Fox Live Valve electronically controlled suspension: the future is now

by Dave Rome


Fox’s Live Valve electronically controlled suspension system has long been rumoured and seen in testing by many of its professional riders, and now it’s finally official. Instead of relying on manual lockout levers or clever suspension linkage kinematics to balance ride quality and pedaling efficiency, Live Valve uses electronic sensors to actively automate damping adjustments based on the terrain with no input required from the rider. Assuming it all works as intended, this means you can have that buttery smooth suspension on the descents, but also full efficiency when on the pedals – all without having to do anything other than ride.

Such automation isn’t the first of its kind; about five years ago, Lapierre and RockShox joined forces for the e:i suspension system. And more recently, Pinarello introduced the Dogma K10S Disk, a bike with an electronically-controlled softtail shock.

However, compared to the Lapierre and RockShox collaboration, Live Valve goes about it in a simpler and more effective way. It’s also more reactive, and can be implemented onto just about any mountain bike and with fewer pieces to go wrong. The tech is no doubt interesting, but it’s perhaps where the tech could go from here that’s even more exciting.

What is Fox Live Valve and how does it work?

Fox Live Valve Suspension 2019 fork damper
Think of Live Valve as a lockout switch that is automatically flicked off and on to match the terrain before you can even think about.

Fox Live Valve detects bumps inputs at both wheels and the angle of the bike using accelerometers placed at the fork, rear axle, and main triangle. This information is sent to the suspension controller at a claimed rate of 1,000 times a second. The system interprets this information and reacts within three milliseconds (100 times faster than the blink of an eye), opening and closing solenoids at both the front and rear shocks to adjust to the changing terrain. Technically speaking, this means that Live Valve doesn’t exactly predict what sort of terrain is coming. However, the company claims that the system reacts so quickly that you don’t even realize that it’s working.

Fox may only just now be introducing Live Valve technology to the mountain bike space, but it’s already been implemented in the automotive industry: first on Polaris Dynamic UTVs, and more recently, on the 2019 Ford F-150 Raptor. Live Valve isn’t the first time Fox has implemented electronics on its mountain bike suspension, either, with the recent iCD system offering electronic lockout controls and Shimano Di2 integration for cross-country racers. Although iCD was still basically just a fancy manual lockout, it still provided valuable information. According to Fox, iCD-equipped cross country racers used their lockouts more than twice as often than those with a traditional manual lockout – up to 90 times in a single 1.5-hour race. By comparison, Live Valve supposedly makes 720 changes in the same time frame.

Fox Live Valve Suspension 2019 battery
Mounted to the frame, the external battery acts at the system controller, charge point, and computer.

Unlike iCD, which relied on a Shimano Di2 battery for power, Live Valve uses its own externally-mounted 800mAh USB-rechargeable lithium-ion battery. Also tucked away inside the tidy battery case is one of the system’s accelerometer and position sensors, as well as the system controller that process all of the incoming information. Among other things, it’s responsible for determining bike pitch and whether the bike is jumping or in free fall. The pitch detection uses an algorithm that assumes three states: uphill, downhill, or flat ground. Sensors at each wheel determine whether the terrain is rough or smooth, and all of the system components are connected via physical wires. According to Fox, wireless systems are visually tidier, but also more complex – and more importantly, they’re still too slow to react relative to wired systems.

With Live Valve, the suspension remains closed over smooth terrain and then opens once a bump is detected at the wheel. The sensor at the front wheel will open both front and rear suspension and start a timer. If it’s a single bump and no further bumps are detected, then the timer will automatically set the suspension back to the closed mode. However, that timer is reset with each successive bump, and so the suspension will remain open on a rocky or technical descent. The timer system means that the battery only has to send a signal to the solenoids in the dampers once per suspension event, thus conserving system battery life. Speaking of which, Fox only vaguely states that the Live Valve battery will last for “16 to 20 hours of ride time,” with a full recharge taking just over 1.5 hours. And in the event you forget to charge the battery and the battery dies, the system will default to the open mode on both the rear shock and fork.

Fox Live Valve Suspension 2019 fork damper
Most traditional suspension adjustments remain available to the user. Even low speed compression can be tuned with a 3mm hex key.

