Tips to Quickly Fix a Mountain Bike Chain That Is Skipping
A mountain bike chain is one of the essential components of your bike. A bike chain helps you transfer power from the pedals to the wheels and is primarily responsible for how well your bike moves. There’s nothing more annoying than having an ill-fitting chain. Not only does this affect pedaling efficiency, but if your chain constantly skips could also affect your riding performance and increase the risk of an accident during rides. However, this can be resolved by following our tips to fix mountain bike chain skipping.
Mountain bike chain skipping usually occurs due to poor maintenance, having an ill-fitted chain, or an affected derailleur. To fix a chain that’s skipping it must be adequately fitted, well maintained, and compatible with the trails being ridden.
Research from the Journal of Industrial Design and Mechanical Engineering highlights how bike performance mainly depends on the chain drive system.
A significant reason for mountain bike chain skipping is when it is incompatible with your bike and riding trails. For instance, the chains on road bikes are designed to help riders shift down and traverse high-speed trails and flat terrains. On the other hand, mountain bike chains are tailored to handle heavier loads and shift up on mountainous landscapes. It is therefore vital to understand your bike type and riding terrain. Check out our article that looks at the difference between mountain bike vs. road bike chains for tips and tricks on selecting the right one.
Why Does My Mountain Bike Chain Skip?
Being one of the most kinetic parts of the bike, it’s not uncommon for you to encounter bike chain issues with significant use.
Mountain bike chains can skip if they are not adequately maintained, aren’t suited for the type of bike, or if the bike derailleur needs repair.
This article by the Science of Cycling emphasizes how the bike chain is one of the major factors responsible for making bikes the most energy-efficient mode of human transport. This is because the mountain bike chain is responsible for transferring power from the pedals to the rear wheel and is therefore the primary component that makes the bike move. That being said, an affected or skipping bike chain that moves out of its intended position, would invariably hamper your riding performance and is more likely to put you and your bike in harm’s way.
It’s essential to know when your bike chain is affected or skipping in the first place, to fix it. A tell-tale sign of a skipping bike chain is when you hear rattling or creaking noises in the chain area. Additionally, if you notice your pedals suddenly lose power during rides or your bike slows down or comes to a complete halt, then you're most likely dealing with a skipping bike chain.
Now that you know how to tell if your bike chain is skipping, here are a few reasons why it might be happening:
Reason 1. Having an Ill-Fitting Bike Chain
Bike chains like these come in different lengths, shapes, and sizes and are each crafted for various bikes, trails, and riding needs. Understanding the fundamental factors that govern bike chains would go a long way in helping you make informed decisions when choosing new chains or adjusting an old one.
A chain that is too long is more likely to skip or jump between the bike gears. Conversely, a short chain would be a hassle to fit around your gears and is more likely to snap while riding, so getting an adequately-tailored bike chain is pertinent.
Similarly, you might find interest in learning what to do if your mountain bike handlebar keeps twisting. If so, be sure to read our related article for more information.
Reason 2. A Worn Out or Damaged Bike Chain
Overtime and after covering a significant distance, bike chains get loose or worn out. Worn-out bike chains won’t correctly accommodate the teeth of cogs like these. The more you ride, particularly on rough terrains or uphill, the more likely the chain is to slip off the cassette, leading to skipping. Additionally, if any parts of the chain ring are damaged, particularly the chainrings or cassette, it’ll be much more difficult for your bike chain to stay in place as it’s more likely to skip. Our tips for quick and proper mountain bike chain maintenance explain the best methods to manage your chain to prolong its useful lifespan.
Reason 3. A Loose Bike Shifting Cable
Shifting cables are more likely to stretch out with time and consistent use. A stretched-out cable does a poor job at holding the bike chain in place and could be another reason your bike chain is skipping during rides. You may solve this issue by tightening your stretched-out bike cable or replacing it with a new one like this if it cannot be fixed.
Reason 4. Affected Chain
A compromise of any of the intrinsic parts of the bike chain would jeopardize its overall functioning. Furthermore, components like the derailleur, cable, and pedals are near the bike chain and usually function as a unit to make riding possible. It is therefore important to routinely inspect the different components of your chain and drivetrain like this to avoid unwanted mechanical issues.
