Chainrings play a vital role in the setup of your bike. Whether single, double, or triple chainrings, they have their uses and are suitable for different terrains. Chainrings come in different sizes that are used for different purposes on diverse bikes.
Not all of these sizes will come with your bike, but that doesn’t mean you can’t change your chainring to a different size of your choice.
In this article, we’ll be discussing the possibilities of changing your chainring size, the why you need bigger or smaller chainrings and guide you into deciding on the one that is best suited to your needs.
Can I Change the Chainring Size?
Yes, you can change the chainring size for your bike depending upon various factors such as climbing needs, cadence, carrying weight, etc., and it is quite possible to do irrespective of the bike you may be using.
Whether you want to change from a smaller chainring to a bigger one or vice versa, it can be done without problems. You just have to consider a few factors and put a few things in place. The new chainring has to work with your current setup.
Things to Consider While Changing Chainring Size
1- Number of Bolts
Chainrings usually use between 4 and 5 bolts.
Before buying a new chainring with a different size for your bike, first, note the number of bolt holes that are on the former one. The new chainring must have the exact number of bolt holes for it to be able to work with your crankset.
It doesn’t matter if you’re changing to a smaller or bigger chainring, as long as you stick to the same number of bolts, you’ll have less difficulty in fixing it.
2- Bolt Circle Diameter
It is the diameter of the circle that passes through the center of your bolt and it is measured in millimeters. It is usually written on the chainring but if it’s not, you would have to measure it so you can buy one with the same measurement.
The bolt circle diameter of your former chainring must match the new one you’re about to buy and install.
3- Front Derailleur
If you’re changing the chainring size on your bike, then you will need to adjust your front derailleur to accommodate this change.
If you’re changing to a bigger size then your front derailleur will have to be shifted up to accommodate it and if you’re changing to a smaller one, your front derailleur will be shifted down a bit.
Some front derailleurs are not built to be adjusted like that so you may have to buy one that matches your new size chainring.
If it’s multiple chainrings, you may need to increase or decrease the other rings too as the case may be.
Some derailleurs cannot work with multiple chainrings with a big difference in sizes. Your chain may also need to be increased or decreased.
SMALLER CHAINRINGS
When Would You Use a Small Chainring?
Shifting to a small chainring or adding one to your bike can be the difference between a rough ride and a smooth one.
1- CLIMBING
You should use a small chainring when you want to climb because it’s easier. Climbing with large chainrings is difficult and tiring you may end up carrying your bike and walking.
Combining your cogs with a small chainring gives you easy gear that is necessary for hill climbing and steep terrains. It also makes longer rides less tiring.
2- CARRYING WEIGHT
You should also use a small chainring If you’re going to be carrying lots of loads.
Because of the easy gear, it gives, carrying extra weight on your bike is very easy with a small chainring.
It requires less of your energy compared to a bigger chainring, so you can ride longer without getting tired.
3- HIGH CADENCE
Cadence is the number of times you turn your pedals per minute. You should use a small chainring if you want to gain and maintain a high cadence.
To turn your pedals faster, quicker and more efficiently, you need to use a small chainring. Maintaining a high cadence is also necessary if you want to climb more efficiently.
Can I Put a Smaller Chainring on My Road Bike?
Yes, you can. This will make it suitable for diverse terrains and make pedaling easier.
Putting a smaller chainring on your road bike isn’t a problem but you may have to change your crankset.
Most road bikes come with double chainrings and can either be standard or a compact.
Standard Chainrings
Standard chainrings usually come in 53/39t. This means the larger chainring has 53 teeth and the smaller one has 39 teeth.
If you use a standard crankset, you would have to change to compact to get a smaller chainring. A compact crankset uses a 50/34t and this would give you easier gears to climb faster.
To put a smaller chainring than 34t on your road bike though, you would have to switch from double to triple crankset entirely.
You can’t get lesser than a 34t on a compact crankset but with a triple crankset, you can get as low as 28t.
Touring triples come in 48/38/28 but fixing this on your bike requires changing a few components.
Your front derailleur will need to be changed, your rear wheel also needs a rear derailleur with a long cage and you may also need to change your shifters.
Can I Put a Smaller Chainring on My Mtb?
Yes, you can. In the mountain bike world recently, single chainrings are fast gaining popularity as cassettes now come in bigger sizes.
