Dirt Bike Chain Guides Explained

Dirt bike chain guides are installed on dirt bikes to prevent the chain from derailing. The chain guides also protect the dirt bike swing arm from chain wear and other parts from chain breakages.

In this post, we cover the following topics:

Next, we will explain in detail the importance and purpose of using dirt bike chain guides for added protection and limiting chain wear. If you are not yet convinced that you need one, you will be after reading this post.

What Are Dirt Bike Chain Guides?

The dirt bike chain guides primarily protect the chain from derailing, but they also help protect other parts of the dirt bike. The sprockets, rear swing arm, and engine case needs protection not only from direct impact damage, but from chain breakages and chain slaps.

It can be something as simple as ruts, cracks, ledges, logs and sticks—or sometimes also other debris—that damages the chain or the rear sprocket.

Typical dirt bike chain guide kits include three separate items: a rear sprocket chain guide, a front sprocket chain guide and a chain slider. They each provide protection in different scenarios and help prevent chain wear, breakages and chain derailing. For most dirt bikes, they can be bought as a set.

Now, let’s dive in deeper for each one of these.

Dirt bike chain guide parts shown on a dirt bike sitting on a center stand.
Different parts included in typical dirt bike chain guide kits.

Rear Sprocket Chain Guide

A rear sprocket chain guide is a block that mounts in front of the rear sprocket of a dirt bike. It wraps around the chain providing lift and direction and feeding the chain correctly into the sprocket while reducing chain slack effects.

The rear sprocket chain guide prevents the rear sprocket from direct impact damage as well as reducing chain slack causing chain derailment.

The rear sprocket chain guide effectively protects the sprocket and prevents sticks and rocks being lodged between the chain and the sprocket and causing chain breakages.

When you buy a complete dirt bike chain guide kit, the rear sprocket chain guide is typically included.

A black dirt bike chain guide block installed in front of the rear sprocket
Acerbis rear sprocket chain guide protects the chain from derailment as well as direct impact damage.

Front Sprocket Chain Guide

A front sprocket chain guide is installed in front if the front sprocket and its main purpose is to prevent engine case damage from snapped chain.

When a chain breaks, it can get lodged between the case and the sprocket and the force of the engine or engine brake can push the chain against the case and break it. In breakages, the front sprocket chain guide effectively guides the chain through the front sprocket without any damage.

It also adds protection from other debris getting lodged against the engine case.

When purchasing a front sprocket guide or a complete dirt bike chain guide kit, make sure that the front guide is acting as a case saver, or add one.

A black chain slider on a dirt bike covered in mud
The front sprocket chain guide helps save the engine case in chain breakages as well as prevent chain derailment.

Chain Sliders

A chain slider, also called as a front slider, is used to feed the chain onto the countershaft or the front sprocket. It works against derailment and can substantially decrease chain drag or resistance.

As the chain slider wraps around the swingarm, it also functions as a protective layer between the swingarm and the chain. In other words, it stops the chain from rubbing against the swingarm thus protecting both the swingarm and the chain from wear and damage by keeping the chain away from metal. This also significantly reduces chain noise and damage.

When buying the chain sliders, make sure to get the model specific part matching your dirt bike. Some aftermarket dirt bike chain guide kits use the same chain slider with the MX dirt bike models and may not fit your swing arm design.

Do I Need a Chain Guide on My Dirt Bike?

Short answer is: Yes!

If you are going to push your dirt bike to the max while riding in different types of uneven terrain—as one might expect—you should be certain that all systems and parts of your bike operate properly. The chain makes no exception.

Most dirt bikes come with a factory installed chain guide that installs in front of the rear sprocket. And you definitely want to keep it there.

Alternatively, if your bike doesn’t have one, you should invest in an aftermarket dirt bike chain guide kit.

A good dirt bike chain guide kit:

  • prevents rocks and sticks from jamming in between the chain and the sprocket;
  • prevents your foot from being gobbled up if you put them too close;
  • guides the chain from torquing and twisting when you ride;
  • keeps the chain out of the tire and rubbing the swing arm;
  • keeps rocks from bending the sprocket; 
  • increases direct impact damage protection;
  • saves the case in chain breakages;
  • and substantially extends the overall chain and sprocket life.

A dirt bike chain guide kit makes sure that when your chain rolls, it stays on the rear sprocket. To ensure that the chain moves smoothly, regularly check your chain guides for damage and replace them when needed.

Additional Dirt Bike Chain Protection Options

In addition to a dirt bike chain guides, there are also other ways to increase the protection of the chain and the sprocket. Here are few things to consider when it comes to protecting the vulnerable area around the chain.

