It is not really much of a challenge to make a super-stiff crank set. Using heavy materials like tubular chromoly, or solid steel it is possible to make an exceedingly stiff crank. The real challenge, and the greatest benefit to real world riders, is to create the exceptional balance between weight and stiffness. FSA's K-Force Light crankset has the highest stiffness to weight ratio when compared to other options - the proof is in the numbers. Consider the following test conducted by the independent laboratory EFBe in Germany: EFBe used a load frame to calculate the deflection of each crankset for a specified force. EFBe then used this information to calculate the elastic modulus (stiffness) for each crankset. From this information, it is possible to determine the stiffness to weight ratio of each crankset. The stiffness to weight ratio consists of the elastic modulus divided by the weight of the crank arms, spindle, and chainring. EFBe is an independent testing firm located in Waltrop, Germany. For more information about standards and procedures, see their website: www.efbe.de

K-Force Light is the first FSA crankset to come with a ceramic bearing bottom bracket. FSA ceramic ball bearings are up to 10 times harder, 50 grams lighter (per bb), and maintain a surface perfection that is much higher than steel bearings, allowing for a 3-4% reduction in mechanical friction. Tests by the Danish magazine Cykel-Motion (Mar 2005) and subsequently supported by calculation, show how using ceramic bearings can reduce rolling resistance by 50%, saving 22m in just 55 seconds at 32kph. In short, astounding speed improvement of 4%. Further tests confirmed by the Danish cycle magazine Cykel Magasinet (Sep 2005), describe dramatic reductions in friction compared to conventional cycle bearings. For example: With a pair of race wheels (total of six bearings), friction with ceramic bearings is reduced 22 fold While Dura Ace pulleys consume 0.78W @ 500rpm, ceramic pulleys use less than 0.06W A Record BB @ 100rpm and 400W consumes 0.6W, the same BB with ceramic bearings consumes 0.02W Such improvement is unheard of, even in this day of advanced bicycle technology.So, it comes as no surprise to learn that top professional riders are already using these amazing bearings to win major races. Full Speed Ahead has been testing ceramic bearings with our teams for the past two years. The results are great, teams and riders are convinced. The friction reduction of ceramic bearings aids a wide variety of riders. Unlike aerodynamic features, which only the fastest riders enjoy, the advantage of ceramic units is greater at lower speeds. This is a crucial difference between aerodynamic resistance, which increases exponentially with speed; and mechanical friction, which increases in direct proportion to speed.From a technical point of view, riders sheltered inside the peleton or riding off road have more to gain with ceramic bearings. Ceramic bearings last longer, perhaps 5-10 times more. From a strictly economic perspective, they¹re less expensive to run even without considering the labor savings.

Engineers know that bending and torsional stresses transmit through the outermost shell of any structure. Thus, the design goal for a crankset should be to move material away from the neutral axis of the structure. The resulting structure is known as a monocoque. Due to the intricacies of the carbon molding process, most other carbon cranksets have some internal structure which adds unnecessary weight. The internal structure of other cranksets generally consists of an alloy or carbon spine and/or expanding foam. Carbon internal spline cranks use a multi-step process: in the first step, the carbon spine is formed, secondly the spine is wrapped in high density expanding foam, and finally the carbon outer shell is formed. Other cranks use an alloy internal spine with foam or simply foam alone. Now there is an alternative..... "nothing". FSA has developed an exclusive bladder molding process for the K-Force Light crankset, enabling a true high modulus carbon fiber monocoque structure. The resulting shape is hollow inside. Not only are the arms hollow, but the hollow cavity also extends completely around the spider. Only a slender I-beam shape remains inside the outer skin to carry shear stresses through the body. All excess internal weight has been removed from the structure, yielding an unbelievable weight of 633 grams for the crankset, bottom bracket, spindle, and chainrings. No comparable crankset is lighter.

If you think FSA has sacrificed strength for weight, think again. The Center for European Normalization (CEN), the International Organization for Standardization (ISO), the German Institute for Normalization (DIN), and the Japanese Industrial Standard (JIS) are just a sampling of the cycling specific test standards FSA has met and exceeded. Not only does FSA continuously benchmark their own products and those of their competitors, FSA also evaluates the test parameters themselves. For the K-Force Light crankset, FSA engineers went above and beyond any published test methods, developing proprietary fatigue, yield, and impact test equipment and procedures. Continuous testing and refinement throughout the development process have allowed FSA engineers to optimize the bonding interface between carbon and alloy components of the crankset, to develop an entirely new bomb-proof spindle interface, and to optimize the stiffness of the carbon structure.The end result is a crankset which is not only exceptionally light, but also possesses excellent stiffness, fatigue and ultimate strength characteristics. Right: Pneumatic Fatigue Test Machine is a FSA custom-made test apparatus that, coupled with LabView software, can be reconfigured and programmed for a variety of fatigue, impact and yield tests. Such load frames, along with numerous other destructive test machines and important rider feedback, were used extensively during the development of the K-Force Light crankset. The K-Force Light Crankset is CEN Tested and approved. For more information on CEN standards, see www.cenorm.be