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 
MEGHNA RD-TY300 6/7 Speed Rear Derailleur for Hybrid Bike Folding Bike Mountain Bike Tricycle E-Bike Direct Mount
- Model: RD-TY300-SGS; Bike Rear Derailleur 6/7 Speed for most kinds of bikes like mountain bike, hybrid bike, kids bike, cruiser bike etc.
- Features: Smooth shifting, easy and fast to install. Bracket fit (under wheel nut) Long cage tourney derailleur, total capacity 43T, pulley/Teeth 13/13T. Low sprocket: Max. 34T; Low sprocket: Min. 28T; Top sprocket: Max. 14T; Top sprocket: Min. 11T.
- Stability: Made of high quality durable aluminum alloy material and come with excellent shifting performance ensure your safe and stable while riding.
- Application: Compatible with 6 and 7-speed SIS INDEX variable speed transmission systems. Suitable for MTB, mountain bikes, road bikes, folding bicycles, commuter bikes, tricycles, eletric bikes etc.
- Type: Long cage tourney derailleur, compatible with 11T /14T high speed gear.
$17.53 
Buy on Amazon Bestseller No. 2 
MEGHNA Bike Rear Derailleur RD-TZ31-A 6/7 Speed Direct Mount Rear Derailleur for Mountain Bike Tricycle Commuter Bike Folding Bike
- Model: RD-TZ31-A; Bike rear derailleur, compatible with 6/7 speed mountain bikes, commuter bike, tricycle, folding bike etc.
- Note: The bike rear derailleur is direct mount, not hanger mount. Please choose right mount way before you purchase.
- Stability: Made of high quality durable aluminum alloy material and come with excellent shifting performance ensure your safe and stable while riding.
- Application: Suitable for MTB, mountain bikes, road bikes, folding bicycles, commuter bikes, tricycles, eletric bikes etc.
- Important: We provide excellent customer service, please feel free to contact if you have any questions.
$16.80
Buy on Amazon Bestseller No. 3 
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
Bestseller No. 4 
Hycline Bike Rear Derailleur RD-TY21B 6/7 Speed Hanger Mount for Mountain Bicycle-Black
- MODEL: RD-TY21B Black Rear Derailleur,Suitable for 6/7speed.
- PERFORMANCE:Forged with high hardness aluminum alloy.The hollow weight-reduction design is adopted,and the speed change is more stable.
- PRECISE ADJUSTMENT: High-hardness aluminum alloy body adjustment, adjustment is more precise. It can be adjusted slightly in multiple places to ensure accurate speed change performance.
- INSTALLATION:Fast and convenient installation and easy maintenance.(Note:The bike rear derailleur is hub bolt mount,not direct mount .Please check the mount type of the original part before ordering.)
- SCOPE OF APPLICATION:Suitable for mountain bikes, station wagons, folding bikes, etc.If you have any questions,please feel free to contact us.We will provide timely response and quality service.
$14.99
Buy on Amazon Bestseller No. 5 
MOHEGIA 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: With 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.
$12.99
Buy on Amazon Bestseller No. 6 
Inkesky RD-TZ31-GS 6/7 Speed Rear Derailleur with Direct Mount, Medium Cage, for Mountain Bike
- [IMPORTANT] It's Direct Mount Rear Derailleur for Mountain Bike, not Hanger mount
$16.38
Buy on Amazon Bestseller No. 7 
THALOUS Bicycle Rear Derailleur 6/7/8 Speed Tourney RD-TY300 RD-TX800 Altus RD-M310 for MTB Bike Direct Mount
- MODEL: Bicycle rear derailleur Tourney RD-TY300, suitable for 6-speed,7-speed and 8-speed SIS index variable speed drives
- Direct installation: Before purchasing, please confirm whether the rear derailleur of your bicycle is directly installed or hook mounted
- High-quality material: This bicycle rear derailleur is made of high-quality Aluminium alloy, sturdy and durable, not easily deformed and not easily damaged.
- Wide application: This bicycle transmission is suitable for variable speed bikes, such as mountain bikes, road bikes, racing bikes, city bikes, folding bikes, etc. Is a good helper for your riding.
- Professional customer service: If you have any questions about our products or services, please feel free to contact us, we will provide you with professional services.
