There is no single right number for bike tire pressure. A road racer, a mountain biker and a commuter on a city bike need very different pressures, and even two riders on the same bike may not agree. The good news: with a few rules you can find your number in one or two rides.
Start with the range on the tire
Every tire has a pressure range printed on the sidewall, for example "50–85 PSI". Treat it as a limit, not a target: never go above the maximum or below the minimum. Your ideal pressure sits somewhere inside, and for most riders it is lower than the maximum.
Also check your rim. Many newer road and gravel wheels have hookless rims, which are limited to 72.5 PSI (5 bar), even if the tire says more.
Bike tire pressure chart
Starting points for a rider of about 160 lb (73 kg) with inner tubes. Go higher if you are heavier or carry luggage, lower if you are lighter or run tubeless tires.
| Bike type | Tire width | Starting pressure |
|---|---|---|
| Road bike | 25–28 mm | 70–90 PSI |
| Road bike, wide tires | 30–32 mm | 55–75 PSI |
| Gravel bike | 38–45 mm | 30–45 PSI |
| Hybrid / city bike | 35–45 mm | 45–70 PSI |
| Mountain bike | 2.2–2.6 in | 20–30 PSI |
| Fat bike | 3.8–5 in | 5–15 PSI |
What changes your ideal pressure
Rider weight
The tire carries you, so weight matters most. A heavier rider needs more air to avoid pinch flats and rim hits, a lighter rider can go lower and get more grip and comfort.
Tire width
Wider tires hold more air, so they need less pressure for the same support. That is why a 32 mm road tire feels fine at a pressure that would be far too soft for a 25 mm one.
Front and rear
Most of your weight sits over the back wheel. Run the rear tire a few PSI higher than the front. Mountain bikers often use a 2–3 PSI difference, road riders 5–10.
Surface and weather
Rough roads, gravel, roots and wet conditions all reward a bit less pressure. The tire follows the ground instead of bouncing over it. On smooth tarmac you can add a few PSI.
Tubes or tubeless
Tubeless tires can't pinch a tube against the rim, so you can usually run them a few PSI lower than tires with inner tubes. That gives better grip and fewer flats.
Signs your pressure is wrong
- Too high: the bike feels harsh and skittish, bounces over bumps and loses grip in corners.
- Too low: the tire squirms in turns, steering feels slow, the rim hits rocks or curbs, and you get "snakebite" flats with two small holes side by side.
Change the pressure in small steps of 2–5 PSI and ride the same loop to feel the difference.
Presta vs Schrader valves
Before you can add air, you need to know which valve you have.
- Schrader is the same valve as on a car tire: wide, with a small pin in the middle. Most kids' bikes, cheaper city bikes and many mountain bikes use it. Any gas station air hose fits.
- Presta is thin with a small lock nut on top. You find it on most road, gravel and better mountain bikes. Unscrew the nut a few turns and tap it once before pumping, and close it again afterwards. To use a car air hose you need a small brass Presta-to-Schrader adapter, which costs a dollar or two and fits on the valve.
Can you use a gas station air pump on a bike?
Yes, with a little care. Gas station pumps move a lot of air fast, and a bike tire holds very little. Add air in one-second bursts and check with a gauge after each one, or the tire can go from soft to bursting in seconds. If the machine lets you set a target pressure, set it first.
Find a free pump on the free air map, and keep a Presta adapter on your keyring if your bike needs one.
How often to check
Bike tires lose air faster than car tires because they hold so little. Check road bike tires before every ride, especially with latex tubes, which can lose noticeable pressure overnight. For other bikes, once a week is a good habit. A floor pump with a gauge at home makes it a 30-second job.