How to know the correct pressure to swell the wheels of your bicycle?
We know that this is one of the most frequent doubts that we are regarding the maintenance of our bicycle, either from road, mountain, Grave either Electric. Bringing the proper pressure in the bicycle tires will improve the driving experience and its behavior. But, on many occasions, it may be difficult to find the proper measure. This is because there are a number of both mechanical and cyclist factors that cause inflation pressure not to be the same in all cases. Among that first group of factors, we must highlight the size of the wheel, the width or ball of the tire, the type of compound with which it is manufactured or the width of the tire. Likewise, aspects such as the cyclist's weight, its usual conduction style, the type of land or the weather conditions also influence the pressure to which the wheels of a bicycle should be infected: higher, lower ... we will explain How all these factors influence the choice of the ideal pressure of your tires. At the end of the post we will show you a complete table where you can find the recommended pressures considering all these variables.
Two references to measure the tire pressure: the PSI and the bar
Before analyzing each of the aspects that influence the pressure to which the bicycle wheels must be swelling, you have to start clarifying some measurement terms. Especially for those who still are confused when applying the correct pressure through a pressure gauge (pressure meter). In the swollen pumps with pressure gauge, the guides in PSI (pounds per square inch) and bar usually appear. Both are units to measure the pressure, the first is more used in Anglo -Saxon countries and the second most international. You can measure the pressure of your tires with any of the two references, although the PSI guide may be more convenient. This is because in bicycle tires, most manufacturers usually indicate the recommended pressure on PSI. However, and especially in Spain, the bar has imposed more among most cyclists. The equivalence between both units is that of 1 bar = 14.5 psi.
1 bar = 14.5 psi
In this way, it is important to have an inflation pump first, to be able to stand, with built -in pressure gauge. This will allow us to calibrate the pressure of each of the tires, discarding the imprecise method to the touch.
BAR/PSI equivalence table
| BAR | 0,5 | 1 | 1, | 2 | 2,5 | 3 | 3,5 | 4 | 4,5 | 5 |
| PSI | 7 | 15 | 22 | 19 | 36 | 44 | 51 | 58 | 65 | 73 |
| BAR | 5,5 | 6 | 6,5 | 7 | 7,5 | 8 | 8,5 | 9 | 9,5 | 10 |
| PSI | 80 | 87 | 94 | 102 | 109 | 116 | 123 | 131 | 138 | 145 |
Factors that influence wheel pressure
Here are some relevant factors that influence when determining the most appropriate pressure to which we must swell the wheels of our bicycle.
The tire size
The tire size, its diameter and wide or ball, largely determine the pressure it must have. In Mountain BikAnd, for example, possibly the modality where the pressure of the covers plays a more important role, a cover of 27.5 inches in diameter will have greater rolling resistance (the contact surface with the ground will be greater) than another of 29 ” That is why you will need to infly with more pressure. The same happens with a narrower tire. Taking the measures of the Mountain Bike And attending to the recommended pressures table of the manufacturers, the pressure, as a general rule, 0.2 bars per 0.2 inches that the ball is reduced. In road cycling the width of the tires is usually expressed in millimeters. The standard is usually that for every 1 mm that the width is reduced, the pressure must increase the pressure.
Thus, attending only to the width of the tire, we can obtain a pressure measure very close to our needs. Wider covers will always provide greater grip and stability with less pressure. But at the same time they will wear more quickly than narrower, which will not be as stable and manageable as the former, but more agile and fast. Related to this, the internal width of the tire also influences. Like the tire itself, a larger tire width requires less pressure than one narrower.
The tire material
Manufacturers offer different versions within each model of tires depending on the type of compound used. The resistance of each of them is measured in TPI (Threads per Inch - Threads per inch). A higher TPI, lighter and less resistant will be the compound of the one made. A tire with greater TPI will require a pressure increase. On the other hand, a minor one, that is, with fewer threads of the compound necessary for its manufacture, will be more resistant to wear and, therefore, will require less pressure to obtain its ideal performance. On the other hand, the chosen anti -punctures solution also influences the variation of the pressure. If wheels with tires TUBELESS, you can lower the pressure between 0.2 and 0.3 bars, obtaining the same or better performance, since you will reduce the moving weight of the wheels.
The wheel position (front or rear)
In addition, another mechanical factor to take into account is the position of the tire, if it is the striker or the rear. It is advisable, and this is recommended by the main manufacturers of the sector (Michelin, Maxxis, Schwalbe or Continental) that both wheels do not carry the same pressure, indicating a 60-40 cast for the rear tire and the striker, respectively. This is because the motor wheel, the rear, will need more pressure due to its greater rolling condition than the front. And the latter needs greater grip and stability because it is responsible, in the first place, to turn the bicycle, in addition to absorbing a good part of the impact of obstacles and irregularities of the terrain.
