sisärenkaat

Sisärenkaat are a type of inner tube used in pneumatic tires, primarily for bicycles. They are essential components that hold the compressed air within the tire, allowing it to cushion the ride and maintain the tire's shape. The inner tube is typically made of a flexible material, often butyl rubber, which is airtight. It has a valve stem that protrudes through a hole in the outer tire and rim, allowing for inflation and deflation.

The purpose of a sisärengas is to provide a sealed, airtight chamber for the air pressure. When a tire is inflated, the air pushes outwards against the inner tube, which in turn pushes against the outer tire casing, giving it its firm and round shape. This air pressure is what absorbs shocks from the road surface, providing comfort and traction. Without the inner tube, the tire would not be able to hold air and would flatten, rendering the bicycle unrideable.

Common issues with sisärenkaat include punctures, which can be caused by sharp objects like thorns or glass. A punctured inner tube will lose air, leading to a flat tire. Repairing a puncture typically involves patching the hole with a rubber patch and adhesive, or replacing the entire inner tube. Over time, inner tubes can also develop leaks due to age or wear, necessitating replacement. The size and type of sisärengas must match the dimensions and intended use of the outer tire.