SIGMA BC 509 - Manual (Page 14)

5.2 Wheel size chart (Radgröße / Wheel size / Circonference de Roue)
mm x 3,14 km/h:
WS = mm x 3,14
mph:
WS = mm x 3,14
1x
= WS (mm)
km/h:
WS = mm
mph:
WS = mm
A
B
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