The Shimano Deore XT RD-M772 Shadow rear derailleur is the biggest and boldest innovation in the new XT line. It takes from some old and established design cues to create a derailleur that shifts crisply yet presents a minimal profile for crashing. A paradigm shift for the derailleur? ... read more

Shimano, though they say that their objective with the M770 redesign of Deore XT was to increase durability, they also did some serious dieting for their rear derailleurs. The Shimano Deore XT RD-M771 Top Normal Rear Derailleur is 26g lighter this year, and is supposed to be more durable... read more

Smoother, lighter, prettier. The new 2008 Shimano Deore XT RD-M770 Low Normal rear derailleur is taking its design cues from XTR, with a slightly bulkier X as the outer cage plate. After debuting a re-designed XTR this past fall, XT is doing what it always does, slowly closing the gap... read more

The SRAM Black Box ceramic derailleur pulleys are made of the same material as the standard pulleys, but they use polished stainless steel races and ceramic ball bearings in a sealed unit. The pulleys are a bit lighter and more durable thanks to the ceramic balls, but more importantly... read more

The culmination of 20 years spent creating and refining, X.0 is the pinnacle of the SRAM derailleur line. Every gram possible was shaved. The finish matches the look of the X.0 shifters. Forged alloy plates and links, save the Grilon P-knuckle. Machined and heat-treated oversized link... read more

Shimano is entering a new world with the RD-M972 XTR Shadow Rear Derailleur. Not only does this share the paradigm-shifting design of the XT Shadow rear derailleur with the amazing blingy good looks of previous XTR bits, but it is the first time Shimano has introduced carbon fiber to... read more

Shimano has picked up the gauntlet thrown down by SRAM when they released their X.0 line. There were plenty of “oohs” and “aahs” when X.0 came out and the upstart threatened to knock Shimano down a notch. Shimano waited to respond. They didn’t rush out a copycat design. They wanted to show... read more

Shimano demonstrates their ability to re-imagine components with their redesign of the XTR rear derailleur. The minimalist design outer X plate both works functionally as a lighter (less metal) and stronger (wider cage twists less), better shifting derailleur, but aesthetically as a branded part... read more

In terms of popularity, both here on the staff and our customers, SRAM is the rear derailleur of choice. Functionally the same as the X.O, the SRAM X-9 Rear Derailleur uses more aluminum and features serviceable pulleys. In terms of durability, this one should stand up to more use... read more

An armored car among derailleurs, this Shimano Saint rear derailleur is compatible with the Saint 135x10 rear hub (FH-M801), which it attaches to via the axle. It’s a top normal design, which works most easily with RapidFire Plus shifters.

Since it is a Saint, we ought to... read more