Can you put a longer bar on a chainsaw? What does narrow kerf mean and what is a sprocket nose? These are just a few of the questions I’ve come across during my research and in this article I will answer these and other questions.

So let’s dive straight in.


What size bars can you get?

They come in a variety of sizes. Typically, most homeowner saws have bars which measure between 10 inches and 20 inches in length, although something like the Husqvarna Rancher 460 can take a 24-inch bar.

As you would expect, professional saws are capable of handling even bigger units than this. The Stihl MS 880 Magnum, for example, will handle a 59” bar. That’s just under 5 feet of cutting power and something you probably won't need around the yard!

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What are they made of?

Modern guide bars are constructed from a variety of strong and lightweight materials.

These include aluminum, a low density and therefore very light material, which has excellent strength and malleability. As well as this it also has good resistance to corrosion.

Chrome-moly steel (Abbreviation of Chrome-molybdenum) is also used to manufacture many of today’s modern units. It is not as lightweight as aluminum alloys, but has the advantages of high tensile strength and malleability.

What is a sprocket nose bar?

There are basically two types – those with sprockets (called sprocket nose bars) and those without (generally referred to as hard-nosed).

For those non-technically minded folks out there, a sprocket is simply a wheel with teeth which is designed to engage with something (in this case the chain) that will be pulled over the wheel as it rotates. On a chainsaw, the sprocket is at the tip of the bar (hence the term nose sprocket) and is designed to reduce friction and therefore increase cutting performance.

A hard nose does not have any wheel at its tip, and these are usually favored when working in gritty, difficult conditions and when cutting dirty wood which might jam the sprocket.

On chainsaws, the number of teeth on the sprocket varies and those with up to 10 teeth tend to have low kickback qualities. Models with 11 teeth or more have a higher kickback tendency but better cutting performance, though these tend not to be found on homeowner saws.


Most homeowner saws have sprocket nose guide bars and whilst these offer better cutting performance, they do need a little more maintenance. You will need to ensure that the nose is greased regularly to prevent the sprocket from seizing up. This is done by injecting grease into the nose hole with a grease gun (as shown below). These can be picked up for around $6.

What is a narrow-kerf bar?

The kerf refers to the width of the bar and therefore the type of chain it can carry. As the name implies, a narrow kerf means it has a smaller width than the standard kerf unit. As the saw cuts, it creates a channel or groove and this is the kerf. The narrow kerf bar removes less material than the standard kerf, thereby creating a narrower groove.

Narrow kerfs are more suited to light and medium duty cutting and are popular on home owner saws. They perform less well on larger, more demanding cuts. If you had a 30 inch diameter oak tree to take down you certainly wouldn’t opt for the narrow kerf bar and chain.

Can you put a longer bar on a chainsaw?

The answer is yes and no.

Chainsaws need to have sufficient power to handle certain length bars. The bottom line is that without this the saw will be underpowered and won’t cut properly. Some common power to size bars are:

Power Size

Bar Size (Inches)

Gas:            32cc – 42cc


Gas:            45cc – 50cc


Gas:            51cc - 60cc


Electric:      8-10 Amps


Electric:      12-15 Amps


Battery:       18-24 Volt


Battery:       36-40 Volt


Battery:       56-80 Volt


Many chainsaws are designed to take different size units. For example, the Husqvarna 460 Rancher is commonly sold with a 20 inch bar and chain. However, it is capable of taking anything between 13” and 24”. In this case, it’s unlikely you would buy anything as powerful as 60cc a Rancher and put a 13 inch blade on it, but the flexibility is available.

Other saws are sold with certain cutting components and don’t allow for different sizes to be fitted. The advice is always to check the individual model. You can check our reviews, which include a section on ‘Cutting Equipment’ or alternatively read the operator’s manual, which can usually be found on-line.

How do I measure a chainsaw bar?

If you need to replace your blade and aren’t sure of its length, you need to measure it from the front of the saw to the tip of the farthest cutter, rounded to the nearest inch. (See below)


This is known as the ‘called length’ and is different from the overall length of the bar.

What maintenance should I do on my bar?

You don’t need to be a rocket scientist to figure out that the saw’s cutting components get some pretty rough treatment. As well as supporting a fast moving chain, the blade can often get pinched in wood and bent with heavy use.

It’s therefore important that it is checked regularly and appropriate maintenance carried out.

Firstly, inspect it for wear and tear. This occurs mainly in two places: on the top side of the rails and on the surfaces inside the rails. The rails are the outer rims of the bar as shown below:


You should check regularly if there are any burrs (rough edges) on the bar and if so file them with a metal file.

Next, you should check if the bar’s groove has become badly worn.


If this is the case you may need to replace. If the groove is fine, then you should ensure that is clean and remove any debris and clean if necessary. Special tools, as shown below, can be purchased for less than $10.


Make sure the nose sprocket continues to move freely and that the lubricating hole is not blocked. Lubricate with grease if necessary.

Finally, most modern bars are reversible so you should turn it over at regular intervals to prolong its useful life.

What size chainsaw bar do I need?

The size of bar required will depend on the type of cutting you are planning to do.

If, for example, your intended use is just to do a little bit of light pruning then a smaller type is appropriate. Not only will this be lighter but will enable you to maneuver the saw better and get into tight spaces.

On the other hand, provided the saw is powerful enough, a longer bar will enable you to cut through a larger diameter piece of wood in a single pass.

In terms of size, bars between 8-in and 14-in are best used for trimming, pruning and light cutting. They are also good for small tree cutting and removing tree limbs.

Sizes 16-in to 18-in are best for small tree cutting and removing tree limbs. They are also good for medium duty tree cutting and storm clean-up.

When you get to sizes, 20-in to 24-in, you will find that they are capable of handling most tasks around the home and farm. They are particularly suited for firewood and large tree cutting, as well as storm clean-up.

Bear in mind that the longer the cutting components the heavier the saw will be. This is not so much an issue if you are bucking logs, but if you are carrying out tasks which require a lot of maneuverability, fatigue is something to consider.

Do I need a specialist bar for carving?

When it comes to chainsaw carving, specialist bars have been designed to help with all that detailed work. They allow the user to take small bites out of the wood, as well as enabling you easily make plunge and bore cuts. (This is where the tip of the saw is pushed into the wood. Care is needed as kickback can occur when the tip of the saw comes into contact with wood).

Carving bars are also lightweight and easy to maneuver on small chainsaws. They come in different lengths and also with different size tips. They do not have sprocket noses as these wouldn’t be able to cope with the heat generated and stress that they are put under when carving.

Unfortunately, you can’t just buy a carving bar and attach it to your saw. You need to ensure that the chain sprocket (this is not the same as the nose sprocket) is the right size. Some carving bars have


very narrow tips. These ‘dime’ tips need a ¼ inch sprocket to run the small chains which will go round the tip of the bar. You can get larger tip bars but the dime tips are particularly popular as they allow for more detailed work to be carried out.

Who makes the best chainsaw bar?

Many chainsaw manufacturers produce their own cutting components. Stihl and Husqvarna are just two manufacturers who have quality products.

The leaders in the field, however, are Oregon. They produce hundreds of products, designed to fit pretty well every popular chainsaw on the market today.

As always, I hope this article has been useful in answering some of your guide bar questions.

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