When Shifting Goes Wrong: A Snapped Derailleur Hanger on a Cannondale Synapse
The Job
A Cannondale Synapse 1 (aluminum frame, Shimano Tiagra 2×10) came into the workshop with a clear problem: the rear derailleur hanger had snapped clean through. The derailleur was hanging loose, and the bike wasn't going anywhere until it was replaced.
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