Reason 5. Neglecting to Do Proper Bike Chain Maintenance
Since bike chains are under significant kinetic stress, they are more likely to rust, wear out, or get damaged with time. Furthermore, since they are the major propellers of the bike wheel and connect the pedals to the rear wheel, different parts of the chain are likely to have a buildup of dirt and grime. These particles can cause friction along the length of the chain and constrict the flow of movement which is why it is so important to perform quick and proper mountain bike chain maintenance, as explained in our article, which includes cleaning with a kit like this.
Reason 6. An Altered Derailleur
A bike chain connects the front and the rear derailleur. This connection allows riders to modulate pedaling effort and generate maximum output during rides. The bike chain is wrapped around this device and is the primary driving force of this mechanism’s functioning. Since both the bike chain and derailleur function together, the damage to one could lead to the compromise of the other.
The rear derailleur like this one is more commonly affected than the front one. Due to its thinner, lighter frame, it’s more likely to get bent or broken on impact. Damage to any part of the derailleurs would affect its ability to guide or hold the bike chain correctly, leading to bike chain skipping.
When adjusted to a new position, derailleurs are set to line up with the selected chain ring and guide the length of the bike chain into the latest gear. However, if either of the derailleurs isn’t adjusted correctly, there’s a higher chance of the bike chain skipping during rides.
Common Symptoms of Mountain Bike Chain Skipping
Usually, a skipping bike chain is undetectable when it first starts and usually takes an extended period and damage, before riders notice anything is wrong. So it’s vital to carry out routine checks on your bike’s chain, so you’re better able to manage the situation before it develops into something much worse.
Common mountain bike chain skipping problems are a noisy chain, reduced pedaling power, inefficient gear changes, and other damaged bike parts.
As mentioned earlier, the primary way to know when your bike chain is skipping is when you start hearing unpleasant frictional noises in the chain area or if you notice a sudden decline in your pedaling power.
According to this article by whptv.org, a worn-out cog or chain could affect pedaling efficiency and, invariably, riding performance. As mentioned earlier, bike chains are the primary component responsible for propelling the bike. These chains are connected to enhance kinetic power and improve riding ability. If any of the intrinsic elements of the bike chain is damaged or worn out, the kinetic transfer from the pedals to the bike wheels through the bike chain would be affected.
Here are a few common symptoms of why a mountain bike chain skips, why they happen, and quick tips to fix them:
Symptom 1. Mountain Bike Chain Skipping While Pedaling
Pedaling is one of the primary ways to detect that your bike chain is skipping. Bike chains are responsible for transferring power to the bike wheels when pedaling movement is initiated. However, several factors could lead to the bike chain skipping during this action.
The first could be poorly fitted pedals with a loose grip which could be replaced with pedals like these. Ill-fitted pedals affect the transferring power of the bike chain and increases the likelihood of the bike chain skipping during rides. Our article on choosing bike pedals for grip maximization will be helpful in making the necessary changes.
Another reason why your bike chain keeps skipping during pedaling is improper bike chain length. If your bike chain is longer than your chainrings require or any component of the bike chain is damaged or improperly maintained, there’s a greater chance of your bike chain skipping during rides. If you find your bike chain skipping while pedaling, you might need to adjust your front or rear derailleur.
Symptom 2. Mountain Bike Chain Skipping Under Load
When your bike chain skips under pedaling load, this is called ghost skipping. The greater the distance and rougher the trails you ride, the more necessary it is for your bike chain to shift gears. However, if you have an ill-fitting chain, the pressure transferred from your pedaling might be unequal, and the bike chain compensates by skipping or jumping gears with increased pedaling intensity.
Symptom 3. New Mountain Bike Chain Slipping
As highlighted earlier, a bike chain, much longer than your chainrings require, is more likely to jump between gears. Hence, it is vital to ensure you choose a bike chain that’s just the right length for your bike and riding needs. The best way to compare the size of the new chain is with the old chain as we explain in our symptoms and fixes for if your mountain bike chain is too long. That is if your old chain was efficient while in use.
