130 BCD

The 130BCD crankset is a traditional road bike crank standard where the chainring bolts form a circle exactly 130mm in diameter. Commonly referred to as a “standard” road double. It has a 5-arm spider and was the industry staple for decades. Now there are other options like the compact 110mm and asymmetric 4-bolt setups.

Uses a 5-bolt, symmetrical circle pattern. If you are checking a chainring, the distance from the center of one bolt to the center of an adjacent bolt is roughly 76.4  mm. This calculates to a 130 mm BCD.