FSA SL-K Light CX Crankset

FSA’s SL-K Light range is well known for being a not too offensively priced (relatively speaking anyway) way of getting some carbon upgrades onto your bike. Their range of SL-K carbon cranksets is available for road and MTB, and distributors Windwave will also get them sent straight from the Italian factory for your cross bike too.

When it comes to upgrading your cyclcross crankset it's a bit of a battle of scraping around finding whatever is in stock, everyone does one, but it's either OEM or hard to find in stock. So most end up sourcing a regular road crankset and then buying some new chainrings (for those not aware, an extra compact 46/36 is the done thing). You see with the very recent exception of Shimano’s new CX specific stuff and Campagnolo's CX Power Torque, choice is often a little limited. Enter FSA.

These SL-K’s are available in BB386EVO, BB30 and MEGAEXO (tested here) BB standards. Crank arms are hollow carbon monocoque composite in construction and these are mated with a chromoly steel spindle (MEGAEXO only, other versions get an alloy spindle) and they’re 5-arm 110BCD in configuration. Crankarms can be had with the decals in red, white, pink or green (well the ‘K’s anyway). There’s a pleasing organic shape to the cranks and they’d look equally at home on a hand built Ti or steel bike as they would on some italian bling race wagon.

The CNC machined chainrings are available in black or silver. On the face of it they’re really handsome looking chainrings and contribute to what is a good looking crankset. Wear has been good so far and shifting has remained consistently good. The rings are suitably ramped and pinned and they’ve never missed a shift. We even hastily fitted the crankset with an already part worn Shimano 105 chain and that combo is still running fine now.

[their weight] puts them right in there amongst Shimano Dura-ace and SRAM Red...

Installation is a pretty standard affair. If you’re not familiar with MEGAEXO, just think of it as one of the rival variations of Shimano’s Hollowtech II with external bearing cups. Only instead of preloading and bolting like a stem/headset interface, the non-driveside crankarm has a self extracting hex bolt which uses a relatively high amount of torque to pull the crank onto the splines. It’s not totally foolproof and we put our hands up to getting over-excited trying to crush the wave washer that forms an interface between the crank and BB cup. The result was a split crankbolt, and upon downloading the latest installation guide online, it’s been clearly updated to warn against trying to flatten it (unlike the printed copy in the box) – oops! A quick grovelling call to Windwave and a new crank bolt later, we were good to go.

FSA quote the weight for the compact road version (50/34) as 646g, ours with the smaller rings weighed in at 630g which sounds about right, and that puts them right in there amongst Shimano Dura-ace and SRAM Red. The bottom bracket weighs in at another 100g. While the system isn’t quite as light as say Rotor’s offering, we’re only talking by another 30g or so and the FSA’s are comfortably cheaper.

Out of the blocks the stiffness of the cranks is noticeable giving a somewhat peppy feel to acceleration. The low, flat profile of the crankarms also give plenty of clearance which mean they work well with the bulkier MTB shoe you’ll likely be wearing on a cross bike. They replaced a set of Shimano 105s which are already somewhat acclaimed for their stiffness as much as their value, and the SL-Ks were at least as stiff, if not more so, despite being a full 120g lighter!

They’re certainly one of the nicest looking cranksets on the market!

We’ve also found the whole system to be reassuringly durable so far. The carbon crankarms have a generous coating of lacquer which is holding up nicely, and the decals are applied under this too. They’re certainly one of the nicest looking cranksets on the market! The bottom bracket is as smooth as the day it was fitted having seen 6 months action (although admittedly in the reasonable weather we’ve had this year).

The £429 price tag isn’t exactly cheap but it does slightly pip Dura-ace on price (MEGAEXO only, BB30 or BB386EVO is going to set you back £479). That said, when you factor in the cost of some new CX friendly chainrings for Dura-ace or SRAM Red, it does look very tempting value wise. In all we’ve found the SL-Ks to be faultless in performance and every bit a match for the competition.