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 
Shimano 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 hub bolt 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.
$16.99 
Buy on Amazon SaleBestseller No. 2 
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
$14.60
Buy on Amazon Bestseller No. 3 
MEGHNA Shimano Tourney RD-TY300 6/7-Speed Rear Derailleur Road MTB Bike Mountain 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 and so on.
- 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.
- Long cage tourney derailleur, compatible with 11T /14T high speed gear.
$21.59
Buy on Amazon 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.
$17.99
Buy on Amazon SaleBestseller No. 5 
Schwinn GTX 2.0 Comfort Adult Hybrid Bike for Men and Women, Dual Sport Bicycle, 700c Wheels, 18-Inch Step-Over Aluminum Frame, 21-Speed Twist Shifters, Mechanical Disc Brake, Black/Blue
- Hybrid bike with an aluminum dual-sport frame and suspension fork that offers limitless adaptability, 700c wheels that fit to riders 5’7” – 6’2” tall
- Adult mountain bike is equipped with 21-speed twist shifters, ensuring effortless and accurate gear adjustments
- Mechanical disc brakes offer enhanced stopping power, providing you with additional control and braking performance
- Enabling precise riding, the handlebar and stem combination strikes a balance between lightweight design and durability
- Triple-density ergonomic grips and sport saddle touch key comfort points to soften the ride
$449.99
Buy on Amazon Bestseller No. 6 
Inkesky RD-TZ31-GS 6/7 Speed Rear Derailleur with Direct Mount, Medium Cage, for Mountain Bike
- 【Model】 Tourney (SIS) RD-TZ31-GS 6/7 speed，medium-cage , direct mount, Compatible with Shimano driven system.No retail packaging. Items as shown
$16.88
Buy on Amazon Bestseller No. 7 
ZUKKA Shimano Rear Derailleur RD-TZ31-A 6/7 Speed Hanger Mount for MTB Mountain Road Bike
- MODEL: RD-TZ31-A bike rear derailleur, Compatible with 6 and 7-speed SIS Index Shifting drivetrains.
- IMPORTANT: The bike rear derailleur is hanger mount (hub bolt mount), 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.
$16.69
Buy on Amazon SaleBestseller No. 8 
Shimano Tourney TY300 6/7-Speed Rear Derailleur Direct-Attach
- Long cage design accommodates up to 34T cassette
- SIS indexing for smooth reliable performance
- 6/7-speed compatible
$14.11
Buy on Amazon SaleBestseller No. 9 
Bicycle Rear Derailleur Hanger Racing Cycling MTB Road Bike Frame Gear Parts Dropout Adapter WG008-SL Silver 2.24x1.38''
- Material: Aluminum alloy;
- Wide Range of Applications: Suitable for most types of mountain bike and road bike;
- Effective Protection: After fixed on the rack, it can protect the transmission after dialing;
- Easy to Install: The upper end of the tail hook is connected with the frame, and the lower end is connected with the rear dial of the transmission;
- Notice: Please compare the parts you need to replace to see if their size and shape match.
$10.70
Buy on Amazon Bestseller No. 10 
THALOUS Bicycle Rear Derailleur Tourney RD-TY21B 6/7 Speed for MTB Bike Direct Mount/Hanger Mount
- 【MODEL】Bicycle rear derailleur RD-TY21B, suitable for 6-speed and 7-speed SIS index variable speed drives. Please pay attention to the speed when buying.
- 【Hook mounted】Before purchasing, please confirm whether the rear derailleur of your bicycle is directly installed or hook mounted. This model is a Hook mounted method.
- 【High-quality material】This bicycle rear derailleur is made of high-quality steel, sturdy and durable, not easily deformed and not easily damaged.
- 【Wide application】This bicycle transmission is suitable for variable speed bikes, mountain bikes, road bikes, bicycle racing, 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.
Bestselling Mountain Bike Rear Derailleurs
SaleBestseller No. 1
Shimano 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 hub bolt 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.
