The Shimano Tiagra BB-RS501 bottom bracket is designed for use with Hollowtech II cranksets and standard threaded BSA frames. It fits 68mm and 70mm shell widths, making it compatible with a wide range of road bikes.

Improved Sealing for Longevity: Engineered with Shimano’s new seal construction, this bottom bracket is built to reduce water and dirt ingress. The enhanced sealing helps maintain smooth rotation over time, minimizing wear and increasing durability.

Optimized for Performance and Efficiency: The BB-RS501 offers a stiff and stable platform for the crankset, enabling efficient power transfer with every pedal stroke. It ensures a secure fit and optimal bearing alignment to reduce energy loss.

Trusted Hollowtech II Design: Shimano’s Hollowtech II system integrates the bottom bracket and crank arm to provide a lightweight and high-performance interface. This bottom bracket delivers on that promise with easy installation and low maintenance.

Whether you're upgrading or replacing a worn-out part, the BB-RS501 is a dependable choice for road cyclists looking for value, reliability and smooth operation in all conditions.