How to Fill a Presta Valve Bicycle Tire
- 1). Unscrew and remove the black plastic cap from the tip of the Presta valve. Unthread the nut until it's all the way out. The nut is not removed.
- 2). If the pump head is too big for the Presta valve, thread a Presta valve adaptor onto the valve until it's fully seated.
- 3). Fit the pump head onto the valve and lock the head in place.
- 4). Check the recommended tire pressure on the sidewall of the tire. The pressure will be listed in pounds-per-square inch, or PSI.
- 5). Inflate the tire to the recommended tire pressure. Unlock and remove the pump head from the Presta valve.
- 6). Thread the nut all the way down onto the valve. Replace the black plastic cap.
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