- - FSA Officially Unveils Its K-Force "WE" Semi-Wireless Groupset

FSA Officially Unveils Its K-Force “WE” Semi-Wireless Groupset


FSA officially broke cover with its much anticipated 11-speed, semi-wireless K-Force WE electronic groupset today.

The WE groupset relies upon ANT+ for its shift levers to communicate wirelessly to the front and rear derailleurs, using a proprietary network key and customized communication protocol that ensures it’s secure, safe, reliable and efficient.

According to FSA, customization played a major role in the development of the WE, which includes a proprietary companion app that enables users to adjust the drivetrain settings to coincided with shifting preferences – similar to how Shimano’s Di2 works.

In addition, the app also provides a shift count, as well as battery management, wherein FSA says it’s able to calculate the remaining battery life based on use and the number of shifts made.

The We’s battery itself is concealed inside the seat tube, and it has the ability to hold a charge up to 2000 to 3000 miles, which can be charged via the front derailleur.


As far as the brake levers are concerned, FSA offers two lengths, standard or compact, which both feature adjustable reach.

Meanwhile, the small coin battery is neatly concealed inside the “hoods”.  


The WE’s front derailleur is considered the “operation center” of the groupset, which unlike Di2, does not make use of an individual junction box, but rather everything is housed inside.

The front derailleur uses a rack and pinion mechanism for precise, quiet and rapid shifting, which also performs auto “trims”.


The WE’s rear derailleur features a lightweight carbon finish, along with composite pulleys, which uses a single arm construction and mini gearbox design, which has three small cogs to ensure precise shifting.

FSA is currently offering three cassette options for the WE, 11-23, 11-25 and 11-28, with the possibility of working with cassettes as large as 30t and 32t.


The crankset features hollow forged carbon arms with a forged aluminum BB386EVO axle, along with CNC machined chainrings, which has a brand new pin design that was specifically developed to improve shifting for the new electronic groupset.


Lastly, FSA developed new low-profile, new dual-pivot brake calipers for the WE, with the promise of flat mount, 140mm rotor disc-brake offerings to follow.

Expect to see more details and pricing on the K-Force We groupset during this week’s Eurobike Show. 

more from FSA…

WE are ready… ‘WE’ is ready! Introducing FSA’s brand new 11-speed electronic groupset, ‘K-Force WE’

FSA are proud to share with you the brand new electronic groupset, set to bring the quality, speed, control, familiar feel, reliability, value and longevity you expect from FSA to the worldwide cycling market. With K-Force WE, we are also putting the control, configuration and customisability in the hands of every rider – literally!

WE stands for Wireless Electronic. K-Force WE is a true whole new groupset: from the carbon shifter levers, the carefully crafted switchgear and the game-changing front and rear derailleurs, the hidden long-life battery pack, to the redesigned K-Force crankset, chainrings, cassette and newly uprated brakes.

K-Force WE is an 11-speed system that’s set for double cranksets. It features a revolutionary rear derailleur design and a front mech with the system’s ‘brain’ and rider-friendly control system.

K-Force WE is, in effect, a ‘hybrid wireless’ – the best of both worlds, and the result of extensive innovation, research, design, and testing over years with professional riders from a number of teams, countries and disciplines. The front and rear derailleurs and the battery pack are connected via a wire hidden in the driveside chainstays and seat-tube, while the rider-configurable shifters are fully wireless, each powered by a lightweight, long-lasting battery.

The benefits for this design approach are found in the optimum blend of efficient, precise functionality, long-term reliability, weight-saving and ease of use, charging and maintenance (including for the future fitting aero/TT bars).

As K-Force WE’s wireless signals are transmitted via ANT+, there are enormous opportunities to record and share a world of data. FSA have produced proprietary software apps, and worked closely on integration with market-leading headunit maker Garmin, and there is compatibility with many other ANT+-equipped bike computers.

Thanks to a combination of innovative design and the optimum nomination of weight-saving, strong and durable components, the overall weight of the K-Force WE drivetrain is just 2090g.

