Speed and distance data can be collected from either a speed sensor or GPS data. Within the sensor menu, you can choose a wheel size and set a preference to use GPS or speed sensor data to calculate speed and distance.
To collect accurate speed data from a speed sensor, you will need to set your wheel size within the sensor settings. To set your wheel size, go to: Main Menu > Activity Sensors > Select speed sensor > Wheel Size.
| Rim / Tire Size | Diameter (mm) | Circumference (mm) |
| 700 x 20mm | 662 | 2080 |
| 700 x 23mm | 668 | 2099 |
| 700 x 25mm | 672 | 2111 |
| 700 x 28mm | 678 | 2130 |
| 700 x 32mm | 686 | 2155 |
| 700 x 35mm | 692 | 2174 |
| 700 x 38mm | 698 | 2193 |
| 26 x 2.00 | 660.6 | 2075 |
| 26 x 2.30 | 675.84 | 2123 |
| 26 x 2.50 | 686 | 2155 |
| 26 x 4.00 | 762.2 | 2395 |
| 26 x 4.80 | 802.84 | 2522 |
| 27.5 x 2.00 | 731.6 | 2298 |
| 27.5 x 2.30 | 746.84 | 2346 |
| 27.5 x 2.50 | 757 | 2378 |
| 27.5 x 2.75 | 769.7 | 2418 |
| 27.5 x 3.00 | 782.4 | 2458 |
| 29 x 2.00 | 723.6 | 2273 |
| 29 x 2.30 | 738.84 | 2321 |
| 29 x 2.50 | 749 | 2353 |
| 29 x 2.75 | 761.7 | 2393 |
| 29 x 3.00 | 774.4 | 2433 |
To set your preference on whether to use GPS or the speed sensor for speed and distance, go to: Main Menu > Activity Sensors > Select speed sensor > Movement > GPS or Speed Sensor.
