Q-tubes are great reliable replacement tubes that come in a variety of sizes for most applications from the smallest kids bike to world class race bikes.
- Presta valve tube have an external thread and are thinner that standard Schrader valve tubes. An adaptor can be fitted onto this
external thread to permit the Presta valve to be connected to a pump
with a Schrader head.
- If you are going to use Presta tubes in a rim that is designed for Schrader tubes you must use an adapter such as the Wheels Manufacturing Presta Saver to prevent damage to the valve stem.
- Presta tubes work better in high pressure tires because the valve has no return spring which pushes the valve closed under pressure. You close the valve by turning the valve core shut.