If you ride your bike long enough, you will eventually have to take care of a flat tire. Punctures are caused by a leak or puncture in the inflatable rubber chamber that is located between the wheel rim and the tread. Replacing a bicycle tube is an essential skill for any rider, whether they need to fix a puncture or just want to switch to a different one. Fortunately, it is also easy to do once you get the hang of it!
Steps
Part 1 of 4: Remove the wheel from the bike
Step 1. Lay the bike on its side to work on it
If you have access to a bike rack that will keep it upright, use it. If not, lay the bike on its side, but make sure the side with the chain and rear derailleurs is facing up. Turning the bike upside down (on the saddle and handlebars) is also fine if you are only removing the front wheel.
Step 2. Loosen the nuts that hold the wheel axle to the bike
You don't need to remove the lug nuts completely, just loosen them enough that the wheel can come loose (a few steps later). If the nuts won't budge when you use a wrench, apply lubricant like silicone spray or even cooking spray. If you have a modern bike with quick-release wheel locks, removing the wheel will be even easier; just open the zipper without removing the wheel for now.
Step 3. Disengage the brakes if they interfere with wheel removal
Different types of brakes have different release mechanisms, so check the instruction manual, or the website of the bike or brake manufacturer. In many cases, you will simply have to open a quick release located either on the brake calipers or on the brake handle on the handlebars. On the other hand, you may need to squeeze the calipers together to disconnect the brake cable from the calipers.
Step 4. Remove the chain from the gear discs if you are removing the rear wheel
Shift the gears so that the chain is on the outermost gear on the rear wheel and the innermost gear on the pedal axle. This will give the chain more slack to work. Pull back on the rear derailleur (the mechanism that guides the chain into position when a shift is applied) so that the chain comes off the teeth of the sprocket discs.
You can apply a patch to the tube of the punctured bike without removing the wheel completely, although this makes the patching job difficult; however, you have to remove the wheel completely to replace the tube
Step 5. Remove the wheel from the bike frame
For the front wheel, you simply have to direct the wheel axle (now that the nuts or quick release mechanism are loose) out of the fork that holds it attached to the bike frame. Do the same for the rear wheel, but in this case you need to steer the wheel downward and forward more carefully (if the bike is upright) past the chain and other obstructions. Keep pulling back on the rear derailleurs to help move the chain to one side.
Part 2 of 4: Remove the old camera
Step 1. Deflate the tire completely while it is still on the wheel you removed
For a Schrader (US) type valve, use a small tool (such as a thin Allen wrench) to press the plunger into the threaded cylinder. For a Presta type valve, unscrew the top of the stem to release the air. With a Dunlop-type valve, loosen the cap a few turns and then pull on the valve tip.
- Schrader valves are the same type as those in car tires. Presta valves are thinner and longer than Schrader valves, and have a locking nut at the tip. Dunlop valves are thinner than Schrader and thicker than Prestas, and are threaded only near the top.
- If the wheel has a locking ring that threads onto the valve stem to keep it attached to the bike rim, remove it after deflating the tube, but don't lose it!
Step 2. Remove a section of the outer wheel cover with two single levers
A pair of spoon handles or flat-head screwdrivers can serve as levers, but they should be inserted and used carefully when prying to avoid scratching or bending the wheel frame. Insert a lever between the outer tire and the wheel rim, and remove a section of the tire. Instead of seating in a channel on the inside of the rim, the tire should be on the outside of the rim at that point. Leave this cover lever in place.
To reduce the risk of damage to the wheel frame, purchase an inexpensive set of bike tire levers to do this job. You can get them at any bike shop or online
Step 3. Remove the rest of the wheel rim cover
Insert the other bucket, screwdriver, or tire lever into the gap between the rim and tire created by the first lever (which should still be in place). Slide this second lever around the entire rim and this way the outer tire should pop out of the channel as if you were unzipping your jacket.
Step 4. Remove the tube from between the outer cover and the wheel rim
Access the inside of the opening that you have created with the levers and grab the rubber chamber that is inside. Continue around the wheel and pull the camera out completely. When you get to the valve stem, push it in through the rim and out along with the tube.
Part 3 of 4: Install the New Camera
Step 1. Pump air into the chamber to be replaced until it has a basic circular shape
If you add too much air to the tube, it will be more difficult to reinstall. If you add too little, the outer cover is more likely to abuse the camera (and eventually puncture it) when you are reinstalling it.
If you are replacing the old tube due to a puncture, check for sharp objects on the inside of the outer shell. Use a flashlight to do a visual inspection, or wipe a thick cloth around the entire interior. Carefully remove anything you find. Do this before proceeding with the installation of the new tube, or you can end up with another flat tire
Step 2. Insert the new tube between the outer cover and the wheel rim
Start at the valve stem by inserting it through the hole in the rim. If the valve stem has a locking ring, hand tighten it to secure the stem in place. Then, methodically push the new tube into the gap all the way around the wheel. Take your time to make sure the camera isn't crooked or sticking out anywhere.
Step 3. Replace the cover over the inner rim of the wheel frame
Once the new tube is in place, use your hands to push one section of the tire at a time into the channel on the inside of the wheel rim. Pull on the cover with one hand while pushing with the other if necessary.
Step 4. Inflate the new tube with air to the recommended tire pressure
Look on the outer tire for the recommended pressure in psi (pounds per square inch), bars, or kilopascals. Use a pressure gauge to check the pressure to which you have inflated the tire.
An improperly inflated tire is more prone to a flat
Part 4 of 4: Reinstall the wheel
Step 1. Follow the same procedure used to remove the wheel, only in reverse
If you can remove a bicycle wheel successfully, you can fit it just as easily.
Step 2. Aim the wheel toward the fork on the bike frame
This is very simple for the front wheel. If you are fitting the rear wheel, pull the rear derailleurs to free the chain from the gear discs. Then, as you continue pulling the rear derailleurs, carefully guide the wheel into place.
Step 3. Reengage the brakes
Lock the latch on the brake calipers or on the brake handle if your brakes have a quick-release mechanism. Otherwise, squeeze the brake calipers together and feed the brake cable into place. Check the manufacturer's instruction manual or website for a specific manual for your brand.
Step 4. Tighten the lug nuts to secure the wheel in place
Use a wrench to make sure the nuts are tight and secure. However, do not try to tighten them so much that the nuts will "round", or they will be difficult to remove in the future.
- If your bike has a quick release mechanism for the wheels, simply close the latch to secure your wheel.
- Now you are ready to go riding!