The new X.9 rear derailleur held up well (Image credit: James Huang)
Trickle-down technology is the boon for all performance-loving (but cash-strapped) cyclists out there, and few bits in recent memory have exemplified this trend more than the latest round of SRAM's X.9 MTB transmission.
The initial X.9 generation offered up competent capabilities, but it was hardly awe-inspiring. While it included most of the same features as the top-tier X.0 (including the outstanding 1:1 cable pull ratio and thumb-thumb trigger configuration), it just didn't feel as good in use and didn't quite offer up the same reassuring tactile feel as its big brother. X.0's characteristic 'Pop! Pop!' was translated into more of a muffled 'puff puff'… as if it were being suffocated with a pillow.
That gap narrowed to virtually nil for 2007 as SRAM gave X.9 a significant functional and visual overhaul. New rear derailleur features include a decidedly more X.0-like appearance that at least seems more rigid than before, a forged aluminum B-knuckle for improved durability (original cast aluminum ones were somewhat prone to failure), and a sealed bearing lower pulley.
