This unique adapter clamp has a slot to allow a braze-one front derailleur to slide a total of 10mm to fit cranksets with chainlines a particular derailleur may not been originally designed to work with.
Example: If you have an old road front derailleur, but want to run it with a crankset that has a wider chainline
If you want to use the Fiddler as just a regular front derailleur clamp without any special adaptation, just set your front derailleur to most inboard part of the slot.

Forged and CNC'd aluminum construction
For braze-on front derailleurs only
Only available for 28.6mm seat tubes at this time (most steel road, CX and gravel bikes)
10mm of adjustment
Anodized silver


Note of caution: This product is recommended for experienced mechanics who know what a properly set up front derailleur looks like and functions like and also know what chainline set-ups are improper, and can cause shifting problems or premature wear. This adapter doesn't change the cable pull of the front derailleur. Reckless experimentation with this product can result in an unsafe bicycle. Thoroughly test a new set up on the workstand before riding.