FSA’s all-new and completely redesigned K-Force Light crankset wants to take on the titans, offering up a low weight and shifting performance that put it in the same sphere as the best cranks on the market.
It has some stiff competition, and FSA’s shifting has not historically stacked up well against the best. Frankly, nothing on the market shifts as well as a Shimano Dura-Ace 9000 crankset paired with the company’s latest Di2 front derailleur. The combination is a reference point for the entire industry and with few exceptions nothing comes close.
The new K-Force, featuring a propriety ring design similar to the one debuted on the latest Dura-Ace cranks, is one such exception. The shifting is drastically improved from the K-Force’s previous iteration, and is nearly as good as the reigning king, Dura-Ace.
The deficit is as small as the performance gap between Dura-Ace and Ultegra — both the K-Force and Ultegra cranksets perform perfectly well under normal shifting, but retain a minute yet unmistakable shift lag under high pedaling load. Dura-Ace has done away with that lag.
When we subbed the K-Force Light in for a SRAM Red crankset and paired it with a Red Yaw front derailleur, shifting improved slightly over the stock setup. So the FSA option may appeal to SRAM users most of all. It’s lighter and shifts better (and the latest Red is already very good), but it’s more expensive than the Red crank.
The drastic shifting improvement over the previous K-Force crankset isn’t wholly surprising given the cranks’ wholesale redesign, which placed a focus on both crank arm stiffness and, most importantly, chainring stiffness.
The new CNC aluminum chainrings are now proprietary, utilizing an 110BCD (bolt circle diameter with asymmetrical arms, much like Shimano’s 4-arm design. FSA calls its design Asymmetrical Bolt Spacing. Like SRAM, one bolt is now built into the crank arm itself, while the other four are spaced unevenly. The idea is to use less material while maintaining strength and stiffness, and, just as with Shimano’s design, it seems to have worked.
The downside, of course, is that you’re stuck with FSA rings. The upside is a much stiffer system, which drastically improves shifting. Flexy rings kill shifting performance even with the stiffest front derailleur. While the multitude of patents Shimano holds over its ramp and pin designs have thus far prevented any competitor from matching its front shifting performance, brands like FSA can make up most of the difference by developing ferociously stiff chainrings.
FSA’s use of the versatile BB386 EVO standard is welcome, allowing the K-Force Light crankset to be easily fitted to frames with the EVO, BB30, or PF30 standards. BB30 and PF30 frames will require an adapter (available from FSA). An English BB version is available as well.
Weight of the K-Force Light is excellent. Our 172.5mm, 50/34-tooth set weighs 594 grams. That’s well ahead of the 608 grams for the same SRAM Red setup and 649 grams for Shimano Dura-Ace. Campagnolo’s Super Record Ultra Torque crankset, with a Ti spindle, is about 10 grams lighter but costs a whopping $1,000.
Retail price, $725 for the standard option and $700 for compact, is competitive with the Dura-Ace crank, but doesn’t stack up well against SRAM, which can be had for more than $200 less.
Bottom bracket prices are reasonable. EVO, BB30, PF30 and English are all available, $200 for ceramic versions or $50 for standard steel. Adapters for the BB30 and PF30 bottom brackets are an additional $20.
The K-Force should appeal to SRAM users seeking even better shifting, weight-conscious Shimano users, or Shimano users who want to take advantage of their frames’ oversized BB386 EVO, BB30, or PF30 bottom bracket shells. It certainly won’t appeal to anyone on a budget.