Shimano BB-ES300 Acera Octalink Bottom Bracket (68-118mm)

Shimano BB-ES300 Octalink bottom bracket - for MTB and Touring

The Shimano BB-ES300 Octalink bottom bracket with 8-speed gears fits MTB and touring cranks installed in BSA bottom brackets with 68 or 73 mm shell width. Compared to its predecessor the BB-ES25, it can save up to 25 grams of weight. This is the standard version, which is not compatible with E-Type or chain cases.

Compatibility:
Octalink crank arms with eight-speed splines for longer grooves (Octalink MTB)

Key Features

• Compatibility: Octalink MTB crank arms with 8-speed splines

• Weight Reduction: 26g lighter than BB-ES25

• Construction: Hollow and reinforced for stiffness and durability

• Installation: Fast and precise

• Chainline Control: Maintains proper chain positioning for smooth shifting

• Application: MTB and touring bikes

• Material: Lightweight steel and composite components

• Performance: Efficient power transfer

• Durability: Reinforced ribs resist wear and stress

Product Specifications

• Type: Octalink bottom bracket

• Model: BB-ES300

• Shell Width Compatibility: 68-73 mm

• Gear Compatibility: 8-speed

• Weight: Approximately 26g lighter than predecessor BB-ES25

• Material: Hollow steel with reinforced ribs

• Crank Compatibility: Octalink MTB cranks

• Installation: BSA threaded bottom bracket shell

• Version: Standard (not compatible with E-Type or chain cases)

Build Quality

The Shimano BB-ES300 emphasizes both strength and weight efficiency. Its hollow construction reduces weight while reinforced ribs enhance stiffness, providing durable performance under heavy loads. The Octalink design ensures superior crank-to-bottom bracket rigidity, supporting consistent pedaling power and long-lasting drivetrain performance.

Why Choose This Product

• Lightweight yet strong, improving pedaling efficiency

• Compatible with a wide range of 8-speed MTB and touring cranks

• Precise chainline control for smoother gear changes

• Fast and reliable installation

• Proven Shimano Octalink system for rigidity and durability

In the Box

Shimano BB-ES300 bottom bracket

Installation hardware

Instructions manual