The modern so-called two-piece crank design has been adopted by almost every crankset manufacturer over the past two years and has largely replaced the venerable three-piece square tapered bottom bracket axle that was the industry standard for decades. The benefits of such a design are the speed, ease and simplicity with which these components can be fitted to a frame.
Experience shows though, that they are barely lighter than the recent three-piece designs that use a titanium bottom bracket axle and carbon cranks. There is a useful range of crank lengths available ranging from 170, 172.5 to 175mm and it is compatible with 9- or 10-speed Campagnolo and Shimano gear setups.
The 34-tooth inner chainring provides a useful range of crawler gears for the sportive rider without the weight penalty associated with a triple chainset – though I have come across many cyclists who maintain that the weight penalty of a’triple’is offset by the greater range of gears on offer, so we can assert that a compact chainset is better suited to the stronger rider.
FSA produces a short-cage front mech for this crankset that’s a little faster to shift from small to large chainrings but in most instances we discovered that a standard Shimano or Campagnolo front mech shifted the chain quietly and smoothly between the chainrings.
The K-Force is 180g lighter than the Shimano Ultegra R700 and 240g less than the Campagnolo Veloce UT chainsets but, with a recommended retail price three times higher, it is expensive. On the other hand, we have seen the 175mm length versions of this crank for half this price, in which case they would certainly be worth considering if you have already bought the lightest set of wheels you can afford.
FSA also produces a short-cage front mech for this crankset for £33.95. But we found standard Shimano or Campag mechs worked fine.