How do I get the right tyre pressure for my bike?

 

Using the right tyre pressure on your bike or e-bike makes all the difference. Wearing the right pressure reduces the risk of punctures and makes for a more comfortable, precise and faster ride.

 

THE BASICS

First of all, you need to know the two units of measurement used to measure tyre pressure; PSI (pounds per square inch) and bar. In Spain, the bar is more commonly used, but most manufacturers indicate the pressure with PSI. 1 bar = 14.5 PSI. 

In general, the tyre pressure should be 10% of the rider's weight plus the weight of the bike. And you must know the absolute upper limit, which is the maximum pressure that must not be exceeded for safety, written on the sidewall of the tyre.

Higher tyre pressure means lower rolling resistance and better protection against punctures. Lower tyre pressure, on the other hand, offers more grip and comfort, as the tyre absorbs more shocks. On this basis, and bearing in mind that there is no optimum tyre pressure for all tyres, the influencing factors are:

 

 

 

Weight of rider and bike

The weight of the bike, rider and luggage is one of the main factors to be taken into account, as the inflation pressure depends on the load exerted on the tyre.

The heavier the tyre, the more pressure it requires. Generally, for each additional kilogram that the tyre supports, the pressure must be increased by 1%. As a percentage, not 1PSI.

In addition, the weight is often not evenly divided between the rims, so it is recommended to use different pressures. 60% of the rider's weight is carried by the rear wheel, so a higher pressure can be carried on the rear wheel. This way, the front wheel will have more grip and stability, which is ideal as it is the one that makes the bike turn and absorbs most of the impact of the irregularities of the terrain.

 

 

 

Surface to be ridden on, road conditions

The right pressure, taking into account the surface, is the one that allows the tyre to absorb road vibrations, so the tyre will be faster and the ride more comfortable.

If the pressure is too low, the bike will feel heavy when pedalling. And if you can feel every imperfection in the road, the pressure will be too high.

On good pavement, tyres will feel good at 100PSI, but if it is uneven, you will ride faster at 90PSI. The smoother and firmer the terrain, the higher the pressure will be beneficial. If riding on wet or muddy roads, it should be a little lower, to reduce the risk of slipping in corners.

In addition, the temperature must be taken into account: every 10°C less, the tyre will lose 0.1 bar, as the air contracts with the cold.

 

The size of the wheels

Another factor to consider is the size, diameter and width of the wheels. 

By looking at the tyre width and adjusting the pressure to it, you can achieve a pressure measurement very close to the ideal. Generally speaking, for every millimetre that the tyre width is reduced, the pressure should be increased by 0.5 bar.

The wider the tyre, the less pressure it needs. Narrow road bike tyres need high pressure to ride on the road without punctures, while wider tyres such as those on mountain bikes or fat bikes require less pressure.

 

Type of bicycle

Lastly, we are going to talk about the pressure that bikes need according to their type:

• Tyre pressure for MTB

Since not all mountain bikes are mountain bikes are not all the same, the pressure also depends on the use you make of it. If you use your MTB in town and for weekend rides in the woods, 3 bar is a good starting point. You will have good rolling resistance on asphalt and before a ride in the forest you can release some air for better traction.

On the other hand, if you use tubeless MTB tyres, your tyres can ride with less pressure, as you are less likely to get a puncture. And if you ride on demanding terrain, you should keep the pressure as low as possible, but high enough to protect your rims and tyres. 

• Tyre pressure for road bicycles

In general, for 25mm road bike wheels, 7 bar is sufficient pressure. But, as mentioned above, there is no one-size-fits-all standard, so this can be a good starting point for modifying it according to the other factors discussed above.

And remember, it is important to check your tyre pressure regularly, as tyres naturally lose air. The amount of air they lose will depend on whether they have small punctures, material wear or the fit between rim and tyre. The higher the tyre pressure, the faster the air loss.

 

You know, knowing the right pressure for your bike's tyres at all times and in all circumstances will allow you to improve performance and gain comfort and confidence.