1-1/8 inch (31.8 mm) to 1-1/4 inch (34.9 mm) front derailleur shim

The Wheels Manufacturing Front Derailleur Shim (31.8 mm to 34.9 mm) is a precision-machined adapter designed to allow a front derailleur sized for a 31.8 mm seat tube to be mounted on bikes with a 34.9 mm seat tube. This robust shim provides a secure, slip-free fit while maintaining proper derailleur alignment for smooth, reliable shifting.

Made from high-quality material and finished for durability, it’s ideal for custom builds, drivetrain upgrades, or when swapping components between frames with different tube diameters.

Features:

• CNC-machined shim for front derailleur fitment adaptation
• Converts 31.8 mm derailleur clamp to 34.9 mm seat tube
• Ensures correct alignment and secure mounting
• Durable construction for long-lasting performance
• Perfect for builds, swaps and upgrades