Chain Rollers

Japanese dirt bikes, such as Honda, Suzuki, Kawasaki and Yamaha, have a round chain roller that protects the bottom cross-braces of the frame from the chain. It mounts to the frame right under the chain.

Without the roller to hold the chain up, the chain would rub on the frame. In addition, the roller keeps tension on the chain when the shock is at full compression. Without it, you could throw the chain and cause some damage to the case.

Chain rollers often have bearings inside that easily wear out. And once they do, they begin to wobble. So you want to keep an eye on them. Also, be careful when washing your bike with a pressure washer near the chain roller as water is not friendly to chain roller bearings.

The chain rollers are typically not part of the dirt bike chain guide kits and are sold as separate items.

Frame Pads

KTM and Husqvarna use an enlarged frame pad that has a similar function to a chain roller. They both make sure that the chain doesn’t drag on the swing arm. However, a frame pad does it without any moving parts.

A frame pad mounts under the chain slider on the frame. It lowers the chain friction and plate wear and keeps the drive chain in line and protects vital components.

Compared to a chain roller, a frame pad is less expensive to make and less likely to break. In addition, a frame pad increases durability although there’s potentially more drag with it.

Some graphics or plastics kit may include some form of frame pads. However, these type of frame graphics are used to protect the swing arm sides. The frame pads preventing chain wear are usually sold separate from the dirt bike chain guide kits.

Case Savers

In addition to a dirt bike chain guide kit, you should invest into a case saver. Some dirt bike chain guide kits include a front chain guide, that also acts as a case saver.

A case saver is a plastic, steel or aluminum bracket that installs on the top side of the front sprocket. It protects the chain from lodging itself into the engine case if the chain snaps.

Another thing that can save your case is a quality chain adjusted to the amount of slack recorded in the owner’s manual. So remember to take a look also at the chain itself and adjust it properly.

Countershaft Covers

A countershaft sprocket cover is a small cover that installs over the countershaft sprocket.

It keeps debris and mud from building up around the countershaft sprocket of your dirt bike. In addition, it prevents unwanted body parts or debris from being lodged between the sprocket, chain and engine case if you crash.

All dirt bikes usually come with some type of a countershaft cover straight from the manufacturer. We recommend keeping it there even though you might be tempted to remove so that you wouldn’t have to deal with cleaning it form the dirt buildup. But that’s exactly why it is there: to protect the countershaft sprocket from the debris.

These type of covers are not included in the dirt bike chain guide kits.

An orange chain guide and slider kit installed on a dirt bike

Dirt Bike Chain Guide Maintenance and Replacement

Like anything else, the dirt bike chain guides wear out over time. Using proper chain lubrication and cleaning, they do last a long time. The rear sprocket chain guide is likely the first one to wear out as it regularly takes direct hits while trail riding. The Acerbis dirt bike chain guide kit includes a replaceable lower guide that can be replaced quickly without removing the chain.

It is important to periodically check the chain guides and the chain slider for wear and damage as well as replace them along with the sprockets or the chain when needed.

Typical wear spots to inspect are the chain slider sections, where the chain eats its way through and starts rubbing into the swingarm. The rear sprocket chain guide can also bend or have debris inside causing the sprocket to rub against the chain guide.

It’s recommended to replace the entire dirt bike chain guide kit at the same time. This is true with a new dirt bike chain as the worn-out sliders and guides can quickly ruin your new chain.

Our Dirt Bike Chain Guide Recommendations

This section contains affiliate links. If you use these links to buy something we may earn a commission at no additional cost to you. As an Amazon Affiliate we earn from qualifying purchases.

Our favorite dirt bike chain guide system is sold by Acerbis.

Acerbis Chain Guide / Slider Kit (click to check the current price on Amazon.com) is a great kit that includes the rear sprocket chain guide and the chain slider to protect the case. The rear sprocket chain guide effectively protects the rear sprocket and has a replaceable lower insert. This kit is all you need.

The Acerbis chain guide block has a great feature; you can replace only the lower block on the rear sprocket chain guide. This allows for a quick block change without needing to remove the rear wheel or the chain.

Conclusions

Using a high quality dirt bike chain guide is a no-brainer. They save sprockets and chain and possibly your engine case in chain breakages.

Chain guides are a must for any type of single track riding and can save a lot of money. They are easy to install and inspect for wear plus they last a long time.

Unless your bike already comes with a dirt bike chain guide kit, consider buying one before hitting any advanced single trails or tougher terrain.

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