The cyclist's weight
The weight of the cyclist is one of the factors, together with the width of the tire, determinants when choosing the ideal pressure. A cyclist who weighs more will need to print more pressure to its covers than one more thin. The weight itself increases the tire rolling surface or band and, therefore, reduces speed and increases wear. Each manufacturer recommends a certain pressure according to weight stripes. But, in general, and as an initial reference point, for every 5 kg of weight more we will have to increase the pressure 0.1 bars.
The type of land and climate
The most specific tire pressure settings are determined by the type of terrain (smooth or irregular) and weather conditions. All of them are external aspects that can change from one day to another. That is why it is recommended that, based on a reference pressure taken into account by the factors described above, you varies more or less within margins depending on the land profile through which you are going to leave and/or the time you do. Thus, the more smooth and firm the terrain is, the greater the pressure will be beneficial. While irregular, rough firm, with obstacles or slippery (wet, with mud or sand) it is convenient to reduce it slightly to increase grip. On the other hand, although less important due to its small impact during the output itself, a lower external temperature reduces the tire pressure. The manufacturers disagree as it is reduced depending on the degrees, but approximately for every 10º C less the tire will lose 0.1 bar, because the air tends to contract with the cold.
Recommended pressures for bicycle tires
Taking into account the most important factors when choosing the correct tire pressure, which are the width or ball and the weight of the cyclist, we have prepared this table or general pressures. On this occasion, we divide it into the two most practiced modalities of cycling, MTB and road, taking into account the ranges recommended by the main manufacturers.
Wheel pressures for Mountain Bike
| Cyclist weight (in kg) | Tire width (in inches) | ||||
| 1,9" - 2,1" | 2,2" - 2,3" | 2,4" - 2,5" | 2,6 " - 3" (Plus) | 3.8 " - 4.5" (Fatbike) | |
| 60 kg | 2 bar / 29 psi | 1.9 bar / 27 psi | 1.7 bar / 24 psi | 1.2 bar / 1.7 psi | 0.5 bar / 7 psi |
| 70 kg | 2,1 bar / 30 psi | 2 bar / 29 psi | 1.8 bar / 26 psi | 1.3 bar / 1.9 psi | 0.6 bar / 9 psi |
| 80 kg | 2.2 bar / 32 psi | 2,1 bar / 30 psi | 1.9 bar / 27 psi | 1.4 bar / 20 psi | 0.7 bar / 10 psi |
| 90 kg | 2.3 bar / 33 psi | 2.2 bar / 32 psi | 2 bar / 29 psi | 1.6 bar / 23 psi | 0.9 bar / 13 psi |
| 100 kg | 2.4 bar / 35 psi | 2.3 bar / 33 psi | 2,1 bar / 30 psi | 1.7 bar / 24 psi | 1 bar / 14 psi |
Wheel pressures for road bike
| Cyclist weight (in kg) | Tire width (in millimeters) | ||||
| 23 mm | 25 mm | 28 mm | 30 mm | 32 mm | |
| 50 kg | 6 bar / 87 psi | 5 bar / 72 psi | 4 bar / 58 psi | 3 bar / 43 psi | 2.6 bar / 38 psi |
| 60 kg | 6.7 bar / 97 psi | 5.6 bar / 81 psi | 4.6 bar / 67 psi | 3.5 bar / 51 psi | 2.9 bar / 42 psi |
| 70 kg | 7.3 bar / 106 psi | 6.3 bar / 91 psi | 5.3 bar / 77 psi | 4.1 bar / 59 psi | 3.2 bar / 46 psi |
| 80 kg | 7.8 bar / 113 psi | 6.9 bar / 100 psi | 6 bar / 87 psi | 4.8 bar / 69 psi | 3.5 bar / 51 psi |
| 90 kg | 8.3 bar / 120 psi | 7.4 bar / 107 psi | 6.5 bar / 94 psi | 5.4 bar / 78 psi | 3.9 bar / 56 psi |
Finally, if you want to customize the pressure of your covers, a very useful and novel tool is to use a specific app. In the Google Play Store (for Android phones) or App Store (for iPhone) you can find several options, just searching through the term "covered pressure." We recommend using Bike Tire Pressure Calculator. In addition, the main websites of bicycle tire manufacturers have their own press calculators. Only by entering data such as the width of the tire, the type of compound or your weight you can immediately obtain the appropriate pressure for both the front and rear wheel. An example is practice Schwalbe press calculator For MTB.
