Product Description

S-PARTS Titanium B-Axle Bolt for Shimano Ultegra R6800 / RD-6800 Rear Derailleur

Upgrade your Shimano Ultegra R6800 / RD-6800 rear derailleur with a lightweight, precision-machined titanium B-axle bolt from S-PARTS. Designed as a replacement and weight-saving upgrade for the original hardware, this bolt combines high-strength Grade 5 Titanium (Ti-6Al-4V) construction with precision machining and multiple titanium finishes for a refined custom look.

Key Specifications

Lightweight Grade 5 Titanium

S-PARTS uses carefully selected Grade 5 Titanium (Ti-6Al-4V) from qualified high-performance metal suppliers, with material selection supported by long-term laboratory comparison and testing to meet S-PARTS quality standards.

With an average tensile strength exceeding 1,050 MPa, Grade 5 Titanium offers an excellent strength-to-weight ratio. Under comparable conditions, S-PARTS titanium fasteners provide mechanical performance comparable to 10.9-grade steel hardware, while weighing approximately half as much as comparable steel components.

At just 6.97 g per piece, this titanium B-axle bolt provides a significant weight-saving opportunity while maintaining the high-strength characteristics required for precision bicycle hardware.

Precision Forged and CNC Machined

The B-axle bolt is formed using a dedicated S-PARTS forging process to achieve consistent geometry and structural integrity. Each fastener is then precision-machined using advanced CNC equipment.

Strict dimensional and thread tolerance control ensures clean, precise threads and consistent fitment. Every detail is carefully machined to deliver the combination of precision, durability, and refined appearance expected from premium titanium hardware.

Multiple Titanium Finishes

Choose from a variety of finishes to match your bike and components.

Gold, Rainbow, Black, and Blue are produced using a PVD vacuum coating process, creating a dense surface coating that enhances surface hardness, wear resistance, and finish durability.

Green, Purple, and Candy are produced through electrolytic anodizing. This process forms a controlled titanium oxide layer on the surface. The resulting color is created by the interaction between light and the oxide layer rather than conventional paint or dye.

Natural Titanium retains the characteristic appearance of polished titanium, while Indigo offers another distinctive color option for custom builds.

Candy Color Variation

Due to the nature of the titanium coloring process, the Candy finish has a fluid and highly variable appearance. Color tones and transitions may vary from piece to piece.

This variation is a natural characteristic of the finishing process and is not considered a defect.

White Lines on the Threads

Some pieces may show white lines or light-colored marks on the threaded section.

This is a normal visual effect caused by the coloring process and does not affect the normal use or performance of the bolt. Please use the product with confidence.

IMPORTANT: The B-axle bolt must be installed together with the original factory sealing ring from the Shimano rear derailleur. Please retain and reuse the original sealing ring during installation.

Installation Note

Before installation, please confirm that the bolt specifications and derailleur model match your original hardware.

Use an appropriate 5 mm hex key and follow the manufacturer's recommended installation procedure and torque specifications. Do not overtighten the bolt.

This product is a replacement/upgrade fastener only and does not include the rear derailleur or other components.