"Just ride your bike." That's what Fox's Live Valve is all about. The premise is simple: Live Valve turns on your bike's suspension when you need it, and turns it off when you don't. Most trail bikes allow you to perform those functions manually, but the reality is that you are not smart enough to know exactly when to switch those levers, and even if you were, you would not be quick enough to switch them in time for your decisions to be effective. Live Valve gets it right every time. You push a button and ride your bike. Your suspension works. Pedaling feels seamless.
Suspension levers, anti-squat, platform damping, and inertia valves are all coping mechanisms. We optimize suspension kinematics between good pedaling and a good ride. We anticipate the trail ahead, make a best guess - maybe we'll turn something on or off - and then we live with the results until circumstances change dramatically enough to warrant a different decision.
How do I know these things? First, I've been riding dual-suspension mountain bikes since the beginning of mountain bike suspension, so I've had a chance to try every mechanical or electric suspension system that touts those abilities - including Live Valve. Second, while I'll freely admit I'm far from being the smartest guy in the sport, I have had the chance to ride with the most probable candidates and they all fall short of greatness in manual suspension mode. Third, the numbers don't lie.
Average human reaction time is .25 seconds for visual stimulus, and as short as .15 seconds for tactile stimulus - but those numbers are for people who are locked and loaded, not bouncing down a trail with a lot of other things to deal with. Controlled
The heart of Live Valve is Fox's patented "latching solenoid." It can toggle your shock's compression damping from open to firm in three thousandths of a second. Ian Collins photo
studies for auto accidents reveal much slower reaction times: 1.7 to 2.3 seconds before the brain can get the body to respond. Those figures may apply if you are riding a Scott or a Cannondale with a dual-remote suspension control, but if you plan on taking a hand off the grips and fumbling for a lever... taste eternity, my friend. By comparison, Fox Live Valve can sense an impact and respond in .003 seconds.
Fox Factory Image
How Live Valve Works
Fox Live Valve's heart is a magnetic valve a little larger than a pencil eraser that opens and closes the same low-speed compression circuit that is used for Fox's manually-controlled forks and shocks. This "latching solenoid" valve is packaged to fit inside both suspension components. The fork module simply replaces the damper-side top cap, while the shock module fits inside a second "piggyback" canister that sits parallel with the shock's IFP reservoir.
Two accelerometers, one in the fork arch, and another near the rear axle, sense and measure the velocity of vertical movement to register impacts. That information is sent through wires to Live Valve's microprocessor.
The fork and shock share the same solenoid-valve modules...
The front accelerometer is fixed to the back of the fork arch.
...Which greatly simplifies both service and installation. Ian Collins photos
The rear acclerometer is tucked behind the chainstay.
The brain of Live Valve is a small frame-mounted microprocessor (Fox calls it their Controller) that also houses a removable 7.4-volt battery. Key to the Controller is its cluster of sensors that indicate whether the bike is level, pointed up or down, or free falling. When an impact is sensed, the controller uses those four functions to determine whether it will open the fork, open the shock, or open both components. The interval between sensing an impact to opening the dampers is only three milliseconds - that's one hundred times faster than the blink of an eye. Opening the suspension's low-speed damping circuit in the nick of time, however, is only half of Live Valve's magic.
Live Valve's battery and Controller are combined into a single, compact module. This one is mounted to the down tube of Giant's 2019 Anthem Advanced Pro 29-0. Ian Collins photo
Live Valve's default is closed - the equivalent of you running your shock and fork in the firm pedaling mode. The Controller only opens the suspension after an impact, and it has a pre-set timer that tells it when to switch the servo module back to firm. The magic is that the controller consults its "tilt" and zero-gravity "Free Fall" sensors and alters its timing sequences accordingly:
Climbing: When you are climbing, the processor only opens the suspension component that experiences the impact - and then it closes it down immediately after to maintain support. That keeps the front wheel pinned to the trail and prevents the rear end of the bike from wallowing down in its travel.
Level: While you are riding level, the Controller uses either accelerometer signal to open both the fork and shock. This ensures the suspension will be balanced while cornering and pumping the bike. In level mode, the time interval to switch back to firm is lengthened, so the suspension will remain open to react to successive impacts, but not so long that out of the saddle pedaling will cause the bike to wallow into its suspension travel.
