The Shimano Zee RD-M640 is a lightweight and stable 10-speed rear derailleur. Because of its wide transmission it’s perfect for freeriding and DH. It showcases a switch which enables heavier spring tension to reduce chain bounce.
Loose chains often cause chain slap or derailment from the front chain ring. The clutch system when set to the ON-position dampens the cage and consequent chain movement for a virtually silent and stable riding experience. In the OFF-position it eases the installation and removal of the rear wheel by relaxing the spring tension of the cage.
The low profile design is intended for more aggressive riding. The derailleur will not hit the chain stays. The super low profile design carries many benefits. It performs smoothly and silently under all conditions. The low profile design saves the rear derailleur from damage in narrow or tricky passages.
• 10 speed compatible only
• Material: Aluminium
• Weight: 270g
• Largest sprocket: 36 teeth
• Overall capacity: 25 teeth
• Smallest sprocket: 11 teeth