The 10 Best Mountain Bike Derailleurs with Buying Guide

If you take mountain biking seriously, then you need to keep an eye on the quality of all the components of your mountain bike. With time, some of them will need to be replaced and it is a good idea to learn to do this on your own. The Best Mountain Bike Derailleurs will improve your mountain biking experience as they guarantee that your MTB will stay responsive in all conditions. Here’s the quick answer for you:

Top 10 Mountain Bike Derailleurs of 2019

  1. Shimano Deore XT Shadow Rear Derailleur
  2. Shimano Deore 9-Speed Rear Derailleur
  3. Shimano Acera RD-410 Rear Derailleur
  4. SRAM X.9 Rear Bicycle Derailleur
  5. SRAM X5 9-Speed Rear Derailleur
  6. SRAM GX Bicycle Rear Derailleur
  7. Shimano Rd-tz 31 Rear Derailleur
  8. SRAM X4 8-Speed Rear Derailleur
  9. Shimano Tourney 7/8-Speed Rear Derailleur
  10. Shimano Rear Derailleur RD-TX35

A bike derailleur is a device that allows you to change gears by moving the chain. This means that you can go very fast on smooth trails or can go slow on uphill paths. Every mountain bike has a rear derailleur and a front one. If you start to feel that your bike’s transmission is not as smooth as you need it to be, then it is time to have your derailleurs replaced.

What is the Difference between the Front and Rear Derailleurs?

The rear derailleur has two main jobs. The first one is to keep the chain tense and the second one is to switch gears. When you pedal the bike, the power of pedaling pulls the chain tight. The derailleur then keeps the lower part of the chain in the right sprocket. The front derailleur moves the top part of the chain.

Tourney Bike Derailleurs

For your MTB to function properly, you want to make sure that both the front and rear derailleur are in perfect condition. In this guide, we focus on rear derailleurs that guarantee the swift and flawless shifting of the gears on your MTB.

Reviews of the Best Mountain Bike Derailleurs

If you are not a professional, you might not be able to pick the best bike derailleur. This is why we asked several experts about their opinions and they helped by reviewing some of the best-sellers on the market. By reading this section, you will be able to pick the right addition to your mountain bike. Every best mountain bike rear derailleur review contains valuable information about the description in addition to the pros and cons of each model.

1. Shimano Deore XT Shadow Mountain Bicycle Rear Derailleur – RD-M772

This simple and low-profile rear derailleur is designed to improve the performance of your bike. It is compatible with 9-speed bikes and won’t hit the chain. It is made of lightweight yet durable aluminum and this means that it won’t rust or show any signs of wear.

This rear derailleur weighs around 220 grams and doesn’t slow you down. As a matter of fact, it is one of the best additions to your MTB if you want to improve its performance. It features direct routing to reduce the risk of snagging as you change gears. It also features a strong return spring that will allow for a crisp feeling while shifting. It shifts quickly, smoothly and quietly. It is a versatile derailleur that can work with different cross country and trekking mountain bikes.


  • Durable aluminum derailleur.
  • Lightweight design.
  • Direct routing to reduce snagging.
  • Allows for smooth and quiet shifting.


  • Tends to get a bit sluggish in cold weather.

2. Shimano Deore 9-Speed Mountain Bicycle Rear Derailleur – RD-M591

When you are looking for a good MTB derailleur, you want to make sure that you are buying an affordable yet durable piece of equipment. This excellent derailleur provides quick and precise shifting. It is also very durable and reliable thus offering outstanding performance in all conditions.

This rear derailleur weighs less than 300 grams yet can help you shift gears in all terrains. It is compatible with various 9-speed MTBs and is very easy to install. You can also use it with your 7-speed bike with no problems whatsoever. You don’t have to be an expert because it is very easy to install. The pin bushings are fluorine-coated. This guarantees that your rear derailleur will last for long. This coating protects the derailleur from humidity that can cause rust thus affecting the shifting of the gears. It is easy to adjust for flawless and silent operation.


  • Affordable rear derailleur.
  • Fluorine-coated.
  • Easy to install and adjust.
  • Precise and quiet shifting.
  • Compatible with various MTBs regardless of their speed.
  • Good value for the money.


  • Might get a little bent but you can easily bend it back for a flawless performance.

3. Shimano Acera RD-410 Mountain Bike Rear Derailleur

This is a budget-friendly rear derailleur that will instantly improve the shifting on your MTB. It is compatible with 8-speed mountain bikes and is the perfect combination of an affordable price and flawless performance.

The derailleur is made of steel and aluminum for the best performance. It is the best rear derailleur with low-friction for smooth and crisp shifting. The design of the rear derailleur allows for excellent shifting under heavy load and maximum acceleration. This is a lightweight derailleur for easy and precise shifting. It even features SGS long cage design for a wide range of gear shifting. The oversized tooth pulleys guarantee that this derailleur won’t malfunction. This is the best budget mountain bike derailleur and is very easy to mount and adjust.