However, since bike chains tend to stretch out after use for a long time, a more precise method of determining your bike chain length is called the “big-big method”. This method involves you sizing your chain by putting it around the biggest chainring in front and the biggest sprocket in the back without placing it through the rear derailleur. After which, you’d leave about an inch or one link for the derailleur and tension the chain until it fits correctly. After finding the proper bike chain like this, it’s advisable to make sure you set it up correctly to avoid damage. Our article about mountain bike chain installation explains selecting and installing the suitable chain for your bike.
Symptom 4. Bike Chain Slipping in Higher Gears
If you find your mountain bike chain skipping or slipping in higher gears, it’s most likely due to a worn or defective gear set. In this case, you might need to adjust the bike chain length and lubricate the chain. After making the adjustments, ensure the bike chain is tensioned evenly along the chainrings. And finally, make sure it is adequately positioned using a chain guide like this to make sure it doesn't rub against the bike wheels or frame.
Tools Needed To Fix a Skipping Bike Chain
Now that you know what causes a skipping bike chain and why it happens, it’s time to look at how to fix the problem.
Tools needed to fix a mountain bike chain that’s skipping are a screwdriver, brush or cloth, degreaser, chain lubricant, chain measuring tool, gloves, and possibly a chain breaker.
As outlined in this article, the first way to repair your bike chain is by knowing what is causing the situation in the first place. Be it an improper length, worn-out intrinsic components, or affected chain area, knowing the specific reason why your bike chain skips would save you a lot of stress and guesswork when fixing the issue.
Make sure that you have the following tools handy to make repairing your mountain bike chain easier:
Tool 1. Screwdriver
If your mountain bike chain is skipping due to a derailleur issue, a screwdriver from a set like this will come in handy when adjusting the area. We recommend considering a fine-tip screwdriver that can tighten or loosen the derailleur screws as needed.
Tool 2. Brush or Cloth
Since mountain bike chains involve many kinetic movements, there’s a high chance of your chain having a dirt and grime build-up. The gunk can cloud the visibility of the length of the chain and may blur your diagnosis of the skipping issue. Have a well-bristled brush from a set like this or a microfiber cloth to wipe away the gunk.
Tool 3. Degreaser
As mentioned above, bike chains are likely to build up with grime when used for more extended periods. The build-up might be several layers thick and challenging to clean off with just a cloth. A degreaser like this is a chemical that helps melt away the said build-up, making cleaning the bike chain a lot less of a hassle.
Tool 4. Gloves
Bike chain maintenance can be a bit of a messy job. If you’re one who doesn’t particularly like getting your hands dirty, it is in your best interest to put on a pair of rubber gloves like this prior to starting the procedure.
Tool 5. Chain Lubricant
One of the common reasons why your bike chain is skipping could be increased friction within the bike chain components or between the bike chain and the chainrings. A chain lubricant like this would help lube the necessary parts and restore needed function. Our ultimate list of mountain bike chain lube alternatives could be a handy resource for you.
Tool 6. Chain Measuring Tool
A chain measuring tool like a ruler or a pair of calipers like this would help you adequately assess the length of your bike chain. Regularly measuring your chain would be an excellent way to keep track of the measurements that are most compatible with your chainrings and equip you to take quick action when your chain starts showing wear.
Tool 7. Chain Breaker
If your bike chain is beyond salvaging, or you experience difficulty adjusting inflexible areas or replacing worn-out bike parts, a chain tool from a set like this would give you a much-needed break - no pun intended.
Summary of Tools Needed to Repair a Skipping Mountain Bike Chain
| Tool | Why You Need It | Amazon Example |
| Screwdriver | To adjust derailleur | Vibrelli Bike Multi-Tool |
| Brush or rag | To clean grime buildup | Oumers Bike Cleaning Set |
| Degreaser | To dissolved caked grease and dirt buildup | WD-40 Bike Chain Lube |
| Chain lubricant | To lube friction-prone areas | Finish Line Wet Bike Lubricant Finish Line Dry Bike Lubricant |
| Gloves | To protect your hands during maintenance | Disposable black nitrile gloves |
| Chain measuring tool | To measure the length of the bike chain | TuoTu Bicycle Chain Checker |
| Chain breaker kit | To split and repair the mountain bike chain | Bike chain kit |
You might also find interest in learning the differences between road versus mountain bike saddles. Be sure to read our related article to find out more.
