Chain Guides & Bash Guards

Chain guides and bash guards have very different tasks, but they have one thing in common: both are mounted around the front chainring (rarely multiple front chainrings). Some manufacturers therefore integrate both functions into a single product. Read further and discover more.

Chain guides on mountain bikes, gravel bikes and where else?

A chain guide is designed to prevent the chain from falling off the front chainring in the event of strong vibrations. This could damage the frame or the crank or, in the worst case, lead to a fall. On the rear sprockets, the rear derailleur takes over this function. And although in recent years 1x drivetrains with special chainrings (such as the well-known narrow-width profiles) and vibration-damped rear derailleurs provide good chain guidance and reduce the likelihood of losing the chain, the "real" chain guide at the front is by no means outdated. It makes a lot of sense and plays to its strengths in places where the ground conditions become particularly rough. That's why today it is mainly used in technically demanding trail, enduro and downhill mountain biking, but also has its uses on gravel bikes. On road bikes, chain guides are much more minimalist than on MTBs. By the way: if you use a chain guide and can switch off the vibration damping on the rear derailleur, you will be rewarded with a more responsive rear suspension and smoother shifting. There are one-piece chain guides such as those from 77designz or OneUp Components that guide the chain above the chainring and are particularly lightweight. Two-piece guides like the classics from MRP and e*thirteen guide the chain above and below the chainring. They offer even better chain guidance, but are also heavier, more sensitive to dirt and increase friction in the system.

Chain guides for single derailleurs and front derailleurs

On mountain bikes, single derailleurs with only one chainring at the front have become widely accepted. You can also use a separate chain guide if you want to go all out with two chainrings. Above the chainring, the front derailleur takes over this task; below, the chain runs safely over guide rollers or sliders.

Chain guides on e-mountain bikes

Many e-bikes and especially e-mountain bikes come equipped with chain guides. The risk of chain loss leading to damage or a fall is even higher here. Whereas an experienced biker can feel that the chain has fallen off and stop pedalling, a drivetrain on an e-bike can "push" and thus exacerbate the problem. Nevertheless, you should not simply retrofit a chain guide on an e-bike, but rather carefully study the specifications laid out by the bike manufacturer. Shimano for example offers chain guides for STEPS motors.

Bash guards on the mountain bike

On mountain bikes, bash guards protect the chainring(s) and the chain itself from damage in the event of a collision and from stones. As with chain guides, the more technical the terrain, the more sensible bash guards are – by the way, also and especially uphill. If you need a bash guard on a mountain bike, you will probably also want a chain guide. Then, in any case, take a look at the integrated solutions, e.g. from e*thirteen or MRP. However, there are also lighter versions without additional chain guides, called crash plates or – because of their shape – "tacos". With many integrated bash guards with chain guides, you can simply replace the lower taco part when it has done its job. Another form of impact protection is the bash ring (or rock ring), which is mounted directly on the chainring.

Special case: chain guards on everyday bikes

There are also chain guards on everyday and touring bikes, e.g. from Shimano. They are similar to the bash guard on the mountain bike, but they are much lighter and not as stable. First and foremost, they protect your trousers from getting caught or smudged in the chain. However, they also protect the chain and chainring to a certain extent in the event of unintentional contact with bike stands, falls or kicked-up stones.

ISCG: Universal mounting of chain guides and bash guards

If your mountain bike is equipped with ISCG tabs ("International Standard Chain Guide"), you are in luck. The current standard is called ISCG05 and allows for easy and precise installation of chain guides and/or bash guards at three mounting points firmly bolted around the bottom bracket. Installation and alignment are so easy. There are also direct mount chain guides that are attached to a specially prepared mounting point on the seat tube. Chain guides for bottom bracket mounting are fixed between the frame and the bottom bracket shells. A special case are the minimalist chain guide tubes like those from 3min19sec or Exustar, which attach to the chainstay of your bike and work for single as well as multiple gears. Bash guards are often firmly bolted to the ISCG tabs, but there are also direct mount variants for mounting on the frame.