How To Tighten Chainring Bolts

When looking for the best types of bicycles in the market, there are many things to put into consideration. However, you won’t get it wrong if you go for a bike with a standout chainset or crankset. It is one of the key parts of a bike drivetrain that make it easy to drive the chain and turn the wheel.

The crankset is made up of several chainrings that make a big difference when it comes to the effectiveness of your bike. Chainrings are a vital cog in your bicycle and help transfer power a rider creates by turning the chain round to the rear wheel. The type of chainrings your bike comes with matters a lot.

They come in varying sizes that fit different types of cycling. That’s why you have to decide whether to pick a road, mountain, or BMX bike. Road bikes feature a double chainset, which means they have two chainrings. The large chainrings will give you bigger and hard-to-turn gears to move your pedals at higher speeds. If you are using smaller chainrings, they will give your gears an easier pedal turn to drive at lower speeds.

Many bike riders fancy the benefits of having an efficient chainring, but understanding how chainring bolts work is paramount. Unfortunately, many people ignore these bolts until a problem arises. They cannot pedal their bikes efficiently from one point to another.

Everything To Know About Chainring Bolts

Bottom brackets in most bicycles are hollow to allow chainring bolts to thread into the ends and hold the crankset in place. Bolts are the threaded fasteners with an external male thread that has to be matched with an existing female thread- the nut. Chainring bolts are reliable fasteners and play an incredible role in your bike.

Most bikes have between three to six bolts attached to the crank. These bolts are all spaced between the bolt’s circle and should be in good condition all the time. Many bike owners wonder whether chainring bolts are universally accepted.

The good news is that the female-threaded part of the bolt features a standard external diameter of 10mm and will fit into any chainset. However, this doesn’t mean that any set of chainring bolts will work perfectly for every chainset. As a rule of thumb, a set of chainset bolts designed for use with a single chainring will do the job excellently.

The good thing about chainring bolts is that they are easy to use. You can simply install and uninstall your crank bolts. Also, you don’t have to use heat treatment to remove or tighten chainring bolts.

It’s easy to remove bolts using hands despite specific tools designed to tighten and remove them. With this in mind, it’s wise to answer the question, what size are chainring bolts? Chainring bolts come in varying sizes, and you should get types that suit your crankset.

Whether you are replacing an old bolt or swapping it with a new one, get the correct bolt size. Significantly, consider the size of chainring bolts if you are planning to add a chainring spacer to enhance your bike’s chain line. And if you have lost one of your chainring bolts, you will also need to put its size into consideration.

Chainring bolts come in lengths as long as 6mm to 16mm. Some bolts thread directly into the spider, while others will need extra nuts attached into place. Don’t forget the size of the chainring bolt’s hex socket as you measure the size of your bolts.

Many riders may not know that the larger the hex socket, the easier it is to install and remove without worries of shedding. The color of your chainring bolt is imperative as it adds some pop to your drivetrain. You can imagine the joy of having gold chainring bolts on your road or mountain bike. It’s indeed fantastic and pleasing to the eyes.

Standard chainring bolt and nut pairs come in the classic double size and configuration. They perfectly work on mountain and road bikes when two rings have attached to either side of the crankset. There is a lot of clamping involved when dealing with bolts.

The inner part needs to be long enough to obtain sufficient tightening force. It’s wise to mind the total thickness of a chainring bolt as you don’t want it to clamp before you tighten it onto the chainrings. As you figure out what size are chainring bolts, feel free to measure the bolt circle diameter (BCD)

BCD is the ideal circle that passes through the centers of all bolts, more so, the standard chainring bolts used in bikes. It’s easy to measure 4-bolt cranks but quite daunting to measure 5-bolt cranks used in road bikes. BCD also defines the position of chainring bolts diametrically.

The size of the bolt mounting must match the chainrings and cranks, or they won’t tighten up at all. It’s easy to measure the length of 4 bolt cranks found in mountain bikes by measuring directly across the diameter. While in the case of 5 bolt cranks found in road bikes, it can be a taxing procedure.

Reusing Chainring Bolts

Many questions arise when figuring out what size and types of bolts and nuts to use in a bike. Many cyclists wonder whether one can reuse chainring bolts. Mechanically, it’s wise and advisable to reuse chainring bolts on the condition that the bolts have not exceeded their yielding points.

When a chainring bolt is working correctly and in its proof scale, you can still use it in your bikes. The bolt should return to its original shape upon removal depending on the application, the grade, and recommendation by “Engineer of Record.”

Other factors that help determine whether one can reuse chainring bolts are the application method and finish. When bolts have been tensioned beyond the yield point, they tend to elongate and are exposed to premature failure. If you fail to replace your damaged bolts, you will end up spending a lot of money, and your bicycle won’t work.