$17.29
Buy on Amazon Bestseller No. 8 
Sunrace Sgs Rear Friction Derailleur w/Braket: Rdm10, Silver
- Friction derailleur
- Affordable replacement
- Wrap: 35
- Cage/Mount: Long w/Hgr
- Ratio: 2to1
SaleBestseller No. 9 
THALOUS Bicycle Rear Derailleur RD-TZ31-A Tourney 6/7 Speed for MTB Bike Direct Mount
- Model: Bicycle rear derailleur RD-TZ31-A,suitable for 6 speed and 7 speed SIS index variable speed drives.
- Direct mount: The installation method is Direct mount, NOT hanger mount(hook holder)
- High-quality material: Made of high-quality steel, sturdy and durable, not easily deformed and not easily damaged.
- Wonderful performance: The guide wheel of the rear derailleur is smooth and silent, the shifting is smooth, and the chain will not be damaged, making the riding easy and comfortable.
- Wide application: This bicycle transmission is suitable for variable speed bikes, mountain bikes, road bikes, bicycle racing, city bikes, folding bikes, etc.
$15.59
Buy on Amazon SaleBestseller No. 10 
THALOUS Bicycle Rear Derailleur Tourney RD-TY21B 6 7 Speed for MTB Mountain Bike Direct Mount Hanger Mount
- Model: Bicycle rear derailleur RD-TY21B, suitable for 6 speed and 7 speed SIS index variable speed drives
- Hanger installation: Before purchasing, please confirm whether the rear derailleur of your bicycle is directly installed or hook mounted(hanger mount).
- High-quality material: Made of durable aluminum alloy material, which ensures your safe and stable on the ride, not easily deformed and pretty solid
- Wide application: This bicycle transmission is suitable for variable speed bikes, mountain bikes, road bikes, bicycle racing, city bikes, folding bikes, etc.
- Professional customer service: If you have any questions about our products or services, please feel free to contact us, we will provide you with our professional service
$12.98
Buy on AmazonBestselling Mountain Bike Rear Derailleurs
SaleBestseller No. 1
MEGHNA RD-TY300 6/7 Speed Rear Derailleur for Hybrid Bike Folding Bike Mountain Bike Tricycle E-Bike Direct Mount
- Model: RD-TY300-SGS; Bike Rear Derailleur 6/7 Speed for most kinds of bikes like mountain bike, hybrid bike, kids bike, cruiser bike etc.
- Features: Smooth shifting, easy and fast to install. Bracket fit (under wheel nut) Long cage tourney derailleur, total capacity 43T, pulley/Teeth 13/13T. Low sprocket: Max. 34T; Low sprocket: Min. 28T; Top sprocket: Max. 14T; Top sprocket: Min. 11T.
- Stability: Made of high quality durable aluminum alloy material and come with excellent shifting performance ensure your safe and stable while riding.
- Application: Compatible with 6 and 7-speed SIS INDEX variable speed transmission systems. Suitable for MTB, mountain bikes, road bikes, folding bicycles, commuter bikes, tricycles, eletric bikes etc.
- Type: Long cage tourney derailleur, compatible with 11T /14T high speed gear.
$17.53
Buy on Amazon Bestseller No. 2
MEGHNA Bike Rear Derailleur RD-TZ31-A 6/7 Speed Direct Mount Rear Derailleur for Mountain Bike Tricycle Commuter Bike Folding Bike
- Model: RD-TZ31-A; Bike rear derailleur, compatible with 6/7 speed mountain bikes, commuter bike, tricycle, folding bike etc.
- Note: The bike rear derailleur is direct mount, not hanger mount. Please choose right mount way before you purchase.
- Stability: Made of high quality durable aluminum alloy material and come with excellent shifting performance ensure your safe and stable while riding.
- Application: Suitable for MTB, mountain bikes, road bikes, folding bicycles, commuter bikes, tricycles, eletric bikes etc.
- Important: We provide excellent customer service, please feel free to contact if you have any questions.
$16.80
Buy on Amazon Bestseller No. 3
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
Bestseller No. 4
Hycline Bike Rear Derailleur RD-TY21B 6/7 Speed Hanger Mount for Mountain Bicycle-Black
- MODEL: RD-TY21B Black Rear Derailleur,Suitable for 6/7speed.
- PERFORMANCE:Forged with high hardness aluminum alloy.The hollow weight-reduction design is adopted,and the speed change is more stable.
- PRECISE ADJUSTMENT: High-hardness aluminum alloy body adjustment, adjustment is more precise. It can be adjusted slightly in multiple places to ensure accurate speed change performance.
- INSTALLATION:Fast and convenient installation and easy maintenance.(Note:The bike rear derailleur is hub bolt mount,not direct mount .Please check the mount type of the original part before ordering.)
