??BCD?? What is this

Hi All,

Pardon my ignorance, this will be the first of many dumb questions i am sure to ask.

With regard to a crankset, what is the BCD? I am guessing it is the measurement of what size cog will fit the individual crankset.

Am i right?

I have sugino 175 cranks and when i measure across from one “arm” to the opposite side it is about 120-130mm, is this correct?

Sorry for the silly questions, i am just about to start rebuilding a “find” and want to make sure i am sourcing the right parts.




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