Gravel Tyre Pressure: Chart by Weight, Width & Terrain
On a gravel bike, tyre pressure affects comfort, grip and speed more than almost any component. A wide tyre with too much pressure does not absorb anything, and one with too little squirms and bottoms out. Here you will find starting values by rider weight and tyre width, and learn how terrain, rim and tubeless shift the number.
Tyre pressure chart for gravel bikes
The values apply to tubeless tyres, mixed terrain (tarmac, farm track, gravel), a 25 mm inner rim width and a bike of about 10 kg. “Rider” is body weight including clothing, backpack and bottles, without the bike. Pressure is given in bar, front / rear, with psi below.
| Rider | 32 mm | 35 mm | 38 mm | 40 mm | 45 mm | 50 mm |
|---|---|---|---|---|---|---|
| 60 kg | 2.7 / 3.039 / 43 psi | 2.3 / 2.533 / 37 psi | 2.0 / 2.229 / 32 psi | 1.8 / 2.026 / 29 psi | 1.5 / 1.621 / 23 psi | 1.3 / 1.319 / 19 psi |
| 70 kg | 3.0 / 3.444 / 49 psi | 2.6 / 2.938 / 42 psi | 2.2 / 2.532 / 36 psi | 2.0 / 2.230 / 33 psi | 1.6 / 1.824 / 26 psi | 1.4 / 1.520 / 22 psi |
| 80 kg | 3.4 / 3.749 / 54 psi | 2.9 / 3.242 / 46 psi | 2.5 / 2.736 / 40 psi | 2.3 / 2.533 / 36 psi | 1.8 / 2.027 / 29 psi | 1.5 / 1.722 / 24 psi |
| 90 kg | 3.7 / 4.154 / 60 psi | 3.2 / 3.546 / 51 psi | 2.7 / 3.040 / 44 psi | 2.5 / 2.836 / 40 psi | 2.0 / 2.229 / 32 psi | 1.7 / 1.824 / 27 psi |
| 100 kg | 4.1 / 4.559 / 65 psi | 3.5 / 3.850 / 55 psi | 3.0 / 3.343 / 48 psi | 2.7 / 3.039 / 43 psi | 2.2 / 2.432 / 35 psi | 1.8 / 2.026 / 29 psi |
Two things stand out: pressure falls steeply with tyre width, and the rear always needs a little more than the front. At 80 kg, a 35 mm tyre runs about 2.9 / 3.2 bar (46 psi), while a 45 mm tyre needs only 1.8 / 2.0 bar (29 psi). That is no coincidence: a wider tyre carries the same load with more air volume, so the pressure does not need to be as high.
What determines tyre pressure on a gravel bike
- Weight: What counts is the total of rider, kit and bike. About 57 percent of it sits on the rear wheel, which is why the rear tyre runs slightly higher. With bikepacking bags the weight rises, and the pressure should go up by 0.1 to 0.2 bar (2.9 psi).
- Tyre width: The wider the tyre, the less pressure. If you move from 38 to 45 mm, lower the pressure by roughly a quarter.
- Inner rim width: A wider rim supports the tyre, which becomes effectively wider and needs less pressure. As a rule of thumb the value changes by about 2 percent per millimetre of inner width. Modern gravel rims of 24 to 28 mm are one reason pressures are lower today than they used to be.
- Terrain: On hardpack gravel or tarmac a little more is fine; on loose gravel, sand or forest tracks, less.
- Casing: Thin, light casings tolerate and need less pressure than robust ones, but they are more prone to rim strikes.
Corrections for setup and terrain
The chart is the starting point. Use these factors to adapt it to your bike:
| Situation | Factor | Example (2.3 bar (33 psi)) |
|---|---|---|
| Tubeless (base) | × 1.00 | 2.3 bar (33 psi) |
| Tubeless with insert | × 0.95 | 2.2 bar (32 psi) |
| With inner tube | × 1.10 | 2.5 bar (36 psi) |
| Hardpack gravel / tarmac | × 1.05 | 2.4 bar (35 psi) |
| Loose surface | × 0.92 | 2.1 bar (30 psi) |
With a tube you need more pressure because a pinch flat between rim and obstacle destroys the tube instantly. Tubeless lets you run lower pressure, but if it is too low the tyre can leave the rim in corners (“burping”). How to convert to tubeless is covered in the guide Converting to tubeless.
Hookless rims
Many modern rims have no hook on the rim edge. They are lighter and easier to mount, but they come with a pressure limit: under ETRTO, hookless rims are generally limited to 5 bar (72 psi). The lower of the rim and tyre figures is binding. On gravel bikes this is rarely a problem, but it can be for heavy riders on narrow tyres. The chart above stays under the limit; it matters mostly with narrow tyres, high weight and road wheels with tubes. In the tyre pressure calculator you can select “hookless” and it limits the value automatically.
Fine-tuning on the trail
- Start with the chart value and correct it for setup and terrain.
- Too little pressure: the bike feels vague in corners, you feel the rim on impacts, or the tyre loses air (“burping”).
- Too much pressure: the bike skips over washboard, the tyre loses grip, and your hands and back tire sooner.
- Change in steps of 0.1 to 0.2 bar (2.9 psi) and ride the same route to compare. A precise gauge is worth it, because track pumps are often off by 0.2 bar (2.9 psi) or more.
- Write down the best value. In the digital garage My bike you can save setups.
Frequently asked questions about gravel tyre pressure
How many bar for a 40 mm gravel tyre?
For an 80 kg rider, tubeless and mixed terrain, about 2.3 bar (33 psi) front and 2.5 bar (36 psi) rear is a good starting point. With inner tubes add roughly 10 percent, with inserts subtract roughly 5 percent.
Why do gravel riders run lower pressure than they used to?
Wide tyres at low pressure conform to rough ground instead of bouncing the bike around. That adds grip and comfort, and on rough gravel the bike usually rolls no worse and often better.
How much pressure can a hookless rim take?
Hookless rims are usually limited to 5 bar (72 psi) under ETRTO. The rim and tyre manufacturers' figures always apply, and the lower of the two counts.
Calculate your gravel tyre pressure →