
Just as expected, the new Shadow rear derailleur option seen on the new Shimano Deore XT group will also grace the company's top-of-the-line XTR group as well. The same configuration benefits will apply, including an 11-13mm narrower profile for better protection in rocky environments, a more direct cable pull, and a higher tension main body spring for a firmer feel at the lever and snappier shift for users that so desire it.
XTR's version will be a considerably higher end item than Deore XT's, though, and will actually be the lightest derailleur in the line. The RD-M972SGS/M972GS derailleur (indicating both mid- and long cage models) will weigh just 180g/182g (respectively) and will include a first-for-Shimano full carbon fiber cage assembly which helps shed 22g from the standard slant parallelogram versions.
Retail pricing has not been announced yet, but the new rear derailleurs are scheduled to be available in September.