As fancy as Live Valve sounds, it still only affects the compression damper; much of the suspension setup otherwise remains the same. Air spring pressure, rebound adjustments, and the firmness of the open mode setting are also customizable by the rider. Riders can also tune the overall sensitivity of the Live Valve – in other words, how big an impact is required before the system reacts. However, the firmness of the closed mode is preset.

As expected, there is a small weight penalty for adding Live Valve to your bike – an extra 144g relative to the cable-actuated remote system on a 2018 Scott Genius, for example. More specifically, the battery is 72g, the controller and sensors are 104g, a Live Valve rear shock is quoted at 466g (185x55mm trunion mount), and a Live Valve fork damper by itself is 249g (sized for a 160mm-travel Fox 36 29er fork).

Fox Live Valve Suspension 2019 front fork sensor
The front wheel sensor is attached to the fork crown. While the rear wheel sensor sits just below the rear brake caliper.

Fox clearly believes that its Live Valve technology is relevant wherever there’s lots of pedaling required. As a result, the technology is available across Fox’s whole air-sprung range, with the exception of its downhill-focused products. The system was designed to be mounted externally, allowing it to be retrofitted to most mountain bikes already on the market.

A number of brands are expected to use Live Valve suspension on top-tier models, with Giant, Pivot, and Scott already committed to it for 2019 bikes. Pivot and Rocky Mountain are the only brands to offer specific frame compatibility with Live Valve, including a dedicated battery mounting point. Aftermarket systems (including fork, shock, controller, and sensors) will be available in 32 Step-Cast, 34, 34 Step-Cast, and 36 fork configurations. System prices start at US$3,000, which is approximately US$1,400 more than a regular top-tier suspension package from Fox.

Fox-Live-Valve-Suspension-release-2019 on Pivot Mach 4
Pivot is just one brand to be offering Live Valve for 2019.

Future speculation and application

With such new technology, it may seem odd that we’re already speculating on what’s next. However, despite Fox’s years of development, it’s clear that the technology is still in its infancy.

Fox built Live Valve as an external system for easy bike compatibility, and it’s easy to imagine that the next step will be a system built around frame integration. A similar thing happened to Shimano Di2 in its second generation, and as a result, bikes became more visually appealing and weights dropped (although marginally).

Fox Live Valve Suspension 2019 rear shock
Pivot’s latest frames put the battery somewhat out of the way.

Unless you have the latest frame from Pivot or Rocky Mountain, the Live Valve battery currently mounts to a bidon cage boss. It’s likely Fox has a solution to place the battery below the bottle cage (like was the case with first-gen Di2), but equipped bikes currently show it taking the spot of a bidon, a likely deal breaker for any cross-country rider. Certainly expect to see more frames offering cleaner integration with Live Valve, especially given such a change on most frames would likely only require a couple of extra rivnuts and perhaps wiring provisions, rather than a whole new frame design.

With the battery acting as the central control unit, it’s unlikely we’ll see an integration with Shimano Di2 return anytime soon; despite how well Di2 works off-road, its adoption has been less-than-widespread. However, such a collaboration shouldn’t be ruled out entirely, and a central battery unit would open up the technology to being more competitive on the scales and with increased purpose.

Dropper seaposts also allow room for further integration, especially with many brands working on electronically controlled posts. Such a thing could at a minimum share the Live Valve battery. Taking it a step further, such integration could offer automated dropper post control based simply on the pitch of the ground.

If such technology continues to be improved – with prices and weights coming down – then it’s possible to consider that frame designs could change, too. For example, suspension kinematics could theoretically be optimised solely for descending instead of currently having to balance ride quality and pedaling efficiency.

And finally, any technology that has the potential to make mountain bikes more efficient with less rider input has potential applications in other disciplines, such as on gravel bikes or even road suspension like Specialized’s FutureShock. Pinarello may have been the first to bring similar automated suspension tech to the road, but it’s advancements like Fox’s Live Valve that will push it into new space.

Fox’s Live Valve technology raises a number of important questions: Does all this sophisticated technology take away from the experience and purpose of being out in the wild? Or does it simply add to the ride experience, allowing you to focus on the trail and the surroundings, and less on what your bike is doing (or not doing)?

Editors Picks