Everet Ericksen, Fox's Advanced Technology Group Manager, said that they delayed Live Valve's release three years to work further with riders and OEMs to construct new algorithms that play better with suspension kinematics and with varying terrain. It was a good call. Ian Collins photo
Descending: When the Controller senses the bike is angled downhill more than six degrees (the grade-angle can be programmed), impacts from either wheel will simultaneously open both the shock and fork, while the time interval to return to firm mode is further extended to ensure that the suspension feels unimpeded. It will return to firm mode if the terrain is smooth, so you can win downhill road sprints on the way home.
Free fall: Free-fall is sensed only by the Controller, which opens the fork and shock until the frame and fork-mounted accelerometers register that you have returned to earth and the bike is rolling smoothly again.
The takeaway here is that Fox developed an algorithm that senses what you are doing on the trail and tailors the suspension to enhance that experience. The addition of the tilt and free fall function also assures that Live Valve won't get confused while you are smashing through crazy zones.
Live valve's Controller senses if you are climbing, level, or descending and then either lengthens or shortens the time interval from open to firm compression modes. Tapping the accelerometer opens the solenoid (first click). If there is no following impact, the Controller's internal timer switches the valve back to firm (second click).
Don't worry about losing your conventional adjustments and clickers. Because Live Valve only affects the adjustable low-speed compression damping circuits, all other functions of the fork or shock are the same, including the damping piston's valve stacks, external rebound dials, and air cans. Manual low-speed compression adjustments are made via a flush Allen-hex screw in the face of the Live Valve modules. It's not as pretty as an anodized dial, but it gets the job done.
Live Valve has a threshold adjustment that alters the bump sensitivity of the system. Five pre-programmed options are available, accessed by an external button above the on/off switch on the processor. Green LED lights on the processor momentarily remind you of which setting you have chosen when you turn the system on. Scrolling from option one through option five increases the G-force necessary to open the suspension and decreases the time interval that the fork and shock will remain open.
Live Valve always remains open for air-time and in rowdy terrain, Fox's downhill settings will remain open full time. That is when most of us want our suspension to work full time anyway. Switching to a higher threshold setting creates a firmer pedaling feel, especially while pushing big gears, where some riders want the timer to close down earlier at the expense of a proportionately harsher feel over chatter and roots. In most settings, however, only the small-bump sensitivity changes. Medium and large hits feel much the same.
All five of Live Valve's pre-set suspension modes can be customized using a PC computer and a standard USB cable. Presently, however, Fox only offers the software to OEM customers and service centers. Fox Image
Can I Program Live Valve at Home?
Fox says that at present only OEM bike makers and Fox service centers can re-program Live Valve's timing algorithms using a PC up-link. This is necessary to customize the system to match various suspension kinematics, and applications. There is the possibility that users could be given this power in the future, but as of now, Fox is taking a conservative approach as it releases the concept into the wild - at least for the first year.
Fox is still working out the details, but their plan is to give key retailers and service centers the technology to custom tune Live Valve suspension and later, offer a variety of plug-and-play pre-programmed tuning maps directly to consumers. Fox furnished me with a PC loaded with Live Valve software and walked me through the programming process. It was intuitive to use and the effects on the bike's performance were tangible.
Do Live Valve Shocks and Forks Need Special Tunes?
Fox encourages riders to set their suspension exactly how they like it. There is no need to change your air pressure, sag, or rebound damping to adapt to Live Valve. That said, the full-time pedaling action affords riders the option to choose a more gravity oriented tune without paying a penalty elsewhere on the mountain.
Fox says that both wireless options and Shimano's Di2 electronics were too slow to meet Live Valve's reaction times. Wires exit from the lower face of the Controller module, directly into the frame tube. Fox Image
Is Live Valve Compatible With Other Systems?
Fox investigated a number of options, including compatibility with Shimano Di2, and wireless actuation (like Bluetooth), but none of them had fast enough response times. In the end, Fox had to develop their own electronics from scratch. The decision to develop Live Valve from the ground up paid dividends in many areas of its development. Live Valve's latching solenoid valve, for instance, uses permanent magnets to retain the needle valve in position. To open or close the damping circuit, an impulse signal momentarily disarms the magnet - after which, the valve requires no additional current to remain in position. Similarly, Fox's electronic team were free to develop algorithms specific to Live Valve. As a result, the system is deceptively simple and draws little from its battery.
Evolutionary steps: Fox developed and perfected its electronics in-house. RC photo
What about battery life?
