SRAM have confirmed details of the new 11-speed XX1 groupset, which is due to be in the shops by October 2012.
The X-Dome cassette offers a huge 10-42t gear ratio - that's the biggest spread available in the market on a single-ring setup, while keeping weight low at 260g. The single-unit cassette combines with an XD driver freehub body for what SRAM call "a superior connection to the wheel". Wheels equipped with the XD driver freehub will only initially be available from SRAM and DT Swiss.
The XX1 crank uses carbon arms and an aluminium spider, with six CNC-machined chainrings (28-30-32-34-36-38) available. Back in May we wondered whether the new chainring magnetic teeth to keep chain on but, as it turns out, this is not the case and a new super-deep tooth profile claims to reduce the need for a chain device - "maximum chain control" are SRAM's words. Claimed weight is 650g with BB.
SRAM's new X-Horizon rear derailleur, which is expected to weigh approximately 220g, uses a 'horizontal parallelogram' design - which SRAM call X-Actuation - and pulley offset to try and achieve a constant chain gap across all 11 gears, which SRAM say will provide fast, precise shifts.
Gripshift or trigger shifters will be available
And finally, for now at least, the dedicated 11-speed XX1 chain is designed "to deliver the greatest strength and reliability to a drivetrain that doesn’t have to make compromises for front shifts". .