- FSA K-Force MegaExo Cranks
FSA has been at the forefront of developing carbon cranks, with their first MTB carbon crank released in 2003. Things have moved on quite a bit since then, and the arms and spider are now made entirely from 3K carbon fibre, and with the supplied bottom bracket weigh in at 840g. This figure puts them somewhere between Shimano’s XT and XTR offerings.
The cranks are designed around the company’s spin on the two-piece outboard bearing standard which has transformed the way we pedal in the last couple of years. A 24mm hollow chromoly axle is permanently attached to the drive-side crank arm, and bolted to the spider are a collection of 22/32/44 chainrings. They’re CNC machined from 7075 aluminium and ramps and pins help with shifting duties. Torx-headed bolts hold them securely in place.
These cranks are clearly aimed at XC racers, or riders with deep pockets. Ignoring the price, we found the performance faultless. Installing them was an easy job, and while the bearings did feel a little tight upon fitting, they soon loosened up after a few miles, and are now silky smooth. Shifting is smooth and sharp, and is as good as the Shimano benchmark for shifting performance. A deep lacquer covers the carbon and has protected the finish well – we’re only just now beginning to spot the first signs of scuffing.
Available in 170 or 175mm crank arm lengths.
Positives: They’ll add a lot of kudos to any bike, light, stiff, shift great
Negatives: Expensive, you’re paying for the development costs of carbon cranks – a newer design has been released for next year
Verdict: Carbon cranks have come a long way since the early incarnations and now are serious rivals to the high-end aluminium models available. While we can’t fault their performance or looks, their price puts them firmly in the hands of those with very deep pockets - to put it into some sort of perspective, Shimano's lighter XTR cranks are about half the price.