It is less difficult to change them, so putting smaller chainrings on your mountain bike is quite feasible.
They come in different sizes and types. So whether it’s a bolt-type or mount type you want, you can always get a smaller one and fix it on your bike. And since they don’t use front derailleurs, you don’t have to worry about adjustments and compatibility.
You can as well put smaller chainrings on your mountain bike if you use double chainrings. You have to make sure the new chainring you’re fixing is compatible with your cassette speed though.
You can get a double chainring that has as low as 30T on the smaller chainring. To go lower than this, however, you would have to get a direct mount chainring.
Triple chainrings aren’t that popular among mountain bikers anymore but they are still very much in use. If you use one, you have more chance of getting smaller chainrings. You can get a granny gear of 22T. It would be a chainring of 44/32/22 which would give you very easy gears and be suitable for different types of rides.
BIGGER CHAINRINGS
When Would You Use a Bigger Chainring?
You should shift to a bigger chainring or put one on your bike if:
1- YOU WANT TO GO FASTER
Combining a large chainring with your smallest sprocket will give you high gear, which will make you go faster on flat terrain.
This is essential if you are using small-wheeled bikes.
Using bigger chainrings on small-wheeled bikes enables you to move at the same speed as other bikes.
2- YOU WANT TO DESCEND
You should use a bigger chainring if you want to go downhill on your bike.
This hard gear makes it difficult to pedal but you will accelerate downhill at a faster pace and the descent will be more fun than intimidating.
Can I Put a Bigger Chainring on My Road Bike?
Yes, you can. Road bikes are quite adaptable and you can put bigger chainrings on them without encountering problems or damaging them.
You should however bear a few things in mind.
A- If you’re putting a bigger chainring on your road bike because you want a wider range of gears, you should add a smaller sprocket to your cassette instead of a bigger chainring.
For example, if you’re using a compact chainring which is 50/34T and a rear cassette with 12 as the smallest sprocket, getting a 53 or 54T chainring won’t make you go faster or give you higher gears. But getting a smaller sprocket of say 10 will help you achieve this. 50/11 is still a bigger gear than 54/12.
B- When putting a bigger chainring on your road bike, you should also avoid too much of a difference between the outer and inner rings.
For example, if you’re using a compact 50/34 and you want to increase your outer ring to 54, you should increase your inner ring too. This is because having more than a 16T difference between your outer and inner ring will affect your shifting. Your chain will also drop often. You can however install a chain catcher to avoid this.
Instead of increasing the size of both the outer chainring and the inner chainring, you can also swap your compact chainring to a standard one which will come with bigger chainring sizes. However, this will be more expensive.
Can I Put a Bigger Chainring on My Mtb?
Yes, you can put a bigger chainring on your Mtb. As long as you adjust the necessary components to accommodate the new chainring, it will work fine.
Just like for the road bike, you also have to ensure there isn’t too much of a difference between the rings. The size of the new chainring also has to be compatible with the speed of your bike.
Sometimes, to get a bigger chainring, you may need to change your chainset.
For example, if you’re using a triple chainring of 42/34/24T, you could change it to a 48/36/22T or 48/38/24T. If you want a bigger chainring you can even go as high as 52/38/24 as long as your bike speed can accommodate it and is still within your BCD.
Smaller vs. Bigger Chainrings
Here is a quick comparison of the two chainrings:
| Smaller Chainring | Bigger Chainring |
| Suitable for climbing. | Not suitable for climbing. |
| Drivetrain wears out faster. | Drivetrain lasts longer. |
| Suitable for long rides. | Not suitable for long rides. |
| Chain drops easily. | Less chances of chain dropping off. |
| Cannot go very fast. | Aids speed, especially on flat terrains. |
| Not suitable for descents. | Suitable for descending fast. |
Final Thoughts!
You can always change your chainring size to suit your needs and preferences. Bigger chainrings have their advantages and suit different purposes and situations different from that of smaller chainrings.
Just make sure your bike can adapt to the changes and your other bike components can be adjusted to work with it.
The downside of bigger chainrings is weight. They are heavier and will increase the weight of your bike which will take some time for you to get used to. They however cause less wear to your drivetrain because the weight of your bike will be distributed over more teeth.
Choosing a bigger or smaller ring should be more than a fashion statement and we have explained in detail what each is used for so you can decide which one suits your need.
Cheers!
