Rear derailleur is something I’d never thought I’d say outloud. However, if you’ve been moutain biking for any length of time you’ve probably had to adjust the mountain bike derailleurs. What’s a derailleur you might ask! It’s a fancy sounding name for the thing that adjusts the it’s position to keep the tension on the chain as you change gears. If you’re bike cost under $1,000 you probably need to upgrade that mountian bike derailler. Just like our review of chain tensioners, you’ll find that there are a plethora of choices when you want to select the best mountain bike derailleur. You can purchase a decent bike frame from a local store and then upgrade the parts and have a pretty solid mountain bike.
Best Mountain Bike Derailleurs
What you will learn in this Article
SaleBestseller No. 1 
Bike Rear Derailleur RD-TY21B 6/7 Speed Direct Mount for Mountain Bicycle-Black
- Model：RD-TY21B rear derailleur compatible with 6/7 speed mountain bikes.
- Note:The rear derailleur is direct mount,not hub bolt mount .Please check the mount type of the original part before ordering.
- Stability: Durable aluminum alloy material and excellent shifting performance ensure safe and stable riding.
- Wide application: Rear derailleur is easy to use and maintain.Suitable for MTB,mountain bikes, road bikes, folding bicycles and so on.
- Important: Please feel free to contact if you have any questions, we will provide quality service.
SaleBestseller No. 2 
SHIMANO Tourney 7/8-Speed Mountain Bicycle Rear Derailleur - RD-TX800-L (Black)
- Tourney RD-TX800 Rear Derailleur
SaleBestseller No. 4 
Shimano Tourney TY300 6/7-Speed Rear Derailleur with Dropout Claw Hanger
- Includes frame hanger
- Largest Cog: 34
- Chain Wrap Capacity: 43
- Cage Length: Long
- keyword search: Replaces rd8162
SaleBestseller No. 5 
Shimano RDM310DL Altus GS 7/8-speed Rear Der Black,Long Cage
- Chain Wrap Capacity: 43teeth, Derailleur Action: Top-Normal (Traditional)
- Derailleur Color: black, Drivetrain Spacing: Shimano/SRAM 8, Largest Cog: 34teeth
- Shifter/Rear Derailleur : Shimano, Speeds: 8sp, Weight: 326g
SaleBestseller No. 6 
Sram Unisex - Adult XX1 Eagle AXS Rear Derailleur, Black, One Size
- Technical data:
- Use: MTB
- Installation: direct mounting
- System compatibility: 12-speed
- Design: long cage
Bestseller No. 7 
ZUKKA Bike Rear Derailleur-RD-TZ31-A 6/7 Speed Hub Bolt Mount (Hanger Mount) for MTB Mountain,Road,Variable Speed,Folding,City Bicycles/Black
- MODEL:RD-TZ31-A bike rear derailleur, Compatible with 6 and 7-speed SIS Index Shifting drivetrains.
- IMPORTANT : The hub bolt mount （hanger mount) rear derailleur for mountain bike, not direct mount.
- EXCELLENT PERFORMANCE:Accurate gears provide light and stable shift performance,and making riding easy and comfortable.
- MATERIAL:Made of high-quality steel materials,durable and long service life.Easy to install and disassemble.
- APPLICATION: Suitable for MTB mountain bike ,road bikes ,variable speed bicycle,folding and city bikes.It is your indispensable bicycle accessories during your cycling journey.
SaleBestseller No. 8 
Cannondale Mountain Rear Derailleur Hanger Kit KP284
- Details:Compatible with the Cannondale Trail 15-19, Adventure 17-19, Bad Boy 16-19, Catalyst 16-19, Contro 15-16, Cujo 17-19, Foray 17-19, Kids Cujo, Kids Trail, Kids Quick, Kids Street, Kinneto, Law Enforcement, Mavaro Neo, Quick 16-19, Quick CX 15-19, Quick Neo 18, Scarlet, Tango16-19, Tesoro Neo, TreadwellThis solid derailleur hanger is designed to keep the derailleur stabilized during the roughest riding conditionsComes with hanger and mounting hardware (2 screws)
SaleBestseller No. 9 
SHIMANO Dura-Ace Di2 RD-R9150 11-Speed Rear Derailleur Black, One Size
- Pull Type: electronic
- Cage Length: [SS] short
- Capacity: 33T
- Cassette Range: [minimum] 11T, [maximum] 30T
- Gearing: 2x11
Bestseller No. 10 
MEGHNA Shimano Tourney RD-TY300 6/7-Speed Rear Derailleur Road MTB Bike Mountain Bike Direct Mount
- Smooth shifting, easy and fast to install. Bracket fit (under wheel nut) Long cage tourney derailleur, compatible with 11T /14T high speed gear
- Rear derailleur, compatible with 6 and 7-speed SIS INDEX variable speed transmission systems
- B tension adjustment screw, so that the distance between the upper guide wheel and the tooth tip of the largest flywheel can not be less than 6mm
- Max Sprocket 34T. Min Sprocket 11T
- Long cage tourney derailleur, compatible with 11T /14T high speed gear
Bestselling Mountain Bike Rear Derailleurs
SaleBestseller No. 1
Bike Rear Derailleur RD-TY21B 6/7 Speed Direct Mount for Mountain Bicycle-Black
- Model：RD-TY21B rear derailleur compatible with 6/7 speed mountain bikes.
- Note:The rear derailleur is direct mount,not hub bolt mount .Please check the mount type of the original part before ordering.
