Best chain guides: the best chain security and chainring protection

Clutched rear derailleurs and narrow-wide chainrings, for the most part, eliminated dropped chains, and in the minds of many have also made chain guides obsolete. However, for some, the peace of mind, not only for chain security but also protecting chainrings from rock strikes are worth the additional grams. 

With a few different designs and mounting options, read on for our picks of the best chain guides you can buy today, or head for the bottom of the page for a rundown of the differences.

The best chainguides you can buy today

Based out of Squamish, OneUp components is run by a few former Race Face folks, whose goal is to make clever, high-quality products that just work — the OneUp Components Bash Guide is just that.  Developed with input from top EWS racers, it features a reinforced nylon bash guard and an 8mm thick 7075-T6 Aluminium backplate.

The Boost- and oval-compatible chain guide comes with bash plates to protect 26T to 36T rings so that you’re not losing any ground clearance. OneUp includes all the sims you need to prevent any rubbing, and install only requires a single tool.

Coming out of Colorado, MRP’s 1x CS Chain Guide is the last resort for keeping your drivetrain spinning when the terrain has other plans. Loosely based on the design of the brand’s V3 chain guides, the 1x CS sees a glass-filled composite backplate and a nylon upper guide, ensuring your chainstays aligned over your chainrings noise-free. 

The CS guide mounts using two bolts, but requires ISCG-05 mounts; install is simple, and you can leave your crank and chainrings attached. The guide is compatible with Boost spaced cranks, and round chainrings up to 34T and oval chainrings up to 32T. Best of all, it will only set you back $40.

AbsoluteBlack is a relatively new player in drivetrain components with its bread-and-butter high-quality oval chainrings. The UK-based outfit says its bash guard is the only chain guide on the market designed specifically for oval chainrings. 

The backplate is made from 7075 aluminium, the cage and bash plate are made of the polymer composite, and AbsoluteBlack uses titanium hardware to eliminate unnecessary grams. The bash guide has an adjustable chain line from 43-53mm, making it compatible with non-Boost and Boost drivetrains. If you need access to the chain, the top cage is tool-free to open, and the chain guide plays nicely with 26-34T oval rings or 28-36T round rings.

We all have that one friend who has swapped all the bolts on their bike for titanium hardware because it saves 7g, and gets a bit overzealous with the Dremel tool to shave off unnecessary weight — literally. They also probably have lightweight drivetrain components, including chainrings, that are susceptible to damage if the wind blows the wrong direction.

For this person, the MRP Carbon chain guide is an ideal choice. The metal backplate has been replaced with carbon, and utilizes ISCG 05 tabs for mounting. Designed for chain lines of 49mm or wider, the upper guide is grooved and incorporates the backplate for added stiffness, and the nylon skid plate adds protection from chainring bruising rocks.

Shimano’s XTR components are smooth running and nearly flawless; however, even the best parts have their limit, and so the XTR SM-CD800 chain guide serves as a backup in the spiciest of trail situations. 

Available in ISCG 05, E-style, and D-Type mounts, the XTR guide is low profile, lightweight, stealthy, and designed to work best with the M9100 12-speed chain. Based around a 53mm chain line, the guide will take from 30-38T chainrings. 

Chainguides don’t have to be these massive monstrosities that will seemingly keep your chain attached following a nuclear blast. Ultimately, their primary purpose is to prevent your chain from bouncing over the edge.

And for that, the Nukeproof Low Direct-mount chain guide offers everything you need and nothing that you don't. It mounts directly to the front derailleur mount you’re probably not using and sees an anodized alloy base plate and composite top guide. The guide plays nice with chainrings from 28-32T and comes with all the washers you may need to get things running smooth and quiet. 

Ethirteen’s LG1 Plus has a modular design; you can customize the level protection, and how much extra chain security you may need — the lower slider can be removed entirely if not required. Three included shims make installing a breeze, especially compared to systems that use individual washers, which allows the chain guide to work with Boost and non-Boost drivetrains.

The sliders are polycarbonate and solvent resistant; the upper slides are not only tool-free but co-moulded with a soft rubber interior to cut down on noise. 

The folks at Wolf Tooth components are problem solvers, and they use high-quality CNC machined gear, with ultra-tight tolerances to achieve these solutions — the GnarWolf is one such solution. 

Available in direct-mount, ISCG 05, braze-on, and seat-tube mount versions, each is made from 6061-T6 aluminium with stainless steel hardware. The chain guide uses Wolf Tooth’s infinite chain line adjustment for chain lines between 48-54mm with no shims required; the GnarWolf will take 28-36T round and oval rings, and install is done with a 4mm hex. 

What you need to know about chain guides

1. Why you should run a chain guide

When you blast through a rock garden or rough and rooty section of trail, your chain bounces, A LOT, and can sometimes jump over the side of your chainrings. While clutched rear derailleurs do a pretty good job of holding your chain taught and narrowed wide chainrings grip chain links, each as its limits. A chain guide simply keeps your chain inline with the teeth on your chainring, so as the crank spins everything falls in place, no matter how rowdy things get.

2. Bash guard

Many chain guides also have a lower bash guard. This is essentially a small piece of plastic that sits below the bottom of your chainring to bear the brunt of impacts that would otherwise pose potential damage to your chainrings. These are designed to break away in the event of a bit impact to prevent damage to your frame, and some even come with multiple sizes to maximize ground clearance.

3. ISCG vs. ISCG 05

In typical bike industry form, there are two mounting standards for chain guides; each uses three bolts, which screw into tabs around the bottom bracket to hold the guide in place. 

We have bottom brackets and their ever-changing standards to thank for the dual chain guide mounting standards; as BBs became larger, the bolt circle diameter of the chain guide tabs had to increase, too. 

While ISCG tabs are the simplest way to attach a chain guide to your bike, not all frames have them. Because of this, we have chain guides that attach to the front derailleur mounts or around BB cups.