The E*Thirteen XCX Race crank arms are made by a patented compression moulding process and bonded to an oversized 30mm alloy axle
E*thirteen XCX Race crank is by a fair margin the lightest on test and, it claims, the lightest production carbon crank on the market. 346g (actual) weight is around 60g less than the nearest equivalent, and a whooping 200g less than some on test.
No surprises then, it targets XC use, rather than full-on downhill or enduro. There’s no weight limit as such, but such a featherweight crank won’t be best suited to huge compressions or jumps, especially if you’re a heavier rider. Instead, E*thirteen’s product means racing snake trail and XC riders can dump over half a pound of (rotating) weight for no more cash than equivalents.
The driveside bolts with a self-extracting 8mm hex key, with the spindle/arm interface connecting via a three-sided polygon called P3. E*thirteen has used this design (derived from tanks) for years, saying it delivers a large contact patch and improved stiffness. It’s easy to install and creak-free, and we’ve had good long- term results from it.
The brand’s narrow/wide chainring is held in place with an alloy lockring, while the APS bearing preload adjuster is plastic. In use, there are two clear sensations: a lack of mass and a lack of outright solidity. The former is so noticeable; E*thirteen cranks whizz around like both feethave taken performance-enhancing drugs, or at least your shoes have dropped a big chunk of weight. This effect makes climbing feel easier and more efficient when spinning smaller gears.
The flipside, however, is this is clearly the flimsiest crank here, and really stomping to sprint on flat pedals, there’s minor twist and flex in the arms. The crank arms also feel a bit springy slapping over root or rock webs, or landing small drops or jumps, which possibly adds comfort, but also introduces a less solid, secure sensation and was a bit distracting for riders over 80kg.