- Stability: Durable aluminum alloy material and excellent shifting performance ensure safe and stable riding.
- Wide application: Rear derailleur is easy to use and maintain.Suitable for MTB,mountain bikes, road bikes, folding bicycles and so on.
- Important: Please feel free to contact if you have any questions, we will provide quality service.
SaleBestseller No. 2
SHIMANO Tourney 7/8-Speed Mountain Bicycle Rear Derailleur - RD-TX800-L (Black)
- Tourney RD-TX800 Rear Derailleur
SaleBestseller No. 4
Shimano Tourney TY300 6/7-Speed Rear Derailleur with Dropout Claw Hanger
- Includes frame hanger
- Largest Cog: 34
- Chain Wrap Capacity: 43
- Cage Length: Long
- keyword search: Replaces rd8162
SaleBestseller No. 5
Shimano RDM310DL Altus GS 7/8-speed Rear Der Black,Long Cage
- Chain Wrap Capacity: 43teeth, Derailleur Action: Top-Normal (Traditional)
- Derailleur Color: black, Drivetrain Spacing: Shimano/SRAM 8, Largest Cog: 34teeth
- Shifter/Rear Derailleur : Shimano, Speeds: 8sp, Weight: 326g
SaleBestseller No. 6
Sram Unisex - Adult XX1 Eagle AXS Rear Derailleur, Black, One Size
- Technical data:
- Use: MTB
- Installation: direct mounting
- System compatibility: 12-speed
- Design: long cage
Bestseller No. 7
ZUKKA Bike Rear Derailleur-RD-TZ31-A 6/7 Speed Hub Bolt Mount (Hanger Mount) for MTB Mountain,Road,Variable Speed,Folding,City Bicycles/Black
- MODEL:RD-TZ31-A bike rear derailleur, Compatible with 6 and 7-speed SIS Index Shifting drivetrains.
- IMPORTANT : The hub bolt mount （hanger mount) rear derailleur for mountain bike, not direct mount.
- EXCELLENT PERFORMANCE:Accurate gears provide light and stable shift performance,and making riding easy and comfortable.
- MATERIAL:Made of high-quality steel materials,durable and long service life.Easy to install and disassemble.
- APPLICATION: Suitable for MTB mountain bike ,road bikes ,variable speed bicycle,folding and city bikes.It is your indispensable bicycle accessories during your cycling journey.
SaleBestseller No. 8
Cannondale Mountain Rear Derailleur Hanger Kit KP284
- Details:Compatible with the Cannondale Trail 15-19, Adventure 17-19, Bad Boy 16-19, Catalyst 16-19, Contro 15-16, Cujo 17-19, Foray 17-19, Kids Cujo, Kids Trail, Kids Quick, Kids Street, Kinneto, Law Enforcement, Mavaro Neo, Quick 16-19, Quick CX 15-19, Quick Neo 18, Scarlet, Tango16-19, Tesoro Neo, TreadwellThis solid derailleur hanger is designed to keep the derailleur stabilized during the roughest riding conditionsComes with hanger and mounting hardware (2 screws)
SaleBestseller No. 9
SHIMANO Dura-Ace Di2 RD-R9150 11-Speed Rear Derailleur Black, One Size
- Pull Type: electronic
- Cage Length: [SS] short
- Capacity: 33T
- Cassette Range: [minimum] 11T, [maximum] 30T
- Gearing: 2x11
Bestseller No. 10
MEGHNA Shimano Tourney RD-TY300 6/7-Speed Rear Derailleur Road MTB Bike Mountain Bike Direct Mount
- Smooth shifting, easy and fast to install. Bracket fit (under wheel nut) Long cage tourney derailleur, compatible with 11T /14T high speed gear
- Rear derailleur, compatible with 6 and 7-speed SIS INDEX variable speed transmission systems
- B tension adjustment screw, so that the distance between the upper guide wheel and the tooth tip of the largest flywheel can not be less than 6mm
- Max Sprocket 34T. Min Sprocket 11T
- Long cage tourney derailleur, compatible with 11T /14T high speed gear
Top Shimano Mountain Bike Derailleurs
SaleBestseller No. 1
SHIMANO Tourney 7/8-Speed Mountain Bicycle Rear Derailleur - RD-TX800-L (Black)
- Tourney RD-TX800 Rear Derailleur
SaleBestseller No. 3
Shimano Tourney TY300 6/7-Speed Rear Derailleur with Dropout Claw Hanger
- Includes frame hanger
- Largest Cog: 34
- Chain Wrap Capacity: 43
- Cage Length: Long
- keyword search: Replaces rd8162
SaleBestseller No. 4
Shimano RDM310DL Altus GS 7/8-speed Rear Der Black,Long Cage
- Chain Wrap Capacity: 43teeth, Derailleur Action: Top-Normal (Traditional)
- Derailleur Color: black, Drivetrain Spacing: Shimano/SRAM 8, Largest Cog: 34teeth
- Shifter/Rear Derailleur : Shimano, Speeds: 8sp, Weight: 326g
SaleBestseller No. 5
SHIMANO Dura-Ace Di2 RD-R9150 11-Speed Rear Derailleur Black, One Size
- Pull Type: electronic
- Cage Length: [SS] short
- Capacity: 33T
- Cassette Range: [minimum] 11T, [maximum] 30T
- Gearing: 2x11
How To Set Up A Mountain Bike Derailleur
