making sure no part of it is pinched between the tire bead and the rim. Start at the valve and work your way around in both directions, smoothing as you go. The tube should sit flat and centered inside the tire.
Reseat the Tire Bead on the Rim
Use your hands to push the tire bead back onto the rim, working your way around the wheel. Start opposite the valve and work toward it from both sides. You should be able to seat most of the bead by hand without tools. If the last section is tight, use a tire lever gently — do not pry hard, as this can pinch the new tube.
Once the bead is seated all the way around, the tire should look even on both sides of the rim with no bulges or dips. If one section looks higher than the other, the bead is not fully seated. Deflate slightly, adjust the tube position, and reseat that section by hand.
Inflate to the Correct Pressure
Inflate the tire slowly to about half the recommended pressure (you will find the range printed on the tire sidewall). Stop and check that the bead is seating evenly on both sides of the rim. The tire should look symmetrical, and you should see a thin line where the tire meets the rim all the way around. If the bead is uneven, deflate, adjust, and try again.
Once the bead looks even, inflate to the full recommended pressure. For a Presta valve, screw the small nut at the top closed after you finish inflating. Reinstall the wheel on the frame, making sure the axle is fully seated in the dropouts (the slots on the frame that hold the wheel). Tighten the quick-release or axle nuts firmly.
Common Mistakes to Avoid
The most common error is twisting the tube inside the tire during installation. This creates a weak spot that will fail within a few miles. Prevent this by inflating the new tube slightly before you install it and by tucking it evenly all the way around the tire.
Another frequent mistake is missing the object that caused the first flat. If you do not remove the thorn or glass, the new tube will puncture in the same spot. Take time to inspect the inside of the tire carefully. A third error is pinching the new tube with a tire lever while reseating the bead. Use your hands as much as possible and only use a lever if absolutely necessary — and use it gently.
Finally, do not over-inflate or under-inflate. Check the pressure range on your tire sidewall and use a pump with a pressure gauge. Under-inflation causes the tire to roll sluggishly and can pinch the tube (called a pinch flat); over-inflation makes the ride harsh and can blow the tire off the rim.
Frequently Asked Questions
How do I know what size tube to buy?
The size is printed on the sidewall of your tire in a format like "700x25c" or "26x1.95". Write this down or take a photo before you go to the shop. Tubes are labeled by wheel diameter and width range, so a 700c tube fits 700c wheels, and a 26-inch tube fits 26-inch wheels. Width tolerance is usually wide — one tube often fits a range like 25–32mm.
Can I patch the old tube instead of replacing it?
Yes, if the hole is small and you have a patch kit. Clean and dry the area around the hole, roughen it with the sandpaper in the kit, explore glue, wait the time specified on the kit (usually 3–5 minutes), and press the patch firmly for 30 seconds. Let it cure for 5 minutes before inflating. Patches work well for small punctures but are less reliable than a new tube for large holes or valve damage.
What if the tire bead will not seat on the rim?
The bead may be stuck or the rim may be dirty. Deflate completely, clean the rim edge with a dry cloth, and try again. If it still will not seat, the tire may be too large for the rim or the rim may be bent. Check that the tire size matches the rim, and inspect the rim for dents. A bent rim usually needs professional repair.
Do I need to remove the wheel to change a tube?
Yes, you must remove the wheel to access the tire and tube. You cannot change a tube while the wheel is on the frame. The only exception is if you have a very quick-release system designed for roadside repairs, but even then you will need to remove the wheel.
How long does a new tube last?
A tube lasts until it gets a puncture, which depends on road conditions and how carefully you ride. Most tubes last months to years of regular use. Tubes stored in direct sunlight or extreme heat degrade faster. Keep spares in a cool, dry place and check them before long rides.