A Derivation of the Bolt Circle Diameter (BCD) Formula

As you may be aware if you’ve found this guide, a bolt circle is an imaginary circle that passes through the centre of the bolt or screw holes in a round pattern. This is typically a wheel hub on a vehicle, chainring on a bicycle or flange on a pipe. The diameter of this circle is known as the bolt circle diameter (BCD) or pitch circle diameter (PCD). Typically BCD is quoted for bash guards covering the chainrings on bikes and you can calculate it by measuring the distance between the fixing holes of the chainring. If you need to order a part for a bicycle, or check the BCD of a flange and can only measure the bolt hole spacing, you need to know the formula for working it out. <a href="https://medium.com/math-simplified/a-derivation-of-the-bolt-circle-diameter-bcd-formula-e2de402970aa">Visit Now</a>