Control and customization has been a key theme throughout K-Force WE’s concept and development – the ability to adapt and configure the system to your own requirements features across the groupset’s individual components. Let’s look at each of them in turn…


K-Force WE’s shifters are a work of art – and the element of the groupset where the maxim of ergonomic rider-customization is most evident. The unidirectional carbon fiber levers house fully wireless shifters that can be set to each rider’s requirements.

The shifters operate on rocker switches on the outside of each lever blade. Their position, size and subtly textured surface ensures that they are easy to reach and operate both with bare fingers and when riding mitts or thin or full winter gloves.

You can make either single gear shifts with the familiar single tap, or shift multiple gears up or down by holding the appropriate button engaged. A slight delay has been engineered in so that you don’t accidentally shift by two or more gears when you only want one.

The size, shape and texture of the hoods has been subject to maximum research and trialing – and heir comfort has been one of the top three factors identified by FSA’s celebrated development tester, Ivan Basso (who lists two Giro d’Italia overall victories and two Tour de France podiums on his extraordinary palmares – so knows a thing or two about long-ride comfort!).

The levers are available in two lengths – with 6mm difference between them – to suit every hand size and rider type. This is complemented by the fact that both have reach adjustability to three different positions – all you need to do to alter this is turn a screw located under the rubber hoods.

The shifter operation is fully customisable. You can set either left or right shifter to operate either the front or rear mech. And setting whether the top or lower switch shifts the gears up or down is, again, an easy operation for any rider.

The wireless shifters are each powered by a single ‘coin’ battery, positioned inside the hood. They will typically last around two years, depending on how much you ride, and your shifting patterns. CR2032 batteries are flat, light, easy to find, cheap to buy, and a simple job to swap yourself.

The longer levers will be more suited to riders with big hands, and sprinters. The shorter levers will ensure that all riders, including women and juniors, have the optimum fitting. A triathlon/ time trial-specific shifter is currently in development.

Front mech

Along with the front mech shifting cage itself, the neat, traditionally positioned front mech box also houses the K-Force WE’s digital control box (its ‘brain’). Here, signals are received via ANT+ from the shifters, and relayed directly to the front mech itself and by wire to the rear mechs.

Front derailleur mechanical movement is precise and near-instantaneous, resulting in direct, predictable, quiet and effective gear shifts every time. An auto-trimming (or micro-shifting) function means that K-Force WE continually corrects itself with microscopic realignments to keep perfectly in line – for optimum chain efficiency, minimal mechanical resistance, reduced chain and teeth wear and no nasty noises or surprises!

A combination of different appropriate materials are used, with carbon fiber a common element across all K-Force WE components to keep weight low, and the overall dimensions of the box are kept small and neat despite the advanced electronics it houses.

There’s a power button on top of the front derailleur box, so you can power down (or up) the whole system It’s easy to operate for storage and travel, so you don’t accidentally run down power while your bike is in its transport bag or box.

The small LED lights on the front derailleur indicate battery status: blue means fully charged; green indicates high battery charge level; yellow shows that it is lower; then the red light tells you that it will soon be time to recharge. In the unlikely event that you were to run out of charge while out on a ride, the K-Force WE safety system will force the front derailleur into the inner chainring position, so you’ll never be left with a gear you can’t push. (Alternatively, you can link it up through FSA’s app, which will show you exactly how many shifts you have left before your battery runs out.)

It’s a simple process for any rider to index K-Force WE gears: place the chain on the 6th sprocket and hold down the ‘set’ button on the front derailleur box. In set mode the derailleur can ‘micro step’, so the alignment of the rear derailleur and the upper and lower limit for the front derailleur can be adjusted and set.

The K-Force WE rear derailleur breaks the mold – it’s not a traditional parallelogram design, but a unique electronic-driven gearbox moving the cage across the cassette with immense precision.

Rear mech

K-Force WE’s rear derailleur is a highlight of innovation. Unlike anything else on the market as it’s not a traditional parallelogram design, but a unique electronic-driven gearbox moving the cage across the cassette with immense precision.

