BCD GUIDE


USAMade BCD Guide
Measurement Between Bolt Circle
# of Bolt Adjacent Holes Diameter
Holes (Millimeter) (Inches) ( BCD )
4 45.3 1.78 64 mm
4 66.5 2.62 94 mm
4 73.6 2.90 104 mm
5 34.3 1.35 58 mm
5 43.5 1.71 74 mm
5 64.7 2.55 110 mm
5 76.4 3.01 130 mm
NOTE:  This applies ONLY when the bolt holes are evenly spaced around the circle. 
The newer 4-Bolt Shimano cranks have non-uniform spacing.  Select our Shimano style chainrings.