Weight:approx. 270 gram
Largest Sprocket: 36T
Smallest Sprocket : 11T
Compatibility: For 10 Speed Shifter Only
low cost, works great, reliable
Shimano introduces Zee, a new line of gravity components that are an ideal starting point for aggressive riders and racers. Zee is the gateway gravity component line that allows riders to get on board with Shimano’s gravity program and experience premium new component technologies at a price they can afford.
Shimano ZEE RD-M640 SSW Shadow is a lightweight and stable 10-speed rear derailleur. Because of its wide transmission its perfect for Freeriding. It features a switch which enables heavier spring tension to reduce chain bounce.
Chain bouncing can often cause noise as the chain slaps the top and bottom of the chain stay, or even derail from the front chain ring in extreme circumstances. The switch when set to the ON-position dampens the cage and consequent chain movement for a nearly 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 contact the chain stays, thus it's super quiet. 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.