2020 ETRTO standards for bike tires


Starting from January 2020, the size of bike tires will be subject to new rim widths standards. The nominal size of bike tires, similarly to the size of motor bicycles tires and car tires, is based on specific rim widths indicated by the ETRTO standards.

Learn more about ETRTO: https://www.etrto.org/home

As a matter of fact, the size (section) of a tire mounted on a rim is not universal, as it can slightly differ according to the width of the rim on which the tire is mounted. Current trends among users suggest an increased interest in wheels with larger rim widths. This pushed wheel producers and tire producers to consider larger rim widths for naming the size of a tire. This is where the new ETRTO standards are rooted.

The following table shows the new ETRTO standards that will be valid starting from January 2020 onwards:

Tire section (mm) Measuring rim width (mm)
18-21 15C
22-24 17C
25-28 19C
29-34 21C
35-46 23
47-57 25
58-65 30
66-71 35
72-83 45
84-113 76
114-132 94

Because of the application of the new standards, tires with the same nominal size but with different actual size will be available in the market simultaneously. In any case, the construction rim width is engraved on the Vittoria tires side wall for reference.