The E*thirteen Components XCX ST seat tube-mounted guide is a simple and effective guide for racers and trail riders who want go to a single ring setup, but don't want the weight of a full size chain guide or have ISCG mounts on their frame.

E13 XCX ST chain guide for bikes without ISCG tabs

The E*thirteen Components XCX ST chain guide mounts to the seat tube and comes with three shims to fit 28.6, 31.8 and 34.9mm tubes. The shims are eccentric, so you can rotate them to shift the guide into the correct position to get the right chain line. You don't need to break the chain to fit, the front bolt allows the cage to pivot open.

Fitting is really easy, and adjusting for optimum chain clearance is a doddle. There's a stack of vertical adjustment which lets you put the guide in just the right position over the chain ring. Not sure where to fit it? Look at your front mech cage for a guide.

Polycarbonate cage with honeycomb construction to save weight

The XCX is compatible with 32 to 44-tooth chain rings. I used it with a 36-tooth ring and it was fine. Okay, so I was over geared on a couple of the steeper ascents in the Surrey Hills, but nothing a bit of grunting and gurning didn't solve. Don't think it's just super strong people who will benefit, as with the right combination of chain ring and cassette, you can scale most hills without too much trouble.

And besides, it seems like everybody is going to a single ring setup these days, from cross-country racers to trail riders, and it's easy to see why. You can save a decent amount of weight in ditching the shifter, front mech and one or two chain rings (depending on your chainset configuration). You also have a new simplicity to your riding, and there's less chain of losing the chain off the front.

Split clamp makes fitting easy

In use it worked very well, offering a near silent ride even over ground that gets the chain slapping the chainstays. And the chain never derailed, as there's sufficient overlap of the large guide.

It's a very nicely made bit of kit too, as it should be for £80. That's a lot of money. The mounting bracket and backplate is machined from aluminium so as to be as stiff as possible and the cage is made from polycarbonate. There's some nice detail work with excess material being machined away, including a honeycomb construction on the inner slider.

Weight is 76g on our scales.


If your frame doesn't have ISCG tabs but you want to go 1x10, the E13 XCX offers an easy and reliable way of ditching the inner ring and front mech. A tad pricy though.


Chainguide for frames without ISCG tabs

Simple setup

Quiet in use


A bit pricy

Price: £89.95

UK Importer: Silverfish

More information: E*thirteen Components XCX ST chain guide

What E*thirteen Components says about the XCX ST chain guide

  • Primary Uses: XC Race, 1-by set-ups
  • Available in both high and low mount clamp backplates
  • Includes chainline alignment cams (set of 3)
  • Extremely light at 71-75 grams!
  • World Championship gold medal-proven top slider design
  • Easily change chains and chainrings without removing slider
  • Captive gold anodized alloy hardware
  • Gear range of 32T - 44T, small enough for the steep Mont Saint Anne climbs and big enough to win Glouchester, Massachusetts
  • 7075 aluminium backplate

E Thirteen XCX-ST Chain Guide Specifications:

  • Weight: 71-75 Grams
  • Chainring size compatibility: 32T - 44T
  • Chainline adjustment: 50-53mm
  • Seat tube diameter: 28.6, 31.8, 34.9