Bike Tyres and Pressure: Finding the Right Number
By Trailbound Editors · Published · Photo: Wikimedia Commons
Table of Contents
Quick Verdict
Most riders run too much pressure. The number moulded into the sidewall is a maximum for the tyre, not a recommendation for you. Start lower than you think, then raise it until the bike stops feeling vague in corners and stops pinching on the worst surface you ride.
Tyre pressure is the cheapest performance adjustment on any bike, and the one most riders never experiment with. It changes grip, comfort, and rolling resistance more than most components do.
The sidewall number is a limit
The pressure printed on the tyre is a maximum for that casing. It exists because the manufacturer has to state something, not because it suits your weight or your roads. Riding at the maximum on a rough surface costs you grip and comfort for no gain.
What pressure actually does
Lower pressure lets the tyre deform around small bumps rather than bouncing over them, which is why it grips better on gravel and feels more comfortable. Too low, and the tyre squirms in corners, the rim bottoms out on square-edged hits, and you get pinch flats.
Higher pressure rolls faster on smooth tarmac and feels more precise. Too high, and the bike skips across rough surfaces and wears you out.
The useful range is narrower than most people assume, and it sits lower than most people run.
Finding your number
- Check the tyre’s rated range and start in the middle.
- Ride a loop you know, with a rough section and a corner you trust.
- Drop pressure in small steps, two rides apart, and note how it feels.
- Stop when cornering feels vague, or the rim hits on a hard edge. Go back up one step and stay there.
Record it, front and rear separately. Most riders end up with a few psi less in the front than the rear, because the front carries less weight but does the steering.
Width and tread
Wider tyres let you run lower pressure without the rim hitting, which is why gravel and touring bikes have moved steadily wider. Tread matters less than people expect on the road, and more on loose or wet surfaces — but a knobbly tyre at the wrong pressure is worse than a smooth one at the right pressure.
Routine checks
Check pressure before a long ride rather than once a month, since tyres lose air over time and a slow leak is easy to miss. Replace tyres when the casing shows through the tread or the sidewall is cut, and replace the rim tape if you keep getting punctures on the inside of the tube.
Frequently Asked Questions
What pressure should I run?
It depends on your weight, tyre width, and surface. A practical method: start around the middle of the tyre's rated range, drop in small steps, and stop when cornering feels vague or the rim bottoms out on rough ground. Then go back up one step.
Wider tyres or higher pressure?
Wider tyres at lower pressure usually give more grip and more comfort for the same rolling resistance on rough surfaces. Higher pressure on a narrow tyre mostly gives a harsher ride and less contact with the ground.
Do tubeless setups change this?
They let you run lower pressure without pinch flats, which is the main practical benefit. They also need sealant maintained, and a puncture that will not seal is messier to fix at the roadside.
