Mountain Rear Derailleurs On Sale

SRAM X01 EAGLE Rear Derailleur - 52T Max
$179.00
SAVE 16 %
MSRP $214.00
Award Winner
*Free Shipping on $50+
Shimano XT RD-M8000 11SP Rear Derailleur
From $64.00
SAVE 40 %
MSRP $106.99
Award Winner
*Free Shipping on $50+
Swatch Image
SRAM XX1 EAGLE Rear Derailleur - 52T Max
$255.00
SAVE 21 %
MSRP $323.00
*Free Shipping on $50+
Shimano XTR RD-M9000 11SP Derailleur
From $179.99
SAVE 26 %
MSRP $243.99
Award Winner
*Free Shipping on $50+
Swatch Image
SRAM XX1 Eagle AXS Rear Derailleur - 52T Max
$675.00
SAVE 10 %
MSRP $753.00
Award Winner
*Free Shipping on $50+
*Free Shipping on $50+
Swatch Image
SRAM GX EAGLE Rear Derailleur - 52T Max
$119.00
SAVE 12 %
MSRP $135.00
Award Winner
*Free Shipping on $50+
Swatch Image
SRAM X1 Type 2.1 11SP Rear Derailleur
$139.00
SAVE 38 %
MSRP $224.00
Award Winner
*Free Shipping on $50+
Swatch Image
Shimano Saint RD-M820 10SP Derailleur
$132.99
SAVE 26 %
MSRP $178.99
Award Winner
*Free Shipping on $50+
SRAM GX 1X11 Speed Rear Derailleur
$115.00
SAVE 7 %
MSRP $123.00
Award Winner
*Free Shipping on $50+
SRAM X01 EAGLE AXS Rear Derailleur - 52T Max
$479.00
SAVE 11 %
MSRP $538.00
Award Winner
*Free Shipping on $50+
Shimano XT RD-M786 10 Speed Rear Derailleur
From $79.99
SAVE 23 %
MSRP $103.99
Award Winner
*Free Shipping on $50+
SRAM GX Type 2.1 10 SPD Rear Derailleur
$55.00
SAVE 23 %
MSRP $71.00
Award Winner
*Free Shipping on $50+
Swatch Image
Shimano Zee RD-M640 10SP Rear Derailleur
$55.49
SAVE 25 %
MSRP $73.99
Award Winner
*Free Shipping on $50+
microSHIFT ADVENT Rear Derailleur 9 Speed
$58.99
SAVE 9 %
MSRP $64.99
Award Winner
*Free Shipping on $50+
Swatch Image
Shimano Acera RD-M360 7/8 Speed Rear Derailleur
$23.99
SAVE 27 %
MSRP $32.99
Award Winner
*Free Shipping on $50+
Swatch Image
SRAM NX Eagle 12-Speed Rear Derailleur
$89.00
SAVE 23 %
MSRP $115.00
Award Winner
*Free Shipping on $50+
Swatch Image
Shimano SLX RD-M7000 11S Rear Derailleur
$55.00
SAVE 29 %
MSRP $76.99
Award Winner
*Free Shipping on $50+
Swatch Image
SRAM XX1 Type 2.1 11SP Rear Derailleur
$255.00
SAVE 21 %
MSRP $321.00
Award Winner
*Free Shipping on $50+
Swatch Image
SRAM X.4 7/8 Speed Rear Derailleur
$25.60
SAVE 20 %
MSRP $32.00
Award Winner
*Free Shipping on $50+
Swatch Image
Microshift Advent Rear Deraileur 9 Speed Long Cage
$30.56
SAVE 36 %
MSRP $47.99
Award Winner
*Free Shipping on $50+
*Free Shipping on $50+
Swatch Image
Shimano Altus RD-M310 7/8 Speed Rear Derailleur
$21.99
SAVE 21 %
MSRP $27.99
Award Winner
*Free Shipping on $50+
SRAM X5 Rear Derailleur
$45.00
SAVE 15 %
MSRP $53.00
Award Winner
*Free Shipping on $50+
Swatch Image
SRAM X.3 7 Speed Rear Derailleur
$19.20
SAVE 20 %
MSRP $24.00
*Free Shipping on $50+
Swatch Image
Shimano XT Di2 RD-M8050 Rear Derailleur
$267.99
SAVE 21 %
MSRP $339.00
Award Winner
*Free Shipping on $50+
Swatch Image
microSHIFT MarvoLT M46 Rear Derailleur
$23.99
SAVE 8 %
MSRP $25.99
*Free Shipping on $50+
Swatch Image
Microshift Advent Rear Deraileur 9 Speed Med No Clutch
$30.56
SAVE 36 %
MSRP $47.99
Award Winner
*Free Shipping on $50+
Swatch Image
microSHIFT XLE Rear Derailleur
$38.99
SAVE 9 %
MSRP $42.99
Award Winner
*Free Shipping on $50+
Swatch Image
SRAM GX DH Rear Derailleur
$114.00
SAVE 5 %
MSRP $120.00
Award Winner
*Free Shipping on $50+
Swatch Image
SRAM X01 DH Rear Derailleur
$257.00
SAVE 5 %
MSRP $271.00
*Free Shipping on $50+
Swatch Image
BOX Three Prime 9 X-Wide Rear Derailleur
$71.38
SAVE 11 %
MSRP $79.99
Award Winner
*Free Shipping on $50+
Swatch Image
BOX Two Prime 9 X-Wide Rear Derailleur
$107.78
SAVE 20 %
MSRP $134.99
Award Winner
*Free Shipping on $50+
Swatch Image
SRAM XX1 AXS Shifter 12 Speed OE Packaging
$129.99
SAVE 40 %
MSRP $215.00
*Free Shipping on $50+
 

Mountain Rear Derailleurs

Most mountain rear derailleurs share the same basic design, with two pivots (upper and lower) plus a cage and two pulleys for the chain to run through. The derailleur is bolted to the frame via a derailleur hanger. When you shift gears, it moves the chain up or down the rear sprockets. The shifter, usually positioned on the right side of the handlebars, either pulls a cable that moves the derailleur (on mechanical drivetrains) or, in the case of electronic drivetrains, communicates with the derailleur electronically.

Mountain rear derailleurs are designed to be more rugged than their road riding counterparts to withstand the wear and tear that goes with riding off-road. Their general look and design hasn’t changed much since the early days of the sport, but the internal workings have come a long way in recent years. While they still perform the same basic function that all rear derailleurs have for decades, most modern mountain bike rear derailleurs now have a clutch mechanism.

Regular rear derailleurs that don’t have a clutch rely solely on the tension of the main pivot to keep the chain in place — not always the best solution when riding rugged terrain at high speeds. The derailleur cage can bounce up and down, causing chain slap and sometimes a thrown chain. A clutch increases the tension of the pivot and prevents the cage from bouncing. The result is quieter, more reliable drivetrain performance — especially helpful with single chainring setups that are popular today.

When shopping for a new rear derailleur, the first thing to think about is compatibility. You need to know how many gears you have on your rear cassette so you can purchase a derailleur that matches. The most common options today are 10, 11 or 12-speed. We carry a wide variety of the top models from brands like Shimano, SRAM and Microshift, so call one of our Gear Advisors at 888-880-3811 if you have any questions about finding the perfect rear derailleur for your bike and riding style.