SRAM is targeting mid-March for riders to get their chains around the new XG999 nine-speed mountain bike cassette.
The XG999 uses the same manufacturing techniques that produced the XX MTB cassette as well as the PowerDome road cassette. With the XG999 cassette, seven of the cogs are CNC-machined together out of a single block of billet steel, creating a lightweight, precise and strong cassette.
The entire manufacturing process for the XX, including machining, quality checks and finishing is said to take nine hours per cassette. With the XX ten-speed cassette, the weight savings is immediately noticeable due to the hollowed construction (the 11-36-tooth weighs just 208-grams and the 11-32-tooth is a featherweight 185-grams).
The nine-speed XG999 weighs in at 175 grams (11-32), and since it shares the same open design as the XX, it will allow mud to flow through, which aids in cleaner shifting and longer component life.