Let all remaining air out of the bicycle's tire.
First, try removing the bicycle's tire without the use of tools. Set the bicycle wheel on the floor with the valve at the three o'clock or nine o'clock position. Grab the top of the tire in one hand, and try to pull it sideways, over the top of the rim. With fat tire bicycles this is generally quite easy. With thin tire bicycles, you may find it nearly impossible.
If you cannot remove the tire without tools, use a couple of tire levers if you have them, or the backs of some forks or spoons. Try to avoid using sharp screwdrivers. Start by inserting one tire lever anywhere between the tire and the edge of the rim. Insert the lever just far enough to pry the edge of the tire over the edge of the rim.
It is very easy to poke a hole into the bicycles inner tube.
After prying the edge of the tire over, insert one more tire lever about four inches (10 cm) from the first one and pry a little more tire over the edge of the rim. Take out this second lever and re-insert it another four inches away and pry over the edge of the tire again here. Soon the whole side of the tire will be loose enough to finish prying over by hand.
Pull the inner tube out of the way and finish by prying the other side of the tire off the rim.
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