BMC Derailleur Hanger

This specific hanger is designated as Dropout No. 70. Because BMC produces many frame variations, you should verify the model number stamped on your existing hanger or consult your bike's technical manual to ensure compatibility before purchasing.

The hanger acts as a sacrificial link between your derailleur and the frame. By bending or breaking during an impact, it absorbs the force that would otherwise damage your bike's frame, which is significantly more expensive to repair or replace.

While some minor bends can be corrected with a hanger alignment tool, the metal often weakens after being bent and straightened. For the most reliable shifting performance and to prevent future failure, replacing a damaged hanger is always the safer, more precise option.

Installation is straightforward and typically requires only a set of hex keys to remove the old hanger and secure the new one. However, once installed, you should always check your derailleur indexing and limit screws to ensure the alignment is perfectly dialed in.

Yes, it is highly recommended. Derailleur hangers are specific to frame models and can be difficult to source quickly; keeping a spare in your gear bag or toolbox ensures you aren't sidelined for days or weeks if you have a mishap on the trail or road.