- SCOPE OF APPLICATION:Suitable for mountain bikes, station wagons, folding bikes, etc.If you have any questions,please feel free to contact us.We will provide timely response and quality service.
$14.99
Buy on Amazon Bestseller No. 5
MOHEGIA 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: With 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.
$12.99
Buy on Amazon Bestseller No. 6
Inkesky RD-TZ31-GS 6/7 Speed Rear Derailleur with Direct Mount, Medium Cage, for Mountain Bike
- [IMPORTANT] It's Direct Mount Rear Derailleur for Mountain Bike, not Hanger mount
$16.38
Buy on Amazon Bestseller No. 7
THALOUS Bicycle Rear Derailleur 6/7/8 Speed Tourney RD-TY300 RD-TX800 Altus RD-M310 for MTB Bike Direct Mount
- MODEL: Bicycle rear derailleur Tourney RD-TY300, suitable for 6-speed,7-speed and 8-speed SIS index variable speed drives
- Direct installation: Before purchasing, please confirm whether the rear derailleur of your bicycle is directly installed or hook mounted
- High-quality material: This bicycle rear derailleur is made of high-quality Aluminium alloy, sturdy and durable, not easily deformed and not easily damaged.
- Wide application: This bicycle transmission is suitable for variable speed bikes, such as mountain bikes, road bikes, racing bikes, city bikes, folding bikes, etc. Is a good helper for your riding.
- Professional customer service: If you have any questions about our products or services, please feel free to contact us, we will provide you with professional services.
$17.29
Buy on Amazon Bestseller No. 8
Sunrace Sgs Rear Friction Derailleur w/Braket: Rdm10, Silver
- Friction derailleur
- Affordable replacement
- Wrap: 35
- Cage/Mount: Long w/Hgr
- Ratio: 2to1
SaleBestseller No. 9
THALOUS Bicycle Rear Derailleur RD-TZ31-A Tourney 6/7 Speed for MTB Bike Direct Mount
- Model: Bicycle rear derailleur RD-TZ31-A,suitable for 6 speed and 7 speed SIS index variable speed drives.
- Direct mount: The installation method is Direct mount, NOT hanger mount(hook holder)
- High-quality material: Made of high-quality steel, sturdy and durable, not easily deformed and not easily damaged.
- Wonderful performance: The guide wheel of the rear derailleur is smooth and silent, the shifting is smooth, and the chain will not be damaged, making the riding easy and comfortable.
- Wide application: This bicycle transmission is suitable for variable speed bikes, mountain bikes, road bikes, bicycle racing, city bikes, folding bikes, etc.
$15.59
Buy on Amazon SaleBestseller No. 10
THALOUS Bicycle Rear Derailleur Tourney RD-TY21B 6 7 Speed for MTB Mountain Bike Direct Mount Hanger Mount
- Model: Bicycle rear derailleur RD-TY21B, suitable for 6 speed and 7 speed SIS index variable speed drives
- Hanger installation: Before purchasing, please confirm whether the rear derailleur of your bicycle is directly installed or hook mounted(hanger mount).
- High-quality material: Made of durable aluminum alloy material, which ensures your safe and stable on the ride, not easily deformed and pretty solid
- Wide application: This bicycle transmission is suitable for variable speed bikes, mountain bikes, road bikes, bicycle racing, city bikes, folding bikes, etc.
- Professional customer service: If you have any questions about our products or services, please feel free to contact us, we will provide you with our professional service
$12.98
Buy on AmazonTop Shimano Mountain Bike Derailleurs
Bestseller No. 1
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. 2 
Shimano Tourney RD-TY300-SGS 6/7-Speed Mountain Bicycle Rear Derailleur , Black, One Size
- Shimano TX35 6 / 7-speed rear derailleur (bracket attachment)
- SIS rear index shifting
- SGS cage can handle wide range gearing and 34 tooth sprockets
- 13 tooth pulleys offer long service life and less noise
Bestseller No. 3 
Shimano Deore SGS RD-M592 Rear Derailleur (9-Speed, Long Cage, Black)
- Precise chain movement changes gears smoothly
- Direct Mount
- Light shift effort
$62.35
Buy on Amazon Bestseller No. 4 
Shimano Acera RD-M3020-SGS Rear Derailleur - 7/8 Speed, Long Cage, Black
- Double Servo mechanism enables the rear derailleur to move in an optimum path
- Versatile performance and wide compatibility
- SGS Long cage
- Chain Wrap Capacity (teeth): 45
- Drivetrain Speeds: 7,8
How To Set Up A Mountain Bike Derailleur
