Most MTB bicycle rims are "clincher" rims for use with clincher tires.
What is Clincher
A "clincher" is the most common type of rim used on bicycle wheels. Clincher bicycle rims are similar to automobile rims in terms of how the tire adheres by means of a ridge on the inside of the rim that "clinches" a bead running along the inside of the tire.
How a Clincher Works
A clincher bicycle wheel "clinches" the tire by means of a ridge on the inside of the wheel rim. When the tire is properly mounted on the rim, beads made from wire or other strong material along the inside of the tire seal snugly against the ridges inside the rim. When the tire is mounted on the wheel rim and properly inflated, it holds firmly in place without shifting or moving.
The Advantages of Clinchers
Clinchers are quicker to install, the tires are generally cheaper than tubular tires, and flats usually require only replacement of the inner tube and not the entire tire. They are consistent and reliable, also they huge range of widely available equipment options.
They're by far the easiest option to learn and live with, they're inexpensive to buy and repair.
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