How to choose your MTB chain guide?

How to choose your MTB chain guide?

Can't get enough of your mountain bike chain chain that keeps derailing? The solution to your problem is to fit a chain guide. Here's how to choose the right one.

Standard

  • Type of mounting: BB mount, ISCG, ISCG 05, collar or Direct Mount
  • Number of MTB chainrings 1, 2 or 3
  • Large chainring teeth

Guide bar types

Chain guides are distinguished by the way they are attached to the frame.

When this accessory first appeared, as there were no specific brackets on the bikesthe bracket was placed between the bottom bracket and the MTB frameframe, much like a washer. This assembly is known as a BB-mount type. This device tended to turn on itself under light stress, and has become obsolete.

To improve the system, in 2003 the manufacturers developed a standardized 3-spoke bracket, installed directly on the frame, called the ISCG (International Standard Chain Guide). It can be identified by the distance between the two mounting points, which is approximately 47.7 mm. A.

Unfortunately, the distance between the ISCG lugs posed a problem with new-generation housings (such as Press Fit or BB30). In 2005, this system was revised, and a version with a distance of 55.92 mm between the two points is now available. B. This model is called ISCG05.

NOTE: So as not to confuse the two generations of ISCGs, the former has been renamed ISCG03 or ISCG old. Aand the new ISCG05 B.

You can also find other types of mounting, such as those that attach to your frame at the base with clamps of different diametersor in place of a derailleur Direct Mount derailleur, for example.

The model of guide bar to use will vary according to the number of chainrings you have. It's important to choose a model that's compatible with the number of chainrings on your mountain bike transmission. If you're using a 2 or 3-crankset crankset, the guide will only act on the lower part of the crankset, as your derailleur will do the rest of the work on the upper part.

Finally, you'll find information on gear compatibility. This refers to the number of teeth on the largest chainring of your mountain bike crankset. A chain guide marked "32/38", for example, may be suitable for a crankset with a large chainring having between 32 and 38 teeth.

Which chain guide to choose?

When you go off-track on a descent due to uneven terrain, the chain often exits at the bottom of the crankset rather than at the top. So it's best to choose a chain guide that operates on the lower part of the crankset, or both.

As for the rest, as I'm sure you've understood, you don't really have a choice: you'll need to identify the mounting standard on your frame, the number of chainrings and, finally, the toothing of the largest chainring.

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