## Cyclecomputer Calibration Group E

#### If the model name is highlighted, clicking on it will take you to detailed setting instructions.

CatEye Solar (miles); Paramount Series 8, 10 (miles); Sachs Huret (miles); Sigma BC 400 (miles); BC 500 (miles), BC 401 (miles); BC 500 (miles); BC 600 (miles); BC 700 (miles); BC 800 (miles); BC 1100; BC 1200+ (miles); BC 1400 (miles); BC 1600 (miles); Vetta Cycle Computer (miles)

### Circumference in millimeters/1.6093

See explanation if you are measuring using a rollout test. This calibration number is different from the one for kilometers for most of these cyclocomputers..

700 X 44 |
1382 |

700 X 38 |
1355 |

700 X 35 |
1347 |

700 X 32 |
1339 |

700 X 28 |
1327 |

700 X 25 |
1308 |

700 X 23 |
1302 |

700 X 20 |
1296 |

27 X 1 3/8 |
1349 |

27 X 1 1/4 |
1343 |

27 X 1 1/8 |
1339 |

27 X 1 |
1333 |

26 X 2.125 |
1286 |

26 X 1.9 |
1276 |

26 X 1.5 |
1234 |

26 X 1.25 |
1213 |

26 X 1.0 (559 mm) |
1189 |

26 x 1 (650C) |
1213 |

Wide 700C Tubular |
1316 |

Narrow 700C Tubular |
1308 |

26 X 1 3/8 |
1288 |

24 |
1191 |

24 x 1 |
1089 |

20 X 1.75 (406) |
927 |

20 X 1 1/4 (451) |
1005 |

17 x 1 1/4 |
838 |

16 x 1 3/8 |
797 |

These computers don't adjust their internal math -- instead, you change the calibration number. A mile is 1.6093 kilometers, and the calibration number for miles is the tire circumference divided by 1.6093. You can measure the tire circumference with a rollout test, then do the division.

The manual for the Vetta Cycle computer gives the calibration number for miles as 3.9042 times the radius of the wheel. This is the same as the circumference divided by 1.6093.

If you would like to make a link or bookmark to this page, the URL is:

https://www.sheldonbrown.com/cyclecomp_e.html

Last Updated: by Harriet Fell