Set your e-bike tire pressure, step by step

The tire maker prints a minimum and maximum pressure on the sidewall (Bosch, Canyon). Schwalbe says never to go above the maximum or below the minimum (Schwalbe). Lectric also points riders to the sidewall for its tires (Lectric).

Some rims have a lower limit than the tire. Schwalbe says the lower of the two always wins. For hookless rims, it notes a 5 bar limit for road use and says to follow the wheel maker's pressure specs (Schwalbe hookless, Schwalbe tubeless). Your bike's manual or the wheel maker lists the rim limit.

Bosch describes three valve types. Schrader is the car-style valve. Presta is slim and has a small nut at the tip that you loosen before pumping. Dunlop is larger and tapered (Bosch). Most floor pumps fit both Schrader and Presta.

There is no single right number. Schwalbe says the biggest factor is the load on the tire, mainly rider weight plus cargo. Narrower tires and heavier loads need more pressure, and wide tires can run lower (Schwalbe). As a rough guide, Bosch gives 3 to 4 bar for city and trekking bikes and 2 to 3 bar for mountain bikes (Bosch). Bosch also gives the conversion: 1 bar is 14.5 PSI.

• Smooth pavement: Canyon says higher pressure rolls better (Canyon).
• Dirt and rough ground: lower pressure absorbs bumps and grips better (Canyon).
• Comfort on the street: Lectric suggests a few PSI under the sidewall maximum, but warns that lower pressure raises the risk of pinch flats (Lectric).
• Tubeless tires can run slightly lower than tubes (Schwalbe).

Bosch and Schwalbe both say the thumb test doesn't work. A tire feels hard from about 2 bar, and you can't feel the difference between 3 and 4 bar (Bosch, Schwalbe). Use a floor pump with a gauge, or a digital gauge for more precision (Canyon).

Turn the wheel so the valve is at the bottom. On a Presta valve, loosen the tip first, then lock the pump head on (Bosch). Pump to your target, then check the reading again once the head is off if you use a separate gauge.

Set both tires, ride your usual route and adjust in small steps until the bike feels steady and comfortable. Canyon says too little pressure makes the steering feel spongy (Canyon). Stay inside the sidewall range.

Schwalbe says to check at least once a month, since losing about 1 bar a month is normal (Schwalbe). Heat also raises pressure, so Canyon suggests a check before long hot descents (Canyon). While you're there, Bosch suggests looking for cracks, brittle rubber and worn tread (Bosch).