Bike tubes are an essential component when cycling. Inner tubes keep the tyre inflated, giving you a safe and comfortable ride. You can see what size your tube is on the tyre wall, as well as its correct inflation pressure. If you are unsure, always choose a slightly smaller bike tube for your tire, as using a large tube is likely to cause it to burst. There are two valve types, auto valves (also called Schrader) and french valves (Presta). French valves are more expensive and tend to be used in higher pressure or more sensitive environments, like racing.