follow these three steps to measure your tire.
1) 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
2) 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.
3) 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.