Sometimes, not using a tool is easier and faster than having to track it down. Besides, it's an added satisfaction to be able to perform a project with just your hands. In this instance, I will show the easy way to change a bicycle tire without using those pesky and break prone tire levers. This works very well for mountain bike tires or essentially wide tire. I've tried it with road bike tires, but they are tighter to the rim it's much more difficult to do.
I put this instructable together for my hackerspace, Bloominglabs, for the makerspace contest.
Step 1: Deflate Tire and Loosen Bead
Most likely you'll be able to skip this step as the tire is already flat. I mean, there aren't many other reasons to change a bike tire tube. But should you need to let some air out and you don't have a pressure gauge to properly deflate the tire, the top of the valve stem cover works well (or any other small and fairly pointed object).
When the tire is deflated, I find it helpful to squeeze the sides of the tire all around the tire to help break the tire loose from the rim. This is especially helpful if it's an older tire that has been on the rim for a long time.
Step 2: Pull Off One Side of the Tire
Here's the trick of the entire instructable. It takes some hand strength, but less than you'd think.
1. On one side of the tire, place your hands about 4 inches apart across the tire.
2. Push in and up with your thumbs.
3. Use your fingers to press the tire forward to bring the tire wall over the side of the rim.
4. Use one hand to keep the tire wall on the outside of the rim and use the other to perform the same in and up motion with the other hand where the tire wall is sitting on top of the rim. The tire will continue working itself off of the rim.
5. When you have a decent portion of the tire wall out, you can put your fingers inside the tire wall and slide it along the remaining portion of captive tire.
Step 3: Remove the Tube
Now that you have one side of the tire out, you can remove the tube.
1. Push the valve stem up threw the the rim and pull it out the side.
2. You can now start pulling out the remainder of the tube.
Step 4: Put in the New Tube
You have now either fixed the current tube or replaced it with a new one, so now you have to put it back into the tire.
1. Lay the tube over the side of the tire and get the valve stem lined up with the valve stem hole.
2. Squeeze the tire where the valve stem hole is located. Push the valve stem through the valve stem hole.
3. Pull on the valve stem to make sure that as much of the stem is through the hole as possible. You may have you work at it a little bit as it can stick.
4. If the tire doesn't come back over the tube by itself, lift it up and over.
5. Starting next to the valve stem, start pushing the rest of the tube into the tire. Take care not to twist the tube.
Step 5: Adjust Valve Stem
The last thing to check is whether your valve stem is straight. A small angle doesn't matter, but too much of an angle can damage the valve stem over time. The tire hasn't been inflated yet, so may as well fix it now. All you have to is hold several rim spokes with one hand and pull the tire so that the valve stem is straight with the other.
Step 6: Push the Tire Wall Back Inside the Rim
Now that you have the tube back inside the tire, it's time to push the tire wall back inside the rim.
1. Pretty much the reverse of removing the tube, squeeze the side of the tire and push it over the rim wall.
2. Use one hand to hold the starting point in place and use the other hand to continue working more of the tire inside the rim.
3. Once it holds itself, you can use both hands to work the remaining tire, which you'll need when you get to the end.