You can reuse your chainring bolts if:

  • There is no detectable damage or corrosion on the surface of the bolts.
  • They look clean and new than the ones you have been using.

In most cases, chainring bolts are made of different materials, but steel or titanium bolts stand out and can last longer. Hence, you can reuse them more occasionally than aluminum bolts. They are known to handle torque better than aluminum bolts that are lightweight and come in varying colors.

When reusing crank bolts, always clean them to perfection. You will ensure no grit or dirt may deter proper tightening or removal of the bolt.

Tightening and Removing Chainring Bolts-What to Know

It may seem quite easy to remove or tighten chainring bolts and nuts. It can seem a straightforward task to undertake for many people who have tightened bolts before. However, the entire process is not that easy, and you should be cautious when tightening or removing bolts.

One question that wanders in many people’s minds is, how tight should chainring bolts be? In general, you should ensure the chainring bolt is tight enough and ensure the parts it’s holding together stay intact. Yet the bolt shouldn’t be too tight that you damage its threads.
At all times, you should tighten your bolts properly so that they perform their roles properly. If stuck, ask yourself how to tighten chainring bolts without tools. Indeed, there are several methods of tightening chainring bolts you can utilize.

You can tighten chainring bolts with single finger tightness, especially if your bolts are adequately greased and not damaged. You can also stiffen your bolts for optimum performance using a few techniques. They include:

Using Wrench

You don’t have to stress about how to tighten Shimano chainring bolts if you are well-acquainted with using a wrench. It’s one of the standard tools used to stiffen bolts in a bike crankset. With a simple twist, you can fasten your bolts until it just feels right to you.
You have to be cautious when using a wrench as you never know how the final bolt tension load will be or the torque. The wrench itself can easily damage the chainring bolt body. It can cause damage and lead to the failure of your bolts.

Torque Level

You will get the best results if you tighten your chainring bolts to a specific level of torque. The correct torque level is imperative for road or mountain bikes because you have to mind your safety. When you tighten your bolts properly, the stem of the chainring bolt will sustain some direct stress.

This effect can be attributed to the torque level acting on the threads, and it causes the bolt top to stretch a bit. If you feel the chainring bolt will loosen over time due to vibration, use a prevailing torque fastener. You will have an incredible way to achieve optimum torque level in place instead of over-tightening the bolts.

The other method you can rely on and figure out how to tighten Shimano chainring bolts includes electronic systems. These systems have control systems sensitive to the torque levels of the Shimano bolts being tightened. They have sensors that know when to stop tightening the bolt.

As you learn how to tighten Ultegra chainring bolts, keep a number of things that make these bolts loosened.

They include:

  • Under-tightening leads to sideways slippage between joints and places unwanted tension on the crank.
  • Any vibration causes the bolts or nuts to move parallel with each other.
  • Mechanical shock applied to the bolt thread leading to loosening of the bolts.
  • Thermal expansion due to rapid environmental changes when cycling.

When tightening your chainring bolts, you can avert loosening by using washers, applying grease on bolt threads, or using double nuts.
When it comes to removing chainring bolts, you should be cautious in your undertakings also. Don’t just assume it’s a matter of using the available tool, and you are good to go. It’s wise also to figure out how to remove chainring bolts without a tool.

If your bolts are not too snug onto the crankset, you can use your bare hands to loosen them. Applying grease will also make sure the bolt threads don’t stress from the tension applied when tightening.

You should remove and replace your chainring bolts if:

  • The bolts are damaged on the thread or wrench locations.
  • There is excessive torque necessary to loosen the bolts.
  • Corrosion or any related problem is visible on the bolts.
  • The bolt feels scratchy when you are tightening it.
  • The chainring bolt is too short or too long for the application at hand.
  • When moving from a double chainring to a single font type.

Now, you can go on and figure out how you remove Shimano chainring bolts?

Here are steps to follow:

  • Essential tools you will need include a hex key, Torx key set, and chainring nut wrench tool
  • Let the wrench sit on the tightened bolt and hold the rear nut with the hex key to prevent it from turning.
  • Secure the nut in an anti-clockwise direction.
  • Loosen and then unscrew the chainring bolt.
  • Remove the bolts, and ensure they are in a safe place for later use.
  • Go on and remove the chainring to clean it.

Final Thought

It should be that taxing to tighten and remove chainring bolts. You have to gather the right tools for the task ahead. The process shouldn’t take long if the bolts are in good shape and not damaged. Be cautious enough not to damage the bolt threads. You will do the entire task in a few minutes and undertake the necessary crankset, replacement, repair, and maintenance.

Jonathan Tim
Jonathan Tim
A bicycle geek since early childhood spent his twenties as a mechanic in bike shops. His passions include flatland BMX, unicycles, cycle touring, mountain biking, and road riding.