Fox estimates Live Valve's run time on a fully charged battery at 16 to 20 hours. The two-cell 7.4-volt Lithium Ion battery is essentially the same as the one Shimano uses for its Di2 shifting, although the two systems are not interchangeable. Recharge is via a USB cable and this can be done while the battery is on or off the bike. The battery has a quick-disconnect feature and is sealed (like the entire Live Valve system) against the elements to IPX7 standards.. Charge times are in the neighborhood of 1.5 hours, but if you forget, a 15-minute charge will get you through a two-hour ride.
Low battery default: If the battery fails or runs down, Live Valve defaults to open mode. Your descending will be optimized and at worst, you'll have to pedal home with your suspension in soft mode. That shouldn't be a deal breaker.
The Controller's battery can be removed or charged on the bike. Waterproof seals are used at every junction.
Which Forks and Shocks Will be Compatible?
So far, all Fox forks with FIT 4 dampers are compatible with Live Valve (32 Step Cast, 34 and 36 forks). Float shocks with the dual piggyback design will be available with EVOL air sleeve in standard, metric and trunnion configurations. Fox designed the dual-chamber reservoir to flip-flop forward and back on the shock body in order to fit up with frames that have clearance issues, or to make room for water bottles.
How Much Weight Does Live Valve Add?
Comparing apples to apples, Live Valve adds 144 grams (according to Fox) when compared to a stock 2018 Scott Genius with cable-actuated remote suspension. That delta is a little inflated, because the Scott has a lighter weight in-line shock as standard equipment, while Live Valve shocks are the more-sophisticated reservoir types found on most high-performance bikes.
Live Valve Weight
• Battery: 72 grams • Controller + sensors: 104 grams • Live Valve 185x55 trunnion shock, complete unit: 466 grams (compare with similar float DPX2 @ 400 grams) • Live Valve fork damper adds 20 grams (36 fork, 29” wheel-size)
My review bike was a medium-sized Pivot Mach 5.5. Pivot says the up-charge for Live Valve suspension is close to $2000 USD. Ian Collins photo
How Much Will Live Valve Cost?
Live Valve will be an expensive purchase for aftermarket customers - the MSRP includes the price of a fork and shock in addition to the Live Valve electronics kit. Fox pins the aftermarket price for a Live-Valve system based upon the 36 fork at $3250 USD. But, don't freak out yet. With few exceptions, Live Valve first-adopters will be buying their systems pre-assembled on complete bikes, and will benefit from lower OEM pricing structures.
Live Valve Retail Pricing Complete Live Valve Aftermarket system includes fork, shock, and controller with wiring and sensors.
Significantly less for OEM customers: Pivot's Chris Cocalis says that the up-charge on their Mach 5.5 (which features the Fox Live Valve 36 fork) will be $2000 - still a chunk of change, but if it will make you feel better, that's equivalent to the cost of an elite-level carbon wheelset. Giant and Scott will also be offering OEM-spec Live Valve models and currently, Rocky Mountain and Niner have joined a growing list of brands that have Live Valve friendly bikes in production.
Understandably, bike makers initially will be offering Live Valve on their upper-echelon models. Giant will lead with their Shimano XTR 9100 equipped 2019 Anthem Advanced Pro 29-0 at $11,500. Scott will feature Live Valve on its top-level Genius at $9,999 USD. Fox projects aftermarket sales will begin this fall.
Ian Collins photo
I had doubts that Live Valve could manage a significant improvement in the Mach 5.5's pedaling efficiency, as it already rates at the top of the list (sans damping aids). Live Valve, however, would prove me wrong.
Fox invited PB to preview Live Valve at its new development and service facility in Asheville, North Carolina. The plan was to discuss the system with its creators and then spend a few days riding with the Fox crew on the outstanding trail network in the surrounding mountains. Fox point man Mark Jordan is well aware that a few days riding in a factory-selected environment, sequestered by their staff is not conducive to free expression and honest reporting. After the dog and pony show, they boxed up our test bikes and sent them home with us for an extended (and private) review on our home trails.
