Derailleur
Desviador
- Date
- 1949 · confidence medium
- Place
- Vicenza, Italy
- Credited to
- Tullio Campagnolo
- Field
- Movement
⚠️ Disputed: the sources disagree.
What it is
Mechanism that shifts a bicycle chain between sprockets or chainrings to change gear; Tullio Campagnolo's parallelogram design, the 1949 "Gran Sport", became the basis of modern derailleurs.
Rudimentary derailleurs already existed in France from the early 20th century (e.g. Cyclo); Campagnolo's parallelogram design (1949) is the one that became standard on modern bicycles.
What it led to
- Indexed gear-shifting systems for bicycles
- Multi-speed road and mountain bicycles
- Precision components for competitive cycling