What you need before you start

Changing a bike tire requires a few tools and materials you should have on hand. You will need two tire levers (plastic or metal tools that pry the tire off the rim), a new inner tube or a patch kit if you are repairing the existing one, and a pump. Some people also carry a small wrench if their wheel does not have quick-release levers. Check that your new tube matches your tire size — the size is printed on the sidewall of your tire, usually something like 26 x 2.0 or 700 x 35c.

Before you begin, lay your bike on its side or use a bike stand to keep it stable. Remove any fenders or brakes that might block access to the wheel. If the flat is on the rear wheel, shift to the smallest cog on the cassette first — this gives you more room to work.

Key Takeaways

  • Remove the wheel by opening the quick-release lever or unscrewing the axle nuts, then use tire levers to pry the tire bead away from the rim.
  • Pull out the old inner tube completely and inspect the inside of the tire for thorns, glass, or sharp objects that caused the flat.
  • Insert the new tube by first inflating it slightly so it holds its shape, then seating it evenly inside the tire all the way around.
  • Reinstall the tire bead by hand first, then use the heel of your hand to roll it onto the rim, checking that the tube is not pinched between tire and rim.
  • Inflate the tire to the pressure printed on its sidewall, then reinstall the wheel and test the brakes before riding.

Removing the wheel from the frame

Open the quick-release lever on the axle by flipping it outward, or unscrew the axle nuts by hand or with a wrench if your bike does not have quick-release. On the rear wheel, pull the derailleur back and lift the chain off the smallest cog. Lift the wheel out of the frame and set it on the ground.

If you have rim brakes (caliper or cantilever), you may need to open the brake lever or unhook the cable to create enough clearance. Disc brakes usually do not interfere. Once the wheel is free, lay it flat on a clean surface so the tire does not roll away.

Prying the tire off the rim

Insert a tire lever under the tire bead — the edge of the tire that sits on the rim — about six inches from the valve stem. Pry the bead up and over the rim edge. Hook the other end of the lever to a spoke to hold it in place. Insert the second lever about twelve inches away and repeat, then work your way around the wheel, spacing the levers evenly as you go.

Once one side of the tire is completely off the rim, pull out the inner tube. Check inside the tire carefully for thorns, glass shards, or sharp objects. Run your fingers slowly along the inside surface, or wrap a rag around your finger and feel for anything that sticks out. If you find the cause of the flat, remove it. If you do not find anything, the puncture may have come from a pinch flat (the tube was squeezed between the tire and rim) or a slow leak from a valve problem.

Installing the new or repaired tube

If you are using a new tube, check the valve type — it should match your rim. Presta valves are narrow and have a small nut at the top; Schrader valves look like car tire valves. Inflate the new tube slightly, just enough so it holds its shape and is not completely flat. This makes it easier to seat evenly inside the tire.

Insert the valve stem through the rim hole first. Then work your way around the wheel, tucking the tube inside the tire all the way around. Make sure the tube is not twisted and sits evenly. This step prevents pinch flats when you reinstall the tire bead.

Seating the tire back onto the rim

Start opposite the valve stem and use your hands to roll the tire bead back onto the rim. Push the bead down and inward with the heel of your hand, working your way around the wheel in both directions toward the valve. The last section, near the valve, will be tight — this is normal. Use steady pressure rather than jerking motions.

As you work, check frequently that the tube is not pinched between the tire and rim. Look at the bead line — a thin groove that runs around the tire — and make sure it sits evenly on the rim all the way around. If you see a section where the bead is higher or lower than the rest, stop and work that section again. Do not use tire levers to force the bead on; if it will not go by hand, the tube may be pinched or the tire may not be seated correctly.

Inflating and reinstalling the wheel

Once the tire is fully seated, inflate it to the pressure printed on the sidewall. Start with a few pumps, then check the bead line again to confirm it is still even. Finish inflating to the correct pressure. If you over-inflate, let some air out by pressing the valve.

Reinstall the wheel by reversing the removal steps. On the rear wheel, pull the derailleur back and guide the chain onto the smallest cog, then seat the wheel in the frame. Close the quick-release lever or tighten the axle nuts. Reconnect the brakes if you disconnected them. Spin the wheel to make sure it does not rub on the frame or brakes, then test the brakes by squeezing the lever — the wheel should stop smoothly without locking up.

What to do if the tire keeps going flat

If you get another flat in the same tire within a few rides, the cause is usually still inside the tire. Remove the wheel again and inspect the inside more carefully, using a bright light. Feel along the rim tape — the strip that covers the spoke holes — to make sure it is not torn or missing. A damaged rim tape lets the tube contact the sharp spoke ends.

If the rim tape is damaged, you will need to replace it. If you keep finding no visible cause, the problem may be a slow leak from the valve itself. Try a different tube in the same tire. If the new tube also leaks, the issue is the tire or rim, not the tube. If the new tube holds air, the original tube had a slow puncture you could not see.

Frequently Asked Questions

Can I patch a tube instead of replacing it?

Yes, if the puncture is small and you have a patch kit. Clean and dry the area around the hole, roughen it with the sandpaper in the kit, apply the adhesive, wait the time specified on the kit, then press the patch firmly onto the hole. Patch kits work best for punctures smaller than a pinhole; larger holes or valve damage usually means replacing the tube.

What if I cannot get the tire bead back on by hand?

Stop and check that the tube is not pinched. Deflate the tire slightly, work the pinched section free, then try again. If the bead still will not seat, the tire may be too tight for the rim, or the tube may be the wrong size. Never force it with tire levers — you risk damaging the tire or pinching the tube further.

How do I know what pressure to inflate to?

The correct pressure range is printed on the sidewall of the tire, usually something like "80–100 PSI" or "2.5–3.5 bar." Use the lower end if you ride on rough terrain or want more grip; use the higher end if you ride on smooth pavement or want less rolling resistance. Check the pressure with a pump gauge before every ride.

Do I need to replace the tire if it has a hole?

Not necessarily. Small punctures in the tread can be patched from the inside using a tube patch kit. If the hole is in the sidewall, the tire should be replaced because the sidewall cannot hold pressure reliably after a patch. If the tire has multiple punctures or visible damage, replacement is safer.

What is the difference between Presta and Schrader valves?

Presta valves are narrow and common on road and gravel bikes; Schrader valves are wider and common on mountain and casual bikes. They are not interchangeable — a Presta tube will not fit a Schrader rim hole and vice versa. Check your rim before buying a new tube, or bring your wheel to the shop and ask the staff to confirm which type you need.