+ what types of valves are there?
Bikes typically comes with three types of valves around the world; Schrader valves, Presta, or Dunlop.
+ What’s the difference among the valves?
schrader valve—wider than Presta and the same circumference top to bottom. Often wrapped in rubber when used on wheels. The pin in the center is a spring-loaded check valve that controls airflow in and out, which requires pressure on the inner pin to let air in. Presta—about half as wide as schrader valve and made entirely of metal. It seals entirely based on pressure in the tube or tire. Dunlop—it looks like a fatter Presta and often found on city bikes.
+ What’s benefit using Presta?
They are lighter and requires a smaller hole in the rim, which improve performance in wheels. They seal tightly on air pressure alone. They are ideal for deeper-section aerodynamic rims when using with extension adaptors.
+ Will I ever need to replace a valve?
Normally you may need to replace a valve in two scenarios. When you have tubeless-ready wheels, Presta uses a knurled nut to seal the valve to the rim. If the seal is failing and start to lose air, it may be the time to replace the valve. When the Presta has replaceable cores, you can simply purchase a replacement core.