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SRAM · Mountain bike rear derailleur
Straightforward 8-speed MTB shifting with a durable, low-profile design.
$64.99
PriceIn stock, ready to ship
The SRAM X4 is a practical replacement rear derailleur for 8-speed mountain bike drivetrains, with 1:1 Actuation for direct cable movement and a long cage that supports cassettes up to 34T. Its low-profile shape and wide pivot help keep the derailleur tucked away while maintaining stable shifts.
Sold by Ashburton Cycles
Verified store
Price
$64.99
Speed
8-speed
Cage
Long cage
Maximum rear sprocket
34T
The SRAM X4 is a dependable mechanical rear derailleur for refreshing or repairing a compatible mountain bike drivetrain. This version is specified for 8-speed shifting, with compatibility across SRAM 7-, 8- and 9-speed systems when matched with the correct shifter and drivetrain components.
Its 1:1 Actuation moves the derailleur directly in response to cable movement, helping deliver consistent mechanical gear changes. The long cage handles a rear sprocket up to 34T, while the aluminium cage and steel pulley bearings provide a straightforward, serviceable construction.
The low-profile design helps reduce exposure to trail obstacles, and the wide pivot is designed to improve stiffness during shifts. Choose the X4 when you need an affordable SRAM replacement for a 7-, 8- or 9-speed setup, whether your drivetrain uses 1x, 2x or 3x chainrings.
A practical choice for anyone replacing a compatible SRAM 7-, 8- or 9-speed mountain bike rear derailleur without changing to a modern electronic or wide-range drivetrain.

1:1 Actuation
Direct cable movement provides predictable mechanical shifting when paired with a compatible SRAM shifter.
8-speed compatibility
Designed for 8-speed use, with the official specification also covering compatible 7- and 9-speed SRAM systems.
Long cage capacity
The long cage supports a rear sprocket up to 34T, making it suitable for a broad range of traditional MTB gearing.
Low-profile design
The compact shape keeps the derailleur tucked in to help reduce exposure to trail obstacles.
Wide pivot design
A wider pivot is designed to increase stiffness during shifts for more stable gear changes.
Aluminium cage
The aluminium cage offers a durable construction for everyday mountain bike use.
Steel pulley bearings
Steel pulley bearings provide a straightforward, robust solution for a serviceable mechanical drivetrain.
Broad drivetrain configuration
Compatible drivetrain configurations include 1x, 2x and 3x setups, subject to matching the rest of the drivetrain.
Sram XO rear derailleur overview and review
The Bike Channel with MongooseJake
Every detail as listed by the manufacturer.

SRAM is an American bicycle component manufacturer founded in Chicago in 1987. The company produces cycling components for road, gravel and mountain bikes, including drivetrains, brakes, suspension, wheels and electronic systems. SRAM began with Grip Shift gear-change technology and expanded through product development and acquisitions across the cycling component market. Its portfolio includes SRAM, RockShox, Avid, Truvativ, Zipp, Quarq, Hammerhead and other cycling brands.
SRAM · Mountain bike rear derailleur

Straightforward 8-speed MTB shifting with a durable, low-profile design.
$64.99
In stockSpeed
8-speed
Cage
Long cage
Maximum rear sprocket
34T
Cable pull ratio
1:1
The SRAM X4 is a practical replacement rear derailleur for 8-speed mountain bike drivetrains, with 1:1 Actuation for direct cable movement and a long cage that supports cassettes up to 34T. Its low-profile shape and wide pivot help keep the derailleur tucked away while maintaining stable shifts.
The SRAM X4 is a dependable mechanical rear derailleur for refreshing or repairing a compatible mountain bike drivetrain. This version is specified for 8-speed shifting, with compatibility across SRAM 7-, 8- and 9-speed systems when matched with the correct shifter and drivetrain components.
Its 1:1 Actuation moves the derailleur directly in response to cable movement, helping deliver consistent mechanical gear changes. The long cage handles a rear sprocket up to 34T, while the aluminium cage and steel pulley bearings provide a straightforward, serviceable construction.
The low-profile design helps reduce exposure to trail obstacles, and the wide pivot is designed to improve stiffness during shifts. Choose the X4 when you need an affordable SRAM replacement for a 7-, 8- or 9-speed setup, whether your drivetrain uses 1x, 2x or 3x chainrings.
A practical choice for anyone replacing a compatible SRAM 7-, 8- or 9-speed mountain bike rear derailleur without changing to a modern electronic or wide-range drivetrain.
1:1 Actuation
Direct cable movement provides predictable mechanical shifting when paired with a compatible SRAM shifter.
8-speed compatibility
Designed for 8-speed use, with the official specification also covering compatible 7- and 9-speed SRAM systems.
Long cage capacity
The long cage supports a rear sprocket up to 34T, making it suitable for a broad range of traditional MTB gearing.
Low-profile design
The compact shape keeps the derailleur tucked in to help reduce exposure to trail obstacles.
Wide pivot design
A wider pivot is designed to increase stiffness during shifts for more stable gear changes.
Aluminium cage
The aluminium cage offers a durable construction for everyday mountain bike use.
Steel pulley bearings
Steel pulley bearings provide a straightforward, robust solution for a serviceable mechanical drivetrain.
Broad drivetrain configuration
Compatible drivetrain configurations include 1x, 2x and 3x setups, subject to matching the rest of the drivetrain.
Sram XO rear derailleur overview and review
The Bike Channel with MongooseJake