Riding a bicycle by yourself or with friends can be great entertainment and exercise. Part of owning a bike is taking responsibility for its upkeep and maintenance. After many miles of riding your bike, you might need to replace the wheel. Before you can buy a replacement, you'll need to do some measuring. To determine the correct bike wheel size, include the measurement for both the diameter of the wheel and the width of the tyre around the wheel.
Stand your bike up straight. You don't need to remove the wheel from your bike to measure it. Lean the bike against a wall so it's as straight as possible, or ask a friend to hold it steady for you.
Place your tape measure at the base of the tyre tread touching the ground. This is your starting point for the measurement.
Measure the wheel from the bottom of the tyre tread to the top of the tyre tread on the opposing side of the wheel. This will include the diameter of the wheel, as well as the width of the bike's tyre.
Take your measurement to a bicycle shop to get the right size replacement bike wheel.
If you just need the tyre size, you'll find this printed on the wall of the tyre.