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What pressure should I run?
Anybody who gives you one pressure without asking what you weigh is guessing. Enter what is actually on the road and the tyre you actually run: this is the table from our tyre guide with the gaps filled in.
What is on the road
Total on the road: 87 kg
Start here, then adjust
Rear3.9 bar57 psi
Front3.5 bar51 psi
- 87 kg on a 38 mm tyre: 3.9 bar rear from the table, tubeless.
- Front: a tenth off the rear — about 60% of the weight sits over the back wheel.
If the bike pings over rough tarmac and your hands go numb, you are too hard. If the tyre squirms in corners or the rim strikes, you are too soft. Move in 0.2 bar steps, one end at a time, and always use the same gauge.
The number on the sidewall is a certified maximum, not a recommendation. If the tyre also states a minimum, never go below it on a tubeless setup.
Where the numbers come from
- The table is the one in our tyre guide: rear, tubeless, aiming for the casing to compress about 15% of its height under load.
- Between the table’s columns pressure is interpolated on a curve — it falls with width roughly as width to the power −1.4, which is what the table itself does. Along a column it is a straight line in weight.
- The adjustments are the guide’s, as numbers: front a tenth under rear; tubes +0.4 bar; smooth dry +0.2; wet or broken −0.25; a hookless rim capped at 5 bar.
- Outside 40–150 kg and 23–70 mm the table is being asked to guess, so inputs are held at those limits.
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