In the previous example a tube labeled 26 x 1 9 2 125 has the correct diameter of 26 inches.
Bike inner tube sizes explained.
This is the reason why you see inner tubes listed with one number for the diameter and a range for the width e g.
Because inner tubes stretch they typically come in a range of widths.
26 x 1 95 2 125 indicating that the tube is intended to fit a 26 inch tyre with a width of between 1 95 inches and 2 125 inches.
All inner tubes will come with a recommended range for tyre width for example 700 20 25 for traditional road tyres 700 25 32 for wider road tyres.
For example one of our most popular tubes is the 26 x 1 75 2 125 which means it fits a 26 inch diameter tire with a width in the range of 1 75 to 2 125 inches.
Then within these categories there are further sub divisions such as 26 inch 27 5 inch and the 29ers commonly.
700 or 26 but the tube s width will vary depending on the amount you inflate them like a kid s balloon.
A narrower inner tube will balloon.
Inner tubes vary in size depending on the circumference of the wheel and the width of the tyre.
27 5 x 1 9 2 3 for example.
Inner tubes typically state a wheel diameter and width range for which they will work e g.
Tubes because they can stretch will list a range of widths.
So a 29 inch mtb tube will have the same diameter as a 700c road wheel while a 27 5 inch tube will be the same diameter as a 650b road wheel.
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.
How to get the right bike tube and valve size.
The diameter needs to be the same e g.
Mountain bike tyre sizes are usually stated in inches.
Depending on whether your bike is a road bike touring bike mountain bike or child s bike the diameter and circumference of the wheel can vary.