  • Budget-friendly rear derailleur.
  • Made of aluminum and steel.
  • The best combination a good price and high-quality performance.
  • Excellent shifting at maximum acceleration.
  • Wide range of gear shifting.
  • Easy to mount and adjust.


  • It is a little clunky.

4. SRAM X.9 Rear Bicycle Derailleur

If you want to install the best mountain bike rear derailleur, then you need to give this one a try. It is made up of aluminum alloy links and B-knuckles in addition to aluminum and composite cages. This guarantees maximum durability and performance because you know that your derailleur will last for long.

This lightweight rear derailleur weighs almost 200 grams. This means that it won’t slow you down or affect your speed whether you are going up or downhill. It is the perfect rear derailleur for precise and smooth shifting on all trails. The cage is polished to protect the derailleur from the elements. This guarantees that it will last for long with no risk of rust or wear. It is compatible with various 9-speed bikes for the best response and performance.


  • Lightweight rear derailleur.
  • Sturdy aluminum alloy construction.
  • Aluminum and composite cages.
  • Polished to endure various weather conditions.
  • Easy and smooth shifting.


  • The screws thread into plastic inserts.

5. SRAM X5 9-Speed Rear Derailleur

This is the best mountain bike 9 speed rear derailleur for flawless and precise shifting on any trail. It is compatible with 9-speed bikes and allows for fast gear shifting, thus giving you the chance to keep your eyes on the trail ahead of you.

Installing and adjusting this rear derailleur is very easy even if you haven’t done any repair work before. It is quite affordable and will allow you to save your time and effort. You don’t have to visit the bike shop for an easy repair because it doesn’t take much to mount. With light shifting, you get to enjoy more of your time on the trail because your bike moves smoothly. It is noticeably faster than other derailleurs on the market. It is an affordable yet excellent upgrade.


  • Budget-friendly derailleur.
  • Lightweight yet durable design.
  • Easy to mount and adjust.
  • Faster shifting.
  • Light shifting to save your effort.


  • The cage is thin and can bend easily.

6. SRAM GX Bicycle Rear Derailleur with 1 x 11 Speed Long Cage

This rear derailleur from SRAM provides the performance of high-end models at an affordable price. It is compatible with a number of gears available thus enabling you to shift precisely and swiftly on any trail. It is made to guarantee accurate and quick gear shifting regardless of the nature of your trail.

The offset pulleys combine with the tall square-toothed X-Sync profile to better engage and manage the chain. It eliminates ghost shifting while reducing shifting force. It is one of the best derailleurs that will save your effort no matter how challenging the trail is. It also keeps your MTB stable by maintaining consistent tension on the chain. The design allows for easy and quick installation thanks to the sealed cartridge bearings. It keeps the derailleur locked out of the way as it doesn’t interfere with the wheel for easy installation and removal.


  • Compatible with various gears available on the market.
  • Precise and swift shifting.
  • Better chain engagement.
  • Keeps the tension of the chain.
  • Reduces shifting force.


  • You need to be careful while installing it, otherwise, it can get broken.

7. Shimano Rd-tz 31 Rear Derailleur 7speed Hub Bolt Mount

This is another great product from Shimano and is designed to provide flawless and precise shifting on a road bike or MTB. It is a hub bolt mount type for easy and fast installation.

This is a rear derailleur for riders who want to have the best performance at an affordable price. Even if you are not an expert, you’ll be able to set it up in a matter of a few minutes. A kid can install this amazing derailleur easily to enjoy their ride on any trail. It is made of sturdy metal and is very durable. This is the best rear derailleur to keep your chain tensed for precise and fast shifting. It doesn’t get in the way of the wheel for the best shifting experience.


  • Durable and sturdy rear derailleur.
  • Affordable price.
  • Easy to install and set up.
  • Keeps the tension of the chain.
  • Precise and fast shifting.


  • The screws tend to scrape fast.

8. SRAM X4 8-Speed Rear Derailleur

An affordable and versatile rear derailleur is always a great bargain. This derailleur from SRAM is compatible with 7 and 8-speed bikes. It is very durable and is excellent value for the money. It is designed to provide the best performance at an affordable price.

It allows you to shift gears with minimum effort regardless of the nature of the trail. It allows for fast and precise shifting because it keeps your chain tensed. You can save your effort because your gears will shift easily while minimizing pedaling. This is an excellent derailleur to minimize the chain slap on rough terrains. Although you will have to pair it with SRAM shifters, it is worth the investment. This is a durable derailleur that will last for long.


  • Sturdy and affordable rear derailleur.
  • Keeps the chain tensed.
  • Compatible with 7 and 8-speed MTBs.
  • Allows for precise and fast shifting.
  • Minimizes the chain slap.


