Tires are one of the most essential parts of our bicycle, they are responsible for keeping us glued to the ground, cushioning us from small imperfections in the road, providing comfort and ride quality.
The tires are the only points of support of the bicycle with the ground, for that same reason, so to speak, they are your feet while you are on the bike, therefore it is necessary to choose a tire that fits perfectly to your needs, urban use, mtb, road, mixed, cargo-bike..
We will now explain each size in detail and its equivalence.
There are three ways to measure tires.
-English system (inches)
In the image we can see that we have the following indications:
35-584 (650x35B - 26x11/2)
-The indication 35-584 refers to the ETRTO (European Tyre and Rim Tecnical Organisation).
-The 650x35B indication refers to the French measuring system.
-The indication 26x11/2 refers to the inch measuring system.
We will focus on the ETRTO system as it is much simpler.
First the width is expressed, which can vary from 20 to 60, usually a two-digit number (AA). On special occasions the width can be greater or smaller. Then the rim diameter or inner diameter of the tire is expressed, which is usually a three-digit number (DDD), such as 559 or 622. The standard expression would be as follows:
An example would be: 37-622 where 37 is the width of the tire and 622 is the inside diameter of the tire (in this case 622mm)
Advantages of ETRTO
-Measurement in millimeters, therefore the measurement is very precise.
-Very simple measuring system, only two very differentiated measurements.
-The measurement of the inside diameter of the tire is the same as the diameter of the rim.
which tire should you choose?
For a good advice it is necessary to know what use you are going to give to the bike, and what is the environment where you usually move.
Classic bike tires are tires designed primarily for an urban environment (asphalt), but they are strong enough to ride on cobblestone roads, dirt roads ... as long as they are not mountain-bike roads
This measurement is the distance between the two walls of the rim. It must be taken into account that the rim width is not greater than the wheel width we have chosen, i.e. if we have a 30mm wide rim we cannot mount a 28mm tire, we need to mount a 30mm or larger tire (always speaking in ETRTO system measures)
Sporadic use of unpaved land
For this type of use we recommend a ball of between 28 and 32mm (ETRTO), because taking into account that our main environment is going to be paved terrain we need the minimum ball to offer the least friction possible, but enough so that we do not puncture when we get into unpaved terrain.
Mixed or freight use
If we are going to be this type of user, we will not care whether we ride on a dirt road or on the best paved city, therefore we will need a tire with a ball between 32 and 40mm (ETRTO) with the lowest possible friction. This type of tire is also recommended for bicycles that are overloaded or even equipped with a child seat.
Strictly urban use
This environment is probably the most favorable to avoid punctures, because riding on a paved surface also ensures a good ride quality and few bumps. For this type of use we recommend a 23 to 25 mm ball (ETRTO) because the narrower the ball is, the less friction it will offer and the less difficult it will be to pedal.
The wheel clearance is the distance between the rear chainstays or the width of the fork. The width of the tire or balloon cannot be greater than the distance between the rear chainstays on both sides, otherwise the tire would be trapped and the wheel would not be able to turn. Conclusion, the tire can not be wider than the wheel pitch, for example if I have a bicycle with a wheel pitch of 31mm I could not mount a tire of 31mm or more, because the wheel would be braked. I would have to mount a tire with a maximum of 30mm of balloon.
Keep in mind that the wheel pitch decreases as soon as fenders are mounted.
Tire tread pattern
The tire tread can also vary according to the environment and the user's needs.
Slick: Strictly urban use and in cities with little rain, it offers very good dry grip and little friction.
Semi-slick or light tread: Urban or semi-urban use, for rainy cities, dusty or sporadic use of unpaved roads. Provides good grip on paved terrain (wet or dry), and decent grip on unpaved terrain.
Tire with tread: This type of tire is the most versatile, it adapts to all the conditions of your environment, and offers good grip in all conditions suitable for a classic bike.