Written by 6:08 pm MTB, MTB Maintenace

How To Adjust Your Mountain Bike Derailleur

(Last Updated On: January 22, 2021)

When it comes to mountain biking, obviously, along the way you will encounter quite a number of issues with your bike. For example, other than just having to deal with a flat tire, at times, you will find it is incredibly hard to shift gear. In other cases, you have trouble staying in gear or even the chain falling off more often. All these can be quite frustrating, but we should not want to deal with what we have mentioned, there is something you can do about it; you need to adjust your gears. If you are wondering how this can be done, here is how to adjust mountain bike gears.

The Basics

As when we are learning a few mountain bike tricks and techniques, it would make a lot of sense if we first look at the basic parts that make up your mountain bike gear. It is important you have an idea about these basic parts before you even learn how to adjust mountain bike gears:

  • Derailleur: It is a moving part. It pushes the chain from one chainring cog to the other
  • Cassette: This what house the cogs right at the back wheel
  • Chainring: It attaches the cog to the cranks
  • Limit screws: These screws play a crucial role. They actually determine how far the derailleur can move.  We normally have two of them; upper and lower.
  • B limit screw:  We use this to adjust how far below your cassette and the derailleur hangs
  • Shifter: Mechanism mounted on the handlebars. The shifter helps release the cable which is normally attached to the derailleur.
  • Inner cable: This is basically a wire. It helps connect the shifter to the derailleur
  • Outer cable: This is the cable that normally runs through the outer cable. It helps keep the inner cable tight.

How To Adjust Mountain bike Gears

Put the Bike in the stand

As when you are handling a number of issues in our bike’s drivetrain before you can have the gears adjusted, you need to put the bike in a stand. Not only will this ensure the bike is firmly fixed as you go about your business, but it will also give you great access to those parts that make up the gearing system. If you don’t have a stand, you can just have the bike resting on its handlebars.

However, you might want to be gentle so that you don’t cause any kind of damage to the handlebars or even headlight.

How To Adjust The Rear Derailleur

This shouldn’t take you hours. It is a straightforward process and you can learn it in less than 10 simple steps if you follow the steps we are going to tell you.

  • Step 1

First, before you do anything, you need to put your gear lever into a higher gear. Once you have done that keep turning the pedals. This will allow the chain to go straight onto the smallest cog on the cassette. If the gear lever body or the derailleur body does come with a cable adjuster, have it unscrewed. In this, you have to do in a clockwise direction.

  • Step 2

The second step is pretty much simple. It shouldn’t take you more than a minute to have it done. It is here that you might want to remove the cable securing bolt located on the derailleur. Once the cable has been undone, get the cable out of the way.

  • Step 3

In this stage, you are right in the middle of the whole process. Here you need to turn the pedal again. However, using your other hand, push the rear derailleur in the direction of the rear wheel. If at this point you realize the chain only travels onto the largest cog and not further, that is a good thing. It shows the derailleur inside adjusting screws are properly adjusted.

  • Step 4

Step 4 is basically a continuation of step 3. Should you find out the chain goes straight beyond the cog and eventually falls into the spokes, tune the adjusting screws on the derailleur in a clockwise direction and repeat step 3 once again. On the other hand, if the chain gets into the largest cog, but it doesn’t sit there comfortably, you have to unscrew the adjusting screws once again. But this time do it a little bit and then try again.

  • Step 5

If you are satisfied with everything, let the spring that holds the derailleur to push the derailleur outwards that is right onto the smallest cog. If at this point you experience the chain coming off or it doesn’t in any way sit comfortably in the small cog, you need to turn the other adjusting screw. That, alone, will help move the derailleur’s position.

  • Step 6

You are almost done here; if the derailleur goes properly and without any problem right between the high and low cogs on the cassette, it is time to put the whole thing back together.  Take the gear cable and refit it and finally have those securing bolts done. It is as simple as that.

  • Step 7

This is the final step and it all about testing if the whole thing now works properly. Go through every single gear a number of times. If you notice the derailleur is a little bit slow when it comes to getting into low gears, unscrew the derailleur cable adjuster.

