VDO Cyclecomputing C4 Instruction Manual page 32

GB
If applicable, enter wheel size 2 as described above
If you don't need to enter the second wheel size, hold the b key until the computer returns to
main menu TRIPDISTANCE/SETTINGS.
Watch out: Default settings for the wheel sizes are as follows: Bike 1 = 2155 mm and Bike 2 =
2000 mm. In case you don't set your individual wheel sizes, the computer works with default
values. Readings for speed therefore are likely to deviate significantly from the actual values.
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