How To Fix a Skipping Bike Chain
Dealing with bike chain issues while riding is both unpleasant and dangerous. Now that you’re clear on the whats and whys of bike chain skipping, we will walk you through the hows of fixing a skipping bike chain.
To fix a skipping mountain bike chain, stabilize the bike, clean the bike chain, inspect the bike chain area, adjust the cable tension, check for derailleur damage, inspect the rear cassette and chainrings, and lubricate the bike chain.
After you’ve gotten the necessary tools, and identified the cause of the bike chain skipping, it’s time to get to work. Here’s the step-by-step guide on how to fix a skipping bike chain:
Step 1. Stabilize The Bike
The first step to follow in fixing a bike chain that keeps skipping is first to stabilize your bike. You want to set your bike so that you can access the bike pedals, as this would make your work faster and more efficient. If you have a bike repair stand like this, set your bike on it. Alternatively, you could flip it upside down and prop it on the saddle and handlebars.
Step 2. Clean The Bike Chain
After propping your bike comfortably, the chain area can be cleaned. Start by wiping off the bike chain, cogs, and derailleurs with a cloth. Next, apply some degreaser on areas with grime build-up. And finally, scrub off the degreased areas with a brush, a fine-bristled toothbrush would do, to remove the accumulated gunk.
Step 3. Inspect The Chain And Chain Area
Check the parts of the drivetrain and chain area to determine the cause of the bike chain skipping. If your bike chain is too long, removing links from the chain until you reach an ideal length, is advisable. Our article on tips for choosing the number of links in a mountain bike chain would serve as a helpful guide on how to adjust your bike chain length.
Step 4. Adjust the Cable Tension
After an extended period of use, bike cables tend to get loose. A loose bike cable wouldn’t be able to properly hold the bike chain in place, which could lead to bike chain skipping. Adjust the cable tension by altering the barrel adjusters on your shifters. If it takes several pedaling revolutions to complete a shift, i.e. the shifting is slow, you need to tighten the cable. On the other hand, if the bike chain skips multiple gears at a time or shifts spontaneously without activating the shifters, you would need to loosen the cable.
Step 5. Check For Derailleur Damage
When setting the rear derailleur, it’s vital to ensure the selected chain ring, derailleurs, and derailleur pulleys line up correctly. If you were to eliminate the space between these parts and they don’t fall in a straight line, there’s most likely a problem somewhere. The likely cause could be a bent derailleur hanger which leaves the derailleur pulleys angled out of line. Luckily derailleur hangers like these are pretty affordable and easy to replace. However, supposing you realize there’s nothing particularly wrong with the hangers and notice the issue is with the derailleur itself, then rather than bending it back, it’s best to replace the derailleurs altogether. Replacing a derailleur with something like this is pricier but is better in the long run.
On the other hand, unlike the rear derailleur, which is more likely to get bent, a front derailleur is usually affected due to improper alignment within the frame. You may adjust this issue by altering the angle of the derailleur. To change the derailleur angle, loosen the bolt that attaches the derailleur to the bike frame with a screwdriver. Set the angle of the derailleur until both sides are parallel to the bike chain. And finally, tighten the bolt when you attain the desired slope.
Step 6. Inspect the Rear Cassette and Chainrings
The chain area is the region primarily responsible for your bike kinematics, so ensuring that all aspects of this area are in perfect condition is vital. Inspect the chainrings for breaks, rust, or any damage.
However, if the asymmetry appears to occur for most of the length of the chain or skipping persists even after replacing defective areas, it’s in your best interest to replace the entire chainring or cassette as a whole with one like this.
Step 7. Lubricate the Bike Chain
Since bike chains are responsible for transferring the power from the pedals to the wheels, there’s a lot of rubbing. This frequent rubbing of parts would increase wear and tear in the concerned areas and increase friction within the chain mechanism. If you notice significant friction when rotating your pedals, your bike chain is due for greasing.
Since bike trails vary and weather plays a significant part in that variability, you need to ensure you’re getting a lubricant that best suits your bike and current riding situation. An option like this would be favorable during wet seasons, while an oil like this would be a better choice for dryer terrains. Once you’ve found the ideal lubricant for your bike, squeeze the fluid along the areas that are experiencing friction. Avoid running lubricant over the brake area, as this could limit the braking ability.
