Tubes because they can stretch will list a range of widths.
Bike tire sizes explained.
Check out the following for 20 year old bike tires sizes explained.
International organization for standardization.
If there is no speed rating the m will precede the metric size.
Bicycle tires come in a bewildering variety of sizes.
23c 25c and 28c their width in mm.
Nowadays bike tires are typically marked according to iso standard a system originally developed by etrto european tire and rim technical organization but older english and french tire size dimensions are still used as well use the data from the following tables to determine interchangeability and convert between iso etrto english.
Road bike tires generally come in three widths.
When it comes to choosing width there are two major factors at play.
27 5 x 1 9 2 3 for example.
While the first number the diameter of the tire is most important in identifying size there s a little more to how tires are measured with a more globally unified approach.
Because of the high pressure and desired low rolling resistance road tires come in narrow widths.
Some older road bikes still have the 27 inch size.
Bike tube sizing essentially mirrors bike tire sizing with one exception.
Metric tires are most commonly used and can work for sport bikes cruisers touring bikes and others.
To make matters worse in the early days of cycling every country that manufactured bicycles developed its own system of marking the sizes.
Thus you need to be sure any new bike tube has sizing that has a width range that aligns with the sizing on your bike tires.
After the speed rating there will be a b or r to indicate if it is belted or radial tire construction.
Common road bike widths in millimeters come in sizes ranging from 18 to 23 with a typical road bike tire at 700 x 23.