  • Must be used with SRAM shifters.

9. Shimano Tourney 7/8-Speed Mountain Bicycle Rear Derailleur – RD-TX800-L

The minute you see this derailleur, you will realize that there is a lot to like. It is very durable yet, it provides the performance of high-end models that cost a lot more. It comes with a smart cage that allows for better compatibility which makes it very versatile.

Double Servo-Panta Mechanism allows this derailleur to deliver the best shifting on all trails. The guide pulley tracks the cogs closely to minimize problems while shifting even at heavier loads. This is the best derailleur for optimizing your pedaling power since it shifts easily and precisely. It is very easy to install and adjust. Even if you are not an expert, you will be able to enjoy the best shifting experience. It is compatible with various mountain bikes and doesn’t cost much.


  • Affordable lightweight rear derailleur.
  • Durable and sturdy design.
  • Smart cage for better compatibility.
  • Easy to install and adjust.
  • Precise and fast shifting.


  • You need to be careful while installing it because it might bend.

10. Shimano Rear Derailleur RD-TX35

The last product on our list is another great and high-quality rear derailleur. It is affordable yet delivers the best performance on various trails. Thanks to this derailleur you will enjoy fast and effortless shifting that will allow you to enjoy your mountain biking experience to the maximum.

This derailleur shifts all gears in the best quality with little adjustment. It looks like a basic model but will provide the best performance with minimum pedaling effort. If you are looking for an affordable upgrade or a high-quality piece to repair your old bike, then you know this derailleur has got your back. It is compatible with various bikes and shifters. With a few minor adjustments, your MTB will be ready to go. It is very durable and will last for long.


  • Budget-friendly rear derailleur.
  • High-quality construction.
  • Easy to adjust.
  • Compatible with various shifters and bikes.
  • Fast and precise shifting.


  • Installing this rear derailleur is a bit difficult.

How to Choose the Best Mountain Bike Derailleurs?

Whether you are an avid mountain biker or only ride occasionally, you need to guarantee that your gears can shift easily. This guarantees that you can ride safely because you will be able to go up or down any trail with minimum effort.

There are some features that you need to pay attention to when you are shopping for the best mountain bike derailleur. You have to take them into consideration before making a purchase:

1. Compatibility

This is the first factor that you should think about while shopping for a derailleur. As a rule of thumb, you shouldn’t mix and match parts of different components or generations. You should also make sure that your derailleur is suitable for mountain bikes and not road bikes.

Most derailleurs that work for 8-speed bikes can also work for 9-speed bikes, especially if they are SRAM. These derailleurs will work for 7, 8 and 9-speed bikes easily. 10-speed derailleurs will also work with road shifters. Shimano derailleurs are not that compatible and you will have to make the extra investment to buy the appropriate shifters if they are not already installed to your MTB.

2. Weight

Most high-quality derailleurs weigh less than cheaper models. You need a good derailleur that doesn’t weigh much to allow for the best performance on the trail. Lighter derailleurs are made of aluminum or carbon. They are very durable but might be too expensive. You can always pick a model that combines steel and aluminum.

A heavy derailleur might not the best option since it can affect the speed of your bike. These are usually made of steel which is very durable but is not particularly lightweight. If the weight doesn’t bother you much, you can get away with spending less money your derailleur.

3. Longevity

More expensive derailleurs are usually made of more durable components. These are designed to last for long because they are very well made. If you tend to ride your mountain bike on a regular basis, or usually go biking on rough trails then you have to buy a heavy-duty model. Cheaper models that are made of thin metal or can bend easily are not suitable. You can always save some cash if you take mountain biking lightly.

4. Easy to Install and Adjust

How much time are you willing to spend on installing and adjusting your derailleur? It is always a good idea to buy a model that you can easily install and adjust on your own. You need to make sure that your derailleur comes with all the parts that you will need for the installment process.

5. Finish

While the finish doesn’t have much to do with the performance of the derailleur, it is still an important feature to consider. Most high-quality models look elegant, unique and will attract attention. You can spend more money to install a shiny derailleur if you want your mountain bike to stand out. The finish also protects your derailleur from the elements and ensures that it will last for long.


If it is time to upgrade your MTB, then you need to know everything about the Best Mountain Bike Derailleurs. Don’t worry if you are not that experienced with installing different bike parts. Most of the good derailleurs come with easy instalment instructions that will allow you get your MTB back on the trail. A good derailleur will allow you to shift gears flawlessly with no problems whatsoever. Make sure that you pick a good product that will work for your mountain bike and will keep your chain tensed on all terrains. These derailleurs come in all shapes and sizes and you can always find a good one regardless of your budget.

Click Here to Leave a Comment Below 0 comments