The chain is one of the essential components of a bicycle. This is where two of the three bike’s drivetrain components (the bike chain and cassette) meet to drive the bike forward. One common question by beginners when they feel like their bike drivetrains are wanting is; is my bike chain too long?
Your bike chain is too long if; when you shift to the smallest cog and chainring, the derailleur pulls the chain backward such that the chain contacts itself. Also, while on the smallest gear combination, the chain will have a lot of slack and may annoyingly keep slipping off.
How Do I Know If My Bike Chain Is Too Long?
A bike chain that is too long will be loose and will pose challenges in gear shifting. In addition, a long chain adds unnecessary mass to the bike. So how do you figure out that you have a bike that is too long?
The first method of checking whether you have a loose chain is shifting to the smallest cog and the smallest chainring. If the chain touches its self, you very likely have a chain that is too long.
Another way to check this is by measuring the distance between the center of the derailleur and the top-most portion of the chain. This should be between 1 and 2 inches, depending on your bicycle.
In addition, if you shift the chain to the largest gear in the front and the biggest cog at the rear (cross chaining), it is possible to tell whether your bike chain is too long or short.
Once you have the chain on these gears, try to push the derailleur cage forward. If the cage moves slightly, then chain length is good.
However, if the cage moves a lot, that means you have a chain that is too long, and it needs cutting.
How Do I Determine My Bike Chain Length?
There are several ways bike owners can determine the ideal chain lengths for their bikes. When replacing your bike’s chain, it is prudent to ensure that you have the precise chain length for the drivetrain’s safety.
1. Use The Old Chain As Reference
The most basic one is counting the number of links. Well, this may sound too much. However, you can use the old chain as a point of reference if it was cut to the correct size.
Ensure that the chains are lined up link to link to eliminate errors due to chain wear. Then cut the new chain equal to the number of links in the old chain.
Generally, you will need a chain tool such as the Park Tool Master link pliers (View on Amazon) to disengage master links. the tool is ideal for chains ranging from 5 to 11 speeds.
2. Try Cross Chaining
The easiest method to determine the ideal chain length is cross chaining. Cross chaining is shifting to the largest gears at the front and the rear. Remove the old chain and place the new one on the largest cog and the largest chainring with half the master link.
Pull the two ends of the chain such that they overlap each other. Find the closest link where they can be joined and give an allowance of two links. That gives you the point to cut your chain.
3. Use The Chain Equation
The third method you can use to calculate your bike’s chain length is using an equation. This method allows you to determine the size of your chain before taking the new one out of the box.
In this method, you consider the relationship between the chainstay length and the number of teeth on the largest gears.
L = 2 (C) + (F/4 + R/4 + 1)
L= Chain length to the nearest inch
C= Chainstay length. This is the distance from the center of the bottom bracket to the rear axle.
F= The number of teeth on the biggest chainring
R= The number of teeth on the largest gear on the rear cassette
Once you have determined the perfect length for your chain, cut the new one to size and replace the old one.
Does Chain Length Affect Shifting?
A properly sized bike chain makes a significant difference in gear shifting. Actually, when the chain is too long, it causes erratic shifting at the front and the rear. The chain may come off of one cog and jump to a different gear.
In addition, this could lead to the chain falling off or slipping, and as a result, it would adversely affect your riding experience.
On the other hand, when the chai is too short, the problem could be worse. First, the bike may not shift into the largest cog or ring.
At the same time, things could worsen with a tight chain because it can rip off the derailleur, damage the chain or bend the gear teeth.
So does chain length affect gear shifting in a bike? Yes, it does. Too long or too short is not suitable for your safety or the drive train.
Do I Need To Shorten My Bike Chain?
If the chain is too long, you will have to remove some links to shorten it. Mostly, if the chain rubs against the cage or itself when on the smallest cog, the most prudent action is to cut it short. However, if the chain maintains proper tension and doesn’t rub against the RD cage, you may not need to shorten it.
