Before you start: what you need
For most bikes you need a pump that fits your valve, ideally one with a built-in gauge, and a few seconds to check the tire afterwards. A floor pump is the easiest tool for regular use. A small hand pump is fine for the trail or the road, but it takes more effort and usually does not read pressure as accurately.
Identify your valve
Bike tires usually have one of two valve types.
- Schrader: wider, and the same style as a car tire valve. It has a small pin in the center and generally needs no preparation.
- Presta: slimmer, with a small nut at the tip. You unscrew the nut before pumping and tighten it afterwards. See our guide to pumping up a tire with a small (Presta) valve for the details.
Many pumps have a head that fits both. If yours does not, a small adapter can bridge the gap.
Find the right pressure
Look at the sidewall of the tire. Most tires print a pressure range, often in both psi and bar (or kPa). This is a guide from the manufacturer, and the upper figure is typically a limit, not a target. Never go above the maximum printed on the tire or on the rim, whichever is lower.
Within that range, the best number depends on several things:
- Tire width: wider tires are generally run at lower pressures than narrow ones.
- Rider and load weight: heavier riders and loads usually need more pressure.
- Surface and riding style: rougher ground and off-road riding tend to call for lower pressure, while smooth pavement allows more.
- Tubed or tubeless: tubeless setups can often run lower pressure, though the manufacturer’s range still applies.
If you are unsure, start in the middle of the printed range and adjust by small amounts over a few rides based on comfort, grip and handling. The bike tire pressure chart gives typical starting points by bike type.
Is 20, 40 or 90 psi right?
There is no single answer, because it depends on the tire. A wide mountain bike or fat bike tire may be run at pressures that would be far too low for a narrow road tire. A road tire may be run at much higher pressures than a mountain bike tire. The sensible check is whether the number sits inside the range printed on your own tire’s sidewall. A figure well below that range can risk pinch flats or rim damage, and a figure above the maximum risks the tire coming off the rim.
Step-by-step inflation
- Remove the valve cap and keep it somewhere safe.
- Prepare the valve. On a Presta valve, unscrew the small nut counterclockwise until it stops, and press the tip briefly to free it. Schrader valves need nothing here.
- Attach the pump head. Push it straight onto the valve as far as it goes, then flip or twist the lever to lock it, if your pump has one.
- Pump steadily. Watch the gauge if there is one. Use smooth strokes and keep the pump upright, so you do not bend the valve.
- Stop at your target pressure. If you overshoot, you can let a little air out (see how to safely deflate a bike tire).
- Release the head. Open the lever first, then pull the head off. A brief hiss is normal.
- Close the valve. Tighten the Presta nut gently with your fingers, and replace the cap.
Check the result
Squeeze the tire and look at it from the side. It should hold its shape and not bulge around the rim. Then spin the wheel and look for wobble in the tire seating. If you have no gauge on your pump, a separate small gauge is worth having, since squeezing is not a reliable way to judge pressure.
Choosing a pump
- Floor pump: best for home. It is stable, quick and usually has a gauge.
- Hand or mini pump: easy to carry, slower, and best kept for emergencies.
- CO2 inflator: very fast on the road, but each cartridge is single use. See our CO2 inflator guide.
- Electric mini pump: convenient, though battery life and maximum pressure vary by model.
How often should you check?
Tire pressure drops over time, even without a puncture, and lightweight inner tubes tend to lose air faster. Many riders check before every ride, and it is a quick habit to build. Temperature changes can also affect pressure slightly.
Other situations
- No pump available? See inflating a bike tire without a pump.
- Letting air out or struggling with a stuck valve? Read how to safely deflate a bike tire.
- Riding tubeless? See seating a tubeless tire with a hand pump and adding tubeless sealant.
Troubleshooting
- Air hisses out while pumping: the pump head may not be seated or locked properly. Remove it and try again.
- The tire will not hold air: there may be a puncture or a leaking valve. Inflate it, listen, and check again after a few hours.
- The tire keeps coming off the rim or looks uneven: deflate it and reseat it, checking that the tire bead sits evenly in the rim.
FAQ
What psi should I inflate my bike tires to? Use the range printed on the sidewall as your boundary and pick a point within it based on tire width, weight and surface.
Is 40 psi too much for a bike tire? It depends on the tire. It may be reasonable for some wide tires and below the range for many narrow ones. Check your tire’s printed range.
Can I overinflate a tire? Yes. Exceeding the stated maximum can risk the tire blowing off the rim, and very hard tires can feel harsh and give less grip.