How To Measure a Tire
Please follow these three steps to measure your tire.
-
Measure the outside tire diameter
To get the tire size, measure the outside diameter of the tire. Sometimes, the overall tire size is written along the sidewall of your tire. Though this won’t provide you with information regarding your hub length and bearing size (those are separate measurements), it will help determine which tire size you need. Measuring the tire diameter of the tire will help to confirm that information.
-
Measure the hub length
 
The hub length is the measurement through the middle of the wheel (or hub) measuring from end point to end point (or bearing to bearing). You’ll want to make sure to measure through the center of the wheel and not just the outside as there will be space in your rim that will go unaccounted for. You’re trying to determine how much “space” the rim takes up on your axle. If you order a hub length that is too short, the tire will move from side to side on your axle. If you order a hub length that is too long, your rim will extend beyond your axle.
-
Measure the bearing size
The bearing is the metal piece on the end of your hub where your axle goes through. You just need to measure the inside diameter of the hole. To double check accuracy, you can also measure your axle diameter as well to be sure you have the correct size.
Tire Definitions
|
| Tire: |
Tire portion only |
| Wheel: |
Tire and Rim together |
| Hub: |
Center tube that holds bearings |
| Bearings: |
Where the axle rests |
Click here to see expanded view
|