What is the difference between Presta valve and Schrader valve for inner tubes?

[StLucia]

Here are the differences between Presta valve and Schrader valve for inner tubes: 1. Locking mechanism differs: Presta valve uses manual locking, withstands high pressure, has smoother air leakage curve, features thinner valve base with smaller diameter (lighter weight), causes less impact on rim strength, can be used on 19C inner tubes or narrow rims, but is more expensive. Schrader valve mainly relies on internal pressure for sealing, also withstands high pressure but has steeper air leakage curve (leaks faster when pressure is low), has larger valve base and diameter, but provides greater inflation flow rate - thus widely used in larger-volume inner tubes for convenient inflation. 2. Different applications: Schrader valves are most common for mountain bikes. Sealing is achieved by higher internal pressure and spring pressure on the piston. During inflation, a small needle in the pump head pushes down the piston. Advantages include better air tightness and common availability; disadvantage is potential air leakage during severe bumps with limited length options. Presta valves are used on nearly all road bikes and some mountain bikes but are less common in daily life. The valve is thinner than Schrader. The piston is secured by a small nut, making it more reliable than Schrader. Inflation requires unscrewing the nut completely - the piston gets pressed down when connecting the pump. Advantages include higher reliability and availability of long valves for wide rims. Disadvantages are higher cost and inconvenience when using public pumps (most repair shops can't inflate them) - users without personal pumps should carry a Presta-to-Schrader adapter.