How to choose the correct bicycle size in 2024: Practical guide for cyclists

When buying a second -hand bike, one of the first doubts that arises is how to hit the adequate size. Does a m o l size come better? Or maybe a size 53 or 55? Quiet, you are not the only one who asks it! In 2024, with the innovations of brands and their different ways of indicating sizes, it may seem more complicated than ever. But here we help you understand it in a simple way.

Mountain or road bike? Understand the difference in sizes

First, it is important to know that the way a bicycle is measured varies depending on the type. For the mountain bicycles, carvings are usually indicated in inches. For example, a MTB of size 17.5 inches means that the vertical tube, which connects the pedalier with the armchair, measures that: 17.5 inches. Now, some manufacturers are also starting to use the centimeters, which adds some confusion.

On the other hand, the road bicycles They are traditionally measured in centimeters. So, when we talk about a size 54 on a road bike, we are referring to the vertical tube measuring 54 centimeters.

Realistic image of two bicycles in different environments. On the left, a road bike with aerodynamic box and thin tires on a paved road; On the right, a mountain bike with thick tires and flat handlebars, located on a ground path in a mountainous environment. The background combines urban and natural landscapes, highlighting the versatility of both types of bicycles

The change in frame geometries

Things have not always been so complicated. Until the 90s, bicycle sizes were quite universal. A size 54 of a brand like Orbea It was practically the same as a size 54 of Colnago. But this changed when Giant introduced the paintings with Sloping. This term refers to the angle of falling the horizontal tube, which altered the dimensions of the bicycle and how they were measured. Now, the fact that two bicycles have the same vertical tube does not mean that they are of the same size.

Today, each manufacturer uses its own angles and geometries of picture, which means that a person measuring 1.70 m may need a size 17 in a brand and size 19 in another.

System of letters in letters or numbers?

To add more complexity, some manufacturers prefer to use a cargo system based on letters: XS, S, M, L, XL ... while others remain in the system numeric: 50, 52, 54, etc. A true mess, we know it! But in Tuvalum We have collected information from more than 30 manufacturers To help you better understand how each system works.

Here are one equivalence table that can guide you:

Generic size	Size in centimeters	Inch size
Xs	46, 47, 48, 49	14"
S	50, 51, 52, 53	15", 16"
M	54, 55, 56	17", 18"
L	57, 58, 59	19", 20"
XL	60, 61	21", 22"
XXL	+62	+23"

How to calculate your size according to your height

Ok, you know that sizes can vary between brands and types of bicycles. But how can you know what your size is? Most manufacturers offer Height -based guides, although you must keep in mind that the height is not everything. Two people who measure the same can have leg lengths different, which will affect the size they need.

Therefore, we have prepared a Reference Table that will help you find the right size according to your height:

You measure	Road size (cm)	MTB size (inches)	Generic size
From 1.55 to 1.60	47 - 48 - 49	14 - 15	Xs
From 1.61 to 1.65	49 - 50 -51	15 - 16	S
1.66 to 1.70	51 - 52 - 53	16 - 17	S
From 1.71 to 1.75	53 - 54 - 55	17 - 18	M
From 1.76 to 1.80	55 - 56 - 57	18 - 19	M
From 1.81 to 1.85	57 - 58 - 59	19 - 20	L
From 1.86 to 1.90	59 - 60 - 61	20 - 21	L
+1,90	+61	+22	XL

The trick of measuring the length of your legs

To achieve even more precise size, the key is to measure the Internal length of your legs. Uncommutes, stand up with straight legs and measures the distance from the ground to your crotch. You can help you with a book to mark the height. Once you have this data, you can calculate your ideal size.

If it is one mountain bike, multiply the measure of your legs by 0,21. For example, if your length is 90 cm, the size would be approximately 19 inches.
For one road bike, multiply the length by 0,65. Thus, with 90 cm, you get a size of 58 cm.

This method is much more reliable than only based on height, although it is not infallible. The Geometries The paintings constantly change, so factors such as the length of the arms or your flexibility also come into play.

What happens if your size is between two measures?

If when calculating your size it turns out that you are between two measures, here are a couple of criteria to guide you:

Biomechanical criteria: Measure your size (the length of your arms from end to end). If it is greater than your height, choose the largest size. If it is less, opt for the smallest size.
Criteria for use: If you are looking for a bicycle to compete or make demanding routes, choose the smallest size. For more recreational or comfortable use, it is better to go for the biggest size.

Two bicycles of different side size, with a tape measure between them, representing the choice between two bicycle sizes.

Right with your bicycle size

Choose the correct bicycle size It may seem complicated at the beginning, but with adequate information and some simple measurements, you can make it much easier. In Tuvalum, we have worked to collect all the necessary data and offer you a Complete guide To find your ideal second -hand bike, without worrying about size.

And if you still have doubts, you can always get a Fitting o Biomechanical study to make sure you choose the perfect bike for you.