You can spend thousands upgrading your gears these days, but the numero uno culprit when it comes to poor performance is the humble gear cable. This bit of thin wire can get gunked with mud, kink, snap unexpectedly and generally cause untold hours of merry mayhem, even with a top-end SRAM XX1 drivetrain.

The rear mech is more sensitive to cable issues than the front as it has to precisely shift across up to 11 sprockets, compared to a maximum of three chainrings on the front. It has to do this with a lower spring tension than on the front mech too, so it comes as no real surprise that dirty, damaged or poor-quality cables can cause so much havoc at the rear.

Even new bikes can suffer from errant shifting, and this is because many bike manufacturers scrimp on the quality of cables to save money. Not that we think the top priority for the prospective purchaser should be a new cable set — there’s an abundance of replacement cables available. Some last longer, some deal with crappy routing better, but rarely do they shift as well as Shimano cabling, which is what I’ve chosen for this month’s step-by-step tutorial.

Replacing a rear gear cable needs very few tools; it’s cheap, it will transform your shifting and it’s easy to do. So what are you waiting for?

For a step-by-step guide to this job, and loads more maintenance tips, see the May 2014 issue of MBR, out now.

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