On the other hand, if you realize it is a little bit slow when going into higher gears, you need to screw in the cable adjuster. Lastly, make sure every single bolt that secures the whole unit is tight. Thereafter you are ready for that ride.

 

How To Adjust The Front Derailleur

Adjusting the front derailleur is also simple and straightforward.

  • Step 1

The first thing you need to do it is put the gear lever is the lowest gear.  And pretty much like when you are adjusting the rears derailleur, if you find out the gear lever body does come equipped with a cable adjuster, you have to screw it all the way in. Remove the bolts that secure the operating lever of your derailleur. Once that is complete, get the cable out.

  • Step 2

In step 2, it is here when you might want to find out if your front derailleur and chainrings are parallel. Normally, there should be a gap of around 2mm between the two. If you find there are not parallel, you need to loosen the fixing clamp and make sure the derailleur is properly aligned.

  • Step 3

With the chain now sitting comfortable right in the big cog at the rear, you now need to adjust the inner adjusting screw. This will come with one primary benefit. When the chain is in the small chain ring, it will comfortably sit right in the middle of the derailleur plates.

  • Step 4

In this step, obviously the chain is now in the smaller cog right on the rear cassette. You now have to pedal the bike with your hand while the other hand pulls the front derailleur. This will make the chain go to the large chainrings at the front, and again, also right in the middle of the derailleur plate. Normally, you can pull off this by just screwing or unscrewing the outer adjusting screws normally located on the derailleur.

  • Step 5

Here, you need to allow your derailleur return to its actual position; that is over the small chainring. Also, return the cable and have it tighten and properly secured using its bolts.

  • Step 6

Here, you now need to take off the bike off the stand or off the ground. With the chain now sitting comfortably in the biggest cog right at the back, give the front derailleur a bit of a test drive. You can actually achieve this by moving the chain from the smallest right to the next chainring with the use of a gear lever. Do this a couple of times and if at some point the chain falls off the small chainring, again, just like the rear derailleur, you need to adjust the inner adjusting screws.  Here you need to ensure the derailleur does not in any way go so far in

Once you are satisfied with the test;  put the gear lever back to low gear and with the chain in the small chainrings, it is now time to loosen the cable securing bolt.

  • Step 7

You are almost done, in this step you need to put the chain right onto the small cog located on the rear cassette. If your Drivetrain comes with a 3-ring crankset, you will be forced to repeat the procedure above. However, this time you will have to do it a bit differently. It will go down the middle chainring onto the biggest chainring. Again, if the chain falls off from the front chainring, you need to adjust the outer adjusting screws. This will prevent the derailleur from moving quite so far out.

  • Step 8

You are done and this is going to be the final step. After giving the whole unit a series of test rides, if you realize your derailleur is a little bit slow when it comes to changing gears; that is from small to big chain rig, you need to unscrew a little bit the cable adjuster found on the gear lever body. Here you also need to be careful so that it does become extremely slow when it comes to changing down. Lastly, make sure all the bolts that secure the whole thing are tight. Once you are satisfied, go for those amazing test rides.

Troubleshooting Common Gearing Problems :

Chain falling off the cassette’s largest cog into spokes

The likely cause is a bent derailleur hanger. It could also mean that the low limit screws need to be correctly adjusted. Here you need to check the cassette, derailleur and the hanger. If they are not tight and some components loose, your bike will not shift properly.

The chain falling off the smallest cog and get stuck in between the frame and the cassette

A bent hanger is also the likely cause. The higher limit screws also could be needing a little bit of adjusting. You can solve this problem by ensuring the cassette, hanger, and derailleur are tight. The wheel must also be properly seated.

Shifting is slow up and down the cassette and at times you shift past a gear

It could be you have not changed your cables and housing for a really long time. Many at times the sluggish behavior of the cables and the housing could be because of debris build-up or even worn-out housing.

Final Words

Overall, it is important for you to remember that smooth and those efficient gears can bring a lot of new differences when it comes to mountain biking. It makes you enjoy your riding in almost every terrain. Adjusting your gear may seem a little bit complicated, but with the steps we have mentioned, having this part running without any problem is practically simple.

Last modified: January 22, 2021

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