$16.99
Buy on Amazon SaleBestseller No. 2
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
$14.60
Buy on Amazon Bestseller No. 3
MEGHNA Shimano Tourney RD-TY300 6/7-Speed Rear Derailleur Road MTB Bike Mountain 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 and so on.
- 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.
- Long cage tourney derailleur, compatible with 11T /14T high speed gear.
$21.59
Buy on Amazon 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.
$17.99
Buy on Amazon Bestseller No. 5
Inkesky RD-TZ31-GS 6/7 Speed Rear Derailleur with Direct Mount, Medium Cage, for Mountain Bike
- 【Model】 Tourney (SIS) RD-TZ31-GS 6/7 speed，medium-cage , direct mount, Compatible with Shimano driven system.No retail packaging. Items as shown
$16.88
Buy on Amazon Bestseller No. 6
ZUKKA Shimano Rear Derailleur RD-TZ31-A 6/7 Speed Hanger Mount for MTB Mountain Road Bike
- MODEL: RD-TZ31-A bike rear derailleur, Compatible with 6 and 7-speed SIS Index Shifting drivetrains.
- IMPORTANT: The bike rear derailleur is hanger mount (hub bolt mount), 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.
$16.69
Buy on Amazon SaleBestseller No. 7
Shimano Tourney TY300 6/7-Speed Rear Derailleur Direct-Attach
- Long cage design accommodates up to 34T cassette
- SIS indexing for smooth reliable performance
- 6/7-speed compatible
$14.11
Buy on Amazon SaleBestseller No. 8
Bicycle Rear Derailleur Hanger Racing Cycling MTB Road Bike Frame Gear Parts Dropout Adapter WG008-SL Silver 2.24x1.38''
- Material: Aluminum alloy;
- Wide Range of Applications: Suitable for most types of mountain bike and road bike;
- Effective Protection: After fixed on the rack, it can protect the transmission after dialing;
- Easy to Install: The upper end of the tail hook is connected with the frame, and the lower end is connected with the rear dial of the transmission;
- Notice: Please compare the parts you need to replace to see if their size and shape match.
$10.70
Buy on Amazon Bestseller No. 9
THALOUS Bicycle Rear Derailleur Tourney RD-TY21B 6/7 Speed for MTB Bike Direct Mount/Hanger Mount
- 【MODEL】Bicycle rear derailleur RD-TY21B, suitable for 6-speed and 7-speed SIS index variable speed drives. Please pay attention to the speed when buying.
- 【Hook mounted】Before purchasing, please confirm whether the rear derailleur of your bicycle is directly installed or hook mounted. This model is a Hook mounted method.
- 【High-quality material】This bicycle rear derailleur is made of high-quality steel, sturdy and durable, not easily deformed and not easily damaged.
- 【Wide application】This bicycle transmission is suitable for variable speed bikes, mountain bikes, road bikes, bicycle racing, 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.
Top Shimano Mountain Bike Derailleurs
SaleBestseller No. 1
Shimano 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 hub bolt 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.
$16.99
Buy on Amazon SaleBestseller No. 2
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
$14.60
Buy on Amazon Bestseller No. 3
MEGHNA Shimano Tourney RD-TY300 6/7-Speed Rear Derailleur Road MTB Bike Mountain 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 and so on.
- 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.
- Long cage tourney derailleur, compatible with 11T /14T high speed gear.
$21.59
Buy on Amazon Bestseller No. 4
ZUKKA Shimano Rear Derailleur RD-TZ31-A 6/7 Speed Hanger Mount for MTB Mountain Road Bike
- MODEL: RD-TZ31-A bike rear derailleur, Compatible with 6 and 7-speed SIS Index Shifting drivetrains.
- IMPORTANT: The bike rear derailleur is hanger mount (hub bolt mount), 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.
$16.69
Buy on Amazon SaleBestseller No. 5
Shimano Tourney TY300 6/7-Speed Rear Derailleur Direct-Attach
- Long cage design accommodates up to 34T cassette
- SIS indexing for smooth reliable performance
- 6/7-speed compatible
$14.11
Buy on Amazon
How To Set Up A Mountain Bike Derailleur
