Glossary

A Dual Hex Chainring Bolt is a type of fastener specifically designed for securing bicycle chainrings to the crankset spider. The term “dual hex” refers to the fact that both sides of the bolt— the bolt head and the nut—have hexagonal sockets, allowing a hex key (Allen wrench) to be inserted into each side simultaneously. This design prevents the nut from spinning while the bolt is being tightened or loosened, making installation and removal much easier and more secure.

Typically made from steel, aluminum, or titanium, dual hex chainring bolts consist of two parts: the male bolt and the female nut. The male portion threads into the female side, clamping the chainring tightly against the crank arm. Because both sides are hex-shaped, the fastener offers better torque control and reduces the risk of stripping, which is common with single-sided chainring bolts that rely on friction or special tools to hold the nut in place.

These bolts are common in high-performance bicycles, particularly road and mountain bikes, where precise torque and reliability are critical. The dual hex design ensures a tighter, more stable connection, minimizing loosening or creaking during pedaling.