Do all derailleurs fit all bikes?

Do I need a specific derailleur?

Most road bike front derailleurs are compatible with traditional and compact chainring sizes but as with MTB mechs, you will need to choose a derailleur to suit the number of chainrings you are running as well as being mindful of mount type.

Do all rear derailleurs fit all bikes?

A derailleur for your mountain bike should match the specifications on the original derailleur. That is, while it doesn’t need to be the same model of derailleur, it does need to be the same brand, in almost every case. It also needs to match the number of gears, or have more intended.

Are rear derailleur hangers universal?

Depending on what manufacturer and year of the model you have, you may get a universal derailleur hanger if one of the original OEM ones isn’t available for your bike model.

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