Sram presents new generation of rear derailleurs

The first pictures made the rounds back in January 2012, and now Sram is officially raising the curtain on a new product generation for shifting on the rear wheel: With the "Type 2" gear changers, a tensioning mechanism on the cage of the X0 and X9 groupsets ensures smooth gear shifting when rodeoing downhill. When designing the new rear derailleur, Sram also thought about easy installation and removal of the rear wheel.

Shimano got the ball rolling in 2011. With "Shadow Plus", the Japanese company had developed a tensioning mechanism for the XTR rear derailleur that keeps the chain in check even when shifting roughly. Now Sram is following suit with a similar technology, which is used on the gear changers of the X0 and X9 groupsets.

Slightly tense
In the so-called Type 2 derailleurs, a "roller bearing clutch" technology ensures that the chain is tensioned strongly to the rear by the shift arm. This tensioning mechanism at the height of the upper derailleur pulley is mounted on needle bearings, is self-lubricating and is designed to ensure a good and precise shifting feel, even with increased chain tension. This increased chain tension is permanently set and cannot be switched on and off using a switch, as is the case with Shimano's "Shadow Plus".

The new chain tensioning technology adds a modest 30 grams to the weight of the rear derailleur, with the X0 derailleur weighing 235 grams in size medium and the X9 derailleur weighing 250 grams in size medium. Both rear derailleurs are available in Large, Medium and Small lengths and are designed for 10-speed cassettes with a largest sprocket of 36 teeth. The X0 model comes in silver, black and red, while the more affordable X9 model comes in grey and white.

Simple wheel removal
However, Sram does not stop with a tensioning mechanism. At the same time as the chain tensioner, the Chicago-based component manufacturer is launching another mechanism on the rear derailleur to make removing and installing the rear wheel easier. Using "Cage Lock" technology, the shifting arm can be locked in a forward position, which greatly relaxes the chain. Once engaged, the rear derailleur swings backwards and makes room for the rear wheel and the cassette mounted on it to be pulled downwards out of the rear triangle. After installing the rear wheel, simply press the "Cage Lock" button to make the rear derailleur ready for use again.

According to the manufacturer, the rear derailleurs will go into production in July 2012 and are expected to be available in stores for the very first time in August.

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