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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.

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