Adopting this direction has enabled us to produce a more compact design where the motor works in perfect synchronicity with the lightweight mechanical arm, transferring motion with minimised opportunity for loss of accuracy.

A miniature yet tough gearbox is powered by the motor based on signals transferred from the shifters. Three gears mesh to produce lateral movement and ensure that the sides of the cage stay parallel. Carbon fiber is used where possible to reduce weight and maintain strength.

Cranks, chainrings & cassettes

K-Force WE features new cranksets, chainrings and cassettes specific to the groupset.

Cranks are a new development based on the familiar K-Force models, with modifications including slightly thinner arms, resulting in a lower Q-factor (or ‘stance width’) – the distance between the outside of one crank arm to the outside of the opposite crank arm. Narrower is generally ergonomically superior for pedalling to match riders’ natural stance, and for aerodynamic efficiency when riding.

The spider mounts where the cranks join the chainrings is a new shape, which helps both with improved stiffness, and with accuracy of power meters. The effective and efficient ramps from the current K-Force Light chainrings are retained for K-Force WE.

Chainring sizes, both standard and compact, will be compatible with the groupset, from a lowest size of 34t for the lower chainring and up to a maximum size of 53t for the big ring. The maximum capacity of the front derailleur (i.e. the greatest difference in the number of teeth between bigger and smaller chainrings), is 17. The choice of cassettes immediately available are 11-25 and 11-28t, while an 11-32 option is under development and testing.


K-Force WE brakes are a high performance dual pivot design based on the existing K-Force Light model. Taking feedback from many riders across the pro peloton, FSA’s proven design has been equipped with even more stopping power. The redesign also accommodates wider rims – which are becoming more popular with riders around the world.

Modulation and control feel better than ever with the lightweight UD carbon levers with their length options and easy reach adjustment. K-Force WE’s new look release pivot is easy to access and operate, situated at the top of the brake mechanism.

Battery and charging

K-Force WE is powered by a single slimline tube battery that’s easily and securely mounted inside your bike’s seatpost. This position means no ingress of water or salt, so it’s well protected any effects of extreme temperature change are minimised. Because it does not need to be disturbed for recharging, it’s a case of fit-and-forget. Its minimised weight is carried centrally on the bike to ensure no adverse handling characteristics are introduced.

A single wire runs down through the seat-tube to the front derailleur and control box, and then through the chainstay to the rear mech. This protected routing ensures long-term reliability of performance with almost no weight penalty.

The 7.4v Li-ion battery has a run-time of around 4,000 to 6,000km – depending on riding and shifting style.

Recharge time is around 1.5hrs from empty to full, with the charger provided. To charge, you detach the electronic cable from the back of the rear derailleur and attach it to the supplied charger. There’s a neat locking system for the cable’s entry point to the lead into the rear derailleur – a simple turn of one allen-headed screw, and you can’t pull it out – nor can it rattle loose on a rough road or track.

Development, testing and ‘feel’

Our gratitude must go to the professional racers, their mechanics and support teams from Bora-Argon 18, Cofidis, Direct Énergie, Etixx Bike-Exchange and Tinkoff, amongst others, for testing – and special attention during the 2016 the Tour de France as we finalised specifications of the last prototype model. Look out for K-Force WE running on riders in the Vuelta a Espana.

FSA’s team of engineers have run testing regimes and discovered data and numbers in every way possible. We’ve shared the technical descriptions with you here, but we also had to share with you an aspect we’re truly proud of – the way K-Force WE feels. Rider reports all highlight how the K-Force WE shifts so rapidly, smoothly and reliably along with the comfort of the hoods and levers and the positive feel and feedback of the shifters themselves.

Our testers have put K-Force WE through punishing loads and every different road and weather conditions. We’ve tried shifting under load and up hills, with no adverse effects. We’ve put the transmission through the pain you should never inflict on your bike, ‘cross-chaining’ from the big ring and big cog, and experienced no jumping and no noise. We’ve pushed the new brakes to the limit and found full control and maximum stopping power at every turn and on every surface.

We’re proud of the results and are glad to bring the game-changing K-Force WE to market.


Full Speed Ahead

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