How to measure bike tire size [5 Steps]

Bike tire size is one thing that most casual riders ignore. They forget that bike tires may never come in equal sizes, shapes, or type. Customers come with various tastes and sizes to cater for everyone’s needs. That is why you need to learn how to choose the ideal bike tire sizes for your riding comfort. When it comes to its performance, wheels matter, which is why having the right wheel size is a crucial factor. Here are some easy steps on how to measure bike tire size.

Step 1

Lean the bike on the wall on an upright position

You can use a kick-stand or lean it on the wall. Once the bike is upright, it will be easier to measure the wheels without shaking or tripping over. You may use a rectangle metallic tape measure if you are alone since it’s sturdier than a plastic one.     

Step 2

Measuring the wheel’s diameter

Hold the tape measure at the center of the bicycle wheel and extend it to the outer part of the tire. If you own an ancient bike, you must double the inches to get the diameter.  

Step 3

Measuring the bike wheel’s width

To get the width, pick a tape measure and line it on the ground, running across the tire’s thread on a straight line. The width varies depending on how you wish to use the tire. If you wish to use the bike on rough terrains, you need a bike with a wider width while those riding on smooth terrains will get a smooth and faster ride with a narrow width.  

Step 4

Measurements combination

After getting the width and the diameter, you can now combine the measurements to get the right tire size. If measuring the tire size for a traditional bike, start with the diameter and then the width. Standard bike wheels come with full-inch increments to determine the diameter. If the inches are a bit lower or higher, you can go to the nearest inch.

Measuring the bike wheel with ISO method

Step 1

Check the ISO measurement

To begin with, you need to check if your bike has the ISO system. However, it’s good to know that ISO uses millimeters instead of centimeters to signify the bike wheel size. If you lack a measuring tape that incorporates metric rules, note that you will get 25.4 in an inch. You can determine the diameter by multiplying the number on inches by 25.4. 

Step 2

Support the bike against the wall

Make sure the bike is properly supported against the wall or use the kickstand. After that, measure from the center to the inner side of the tire, but make sure they are in milliliters. Here, double the figure to get the diameter. Most adult bikes measure 650 to 700 Milliliters when it comes to the diameter according to the ISO measurements.  

Step 4

Measuring the width in milliliters

Use the above process to take the measurements across the thread from one end to the other. Note that tires with varying width can remain compatible with bikes with the same wheels. 

Step 5

List the width and the diameter

It’s good to remember that you need to list the width first and then the diameter when buying a tire with ISO measurement. 

Measuring the bike wheel’s size is not as challenging as you may have thought. Provided you follow the above steps, you will accurately measure the wheels on your bike successfully.