Shimano BB-RS501 Hollowtech II Bottom Bracket | ITA 70 mm

Shimano BB-RS501 Hollowtech II Bottom Bracket | ITA 70 mm

Shimano BB-RS501 bottom bracket allows you to install a crankset with a 24 mm axle into a road bike frame with threaded bearings.

Shimano recommends using this bottom bracket with Tiagra, Sora, Claris, Alfine, and GRX RX600 series cranksets.

It features an optimized seal design that enhances durability. The bearing cups are made of steel, while the bearings are crafted from anodized aluminum. When combined with a compatible crankset, this bottom bracket, along with its Hollowtech II technology, ensures stability and efficiency with every pedal stroke.

ITA (Italian Threaded) is a bottom bracket version commonly used by Italian bicycle manufacturers. It is one of the two main types of bottom bracket threading, with the other being BSA (British) threading. The primary difference between ITA and BSA threading is their geometric layout.

Shimano's Hollowtech II technology represents an advanced crank and bearing system aimed at achieving the ideal balance of stiffness, weight, and rotational efficiency. The system integrates the bottom bracket with the right crank arm, using a 24 mm axle or bearing diameter, which is optimal for stability. High-quality bearing seals ensure a long service life for the component.