Bottom Brackets

Compared to the power transfer of the conventional square taper spindle, the 8-splined OCTALINK interface that connects the bottom bracket and crankset increases the strength and rigidity for the entire assembly.

Shimano BB-ES300 Octalink V2 Bottom Brackets - Fits Shimano Octalink V2 Spline Cranksets - Crankarm fixing bolts not included

Shimano BB-ES51 Octalink V2 Bottom Brackets - Fits Shimano Octalink V2 Spline Cranksets - Crankarm fixing bolts not included

BB-UN26 cartridge bottom bracket. - Smooth rotation - Square taper spindle - Sealed cartridge bearing assembly

Shimano's Dura-Ace Bottom Bracket Cups are perfect for Shimano's Dura-Ace Crankset. They feature durable composite construction, super-smooth sealed bearings, a plastic sleeve for additional protection, and they come in English and Italian threading.

Shimano's BB-UN55 Square Spindle Bottom Brackets are the unofficial standard for English-threaded cartridge bottom brackets. Quality, value, and durability come together to keep you cranking for many, many miles. - Fits JIS Square-Taper Cranksets - Hollow spindle - Crankarm fixing bolts not included

Shimano's Ultegra bottom bracket uses Pro Tour-proven technology for lighter weight and super smooth spinning, while still maintaining the same level of durability and stiffness. It's available in English, Italian, or Press Fit models.

Shimano Dura-Ace BB92, BB9000 Hollowtech II Bottom Brackets - Bottom Bracket Shell I.D.: 1.37" - Defined Color: Black - Weight: 65 g - Spindle Interface Type: Shimano Hollowtech II