7-8-9-speed rear derailleurs

The rear derailleur is the component of a bicycle's drivetrain that is responsible for moving the chain between the various cogs on the rear cassette.
The number of speeds of the derailleur is determined by the number of toothed pinions on the cassette. Depending on this, a compatible derailleur must be selected.
When choosing the right 7,8 or 9-speed derailleur, there are several factors to consider, to ensure compatibility and optimal performance.

Cage length: Shifters are available with short, medium and long cages. The length of the cage is mainly determined by the gear range of the cassette.
Make and model: When selecting, stick to reputable brands that are known for producing reliable components. See reviews and recommendations for specific models. Popular brands include Shimano, SRAM, microSHIFT and Campagnolo.
Mounting type: There are various mounting options, including direct mounting and frame hanger mounting. Make sure it matches your bike frame.
Weight: Consider the weight of the derailleur, especially if you're dropping grams off the weight of the bike. But keep in mind that other factors, such as durability and functionality, are also crucial.

By considering these factors, you'll be better prepared to choose a rear derailleur that fits your bike, riding style and preferences. Don't forget that proper installation and compatibility are key.

Check out our video How to replace the rear derailleur?