Want a fun way to change the character of your bike? Change the tires. A set of smooth tires on your mountain bike, for example, will give a much faster ride on pavement. Tires also wear out, of course, and learning to replace them will save you money. Because tires come in many sizes, take your old tire with you when purchasing a replacement, to make sure you get the size right.
Removing the old tire
Remove the wheel from the bike. Most bikes now have a quick-release lever on each axle. Simply flip one of the levers to loosen the wheel. Once loose, the wheel can be pulled free.
Older bikes usually have two axle nuts holding each wheel in place. Use an adjustable wrench to loosen one of the nuts, thus allowing the wheel to come free.
Completely deflate the tire.
Slide the rounded end of one of the tire tools between the tire and the rim. Working slowly and taking care not to pinch the tube, pry the tire away from the rim by locking the free end of the tire tool into the spokes.
Slide a second tire tool between the tire and rim. Work this tool around the rim until the tire pops free (see A).
If the tool gets stuck, lock the free end into the spokes and begin working with the third tire tool.
Remove the tire and inner tube from the rim.
Installing the new tire
Take a new tire and slip one edge of it all the way around the rim. It should be possible to do this by hand, although you can use one of the tire tools if necessary.
Place the inner tube completely inside the new tire, taking care to line up the inner tube valve with the valve hole in the rim (see B). Push the tube as far into the tire as possible. It might help to inflate the tube very slightly.
Using your hands, push as much of the second edge of the tire onto the rim as possible. Continue pushing the tube into the tire as needed.
Insert a tire tool between the rim and the portion of the tire that is not yet installed.
Slowly lever the tool upward and force the tire over the rim edge. Use a second tool to push the tube into place if necessary.
Gently roll the tire into place over the rim edge. Work slowly and avoid snapping the tire into place as this tends to pinch the tube and cause air leaks.
Inflate the tire to the recommended pressure written on the side of the tire, and replace the wheel on the bike.