All the same, if you happen to replace any component of the drivetrain, such as the chainring or the cassette, with one that has fewer teeth, then you will need to shorten the bike chain.
How Do You Shorten A Bike Chain?
There are two major ways of shortening a bike chain. The two methods are similar in that you need to remove some links for the chain to be shorter.
The easiest and most professional way is using a chain cutter/riveting tool, and the other is using other unconventional tools.
How to Shorten a Bike Chain Using a Chain Cutting Tool
The easiest way of shortening a bike chain is using a chain riveting tool. A chain riveting tool is used to fasten two or more links of a chain together.
This is done by passing a rivet through the links of the chain. You force the pin up through one link to join it with the second link.
The tool has a carbide bit attached to a threaded bolt. To break the chain, you place the chain on the glove on the device with the bit on the rivet. As you screw in the bolt, the bit pushes the rivet pin out of the link on the other side.
Once one link is broken, repeat the process on the next link where you wanted to break the chain to shorten it.
Once the second link is, you link the remaining chain by pushing the pin back using the same device.
An excellent example of a bike chain riveting tool is the Chuanhuishop Universal Bicycle Chain Remover, made of steel and has a non-slip rubber handle. The device has a compact design that makes it easy to carry and easy to use. In addition, it has a strong bit that doesn’t bend or break.
How To Shorten A Bike Chain Without A Tool
On the other hand, if you don’t have a chain tool, you can hack the process using a nail, a hammer, and a pair of pliers.
All you need to do is place a link on a cone with a relatively small nail on the rivet. Hit the nail with a hammer to drive out the rivet.
Do the same to the other link you wanted to break, and your chain will be shorter. After that, join the two ends of the chain and carefully hammer back the rivet to link the chain once more.
Bike Chain Too Short Symptoms
It is possible to cut a bike chain too short. As we had mentioned earlier, an overly tight chain can be catastrophic. So what are the tell tales of a chain that is too short?
The first sign you have a bike chain that is too short for your bike is when you can’t cross-chain. If shifting to the big cog and ring is hard, then the chain is too short.
Also, if the cage is stretched almost parallel to the chainstay, you most probably have a chain that is too short for your bike.
At the same time, since the drivetrain will be under undue pressure, it will most likely produce some disturbing noise as you pedal.
Frequently Asked Questions
1. When Should I Replace My Bike Chain?
Most cyclists suggest replacing chains after five thousand miles for efficiency’s sake. Also, bulging of the links indicates that the chain is flexing too much and has been weakened by excessive wear. If this is happening, your cassette and front gears will also be showing signs of wear as a result.
When the bike chain is new, it should move effortlessly from one cog to another. If your gears are not shifting fluidly and you notice that the links of the bike chain are touching or nearly touching, it’s time to change your bicycle’s chain.
Also, it is an indication that the rest of your drivetrain components need replacement.
Once you have determined that your bike chain has reached the end of its lifespan, it’s time to find a replacement. One of the best choices is the Shimano Ultegra/XT 11-speed chain with 116 links and is ideal for both road and mountain biking.
2. Are Bike Chains Universal?
Although modern-day bike chains have a standard pitch (distance from rivet to rivet), they are not interchangeable. Each bike has a specific chain requirement depending on the number of sprockets and the length from the chainring to the cogs.
3. Do I Need A Longer Chain For A Bigger Cassette?
You will need a slightly longer chain when you replace your old cassette with a bigger one. A bigger cassette has a longer diameter which calls for a longer chain.
4. Why Does My Bike Chain Slip?
A bike chain can slip when there is too much buildup of dirt on the gears. Also, when the chain is too long or when the rear cassette is worn out, you may experience chain slips.
The chain is one of the essential components of a bicycle. If your bike chain seems too long, you need to shorten it.
It sounds simple enough, but there is a risk that the chain will lock up on itself if you shorten it improperly.
Shortening a bike chain is something that you shouldn’t do if you’re not experienced. If you can’t shorten your bike chain yourself, take it to a professional so they can do it for you.