About the bikes: Giant, Scott, and Pivot furnished test bikes. My choice was Pivot's Mach 5.5, with 140 millimeters of dw-Link rear suspension and a 160-
Test bikes lined up in Fox's North Carolina service and development facility. The Polaris RZR UTV is also Live Valve suspended. Ian Collins photo
millimeter-stroke Fox 36 fork up front. I had doubts that Live Valve could manage a significant improvement in the Mach 5.5's pedaling efficiency, as it already rates at the top of the list (sans damping aids). Live Valve, however, would prove me wrong.
Charging Live Valve can be done on or off the bike. Just pop open a waterproof cap and plug in the micro USB cable. Two hours later, you're good to go for a week or more of riding. Two clips retain the battery module, which is sealed from the elements by an O-ring and Fox provides a doppelganger cover that replaces the module to protect the internals while the battery is gone. Much like Shimano Di2 shifting, Live Valve's battery lasts so long that you'll probably forget to charge it at least once.
The USB charging port is also used for programming. RC photo
Break-away connectors provide crash protection. RC photo
Mechanically, I was prompted to set my suspension exactly to my previous preferences, If you're interested, that's 20% sag up front and 30% sag out back, with a few clicks of low-speed compression damping and with my low-speed rebound straddling the midpoint - a little too fast to tame G-outs at a slow trail pace and just fast enough to take the edge off of baby head rock gardens and roots on the downs. How many clicks that is would depend upon whether I am riding in North Carolina or Southern California.
Push the on-button, choose your threshold setting, and then Live valve takes care of the rest. I chose the number two option, which remains my favorite to this day. Initially, there are few sensations that signal Live Valve is at work. The latching valves make tiny clicking noises, so you'll know that something is going on down there, but the system responds so quickly that the hand-off between open and closed feels seamless. I was lulled into believing that nothing was going on until I realized that every root and rock that I was rolling over on my way up the mountain felt like it was the same size. They weren't.
Climbing was exceptional. The transition between open and closed was seamless under power. Ian Collins photo
G-limited: Live Valve opens when G-forces hit its preset threshold with such precision that all initial impacts feel about the same. I was banging into an array of rocks and roots ranging in size up to five inches, but at the grips, my 36 fork's four-G threshold setting made the bike feel like I was rolling over a continuous web of small, two-inch-diameter (50mm) roots. Adjust the G-force threshold up or down (Fox let me experiment with Live Valve settings), and you'll feel a proportionate change in the bike's small-bump sensitivity. After Live Valve's latching solenoids open, however, the quality of your suspension is entirely dictated by your air-pressure and damping choices, and the bike's kinematics. Or is it?
When climbing, the fork and shock respond independently. The rear suspension doesn't settle when it gets steep and rough. Ian Collins photo
Improved suspension action: One might assume that, because Live valve can only toggle a percentage of your shock and fork's low-speed compression damping, that it could not significantly improve the performance of your suspension outside of its pedaling feel. Live Valve's timing algorithms, however, greatly enhance the way the suspension responds while climbing. Live Valve manages to maintain the bike's ride height, so beyond the actual grade of the trail, there was never a perceptible change in the fore/aft balance of the suspension and its ride height as I made transitions from flat to climbing.
It took a while before I stopped pausing momentarily to transfer my saddle position forwards at the onset of every climb. That was no longer a necessity. The only times I needed to break my pedaling cadence and move my weight around on the saddle was for more technical ascents or steep, punchy climbs - and even then, the stability the system added to my already sharp climbing Mach 5.5 was remarkable. I also could pedal more smoothly up chunky section because the controller allows the fork and shock to respond independently in climb mode, which keeps the rear wheel driving, and the front of the bike tracking, instead of skipping over the chunder.
Ian Collins photo
Another surprising improvement to the suspension's action was the 'free-fall' mode. I never realized how often I was airborne while riding at pace over relatively smooth trails until I started using Live Valve. The controller can sense and react to a tiny drop, which dramatically smooths the medium-sized G-outs that most perceive as bothersome trail chatter. My bike felt more glued to the ground at speed. Corner entries and hard braking felt more precise.
The Live Valve litmus test occurs when you switch it off (or run out of juice in the battery, as I did once). Every time I switched off the system for back-to-back comparison runs, it only took a minute or so before I wanted to pull over and turn it back on. Live Valve defaults to open mode, which still provided sprite pedaling action aboard the Mach 5.5, but once you know something you can't un-know it.
Can You Live Without It?
Live Valve is going to find its home on high-performance trail bikes with generous amounts of wheel travel that are owned by enthusiast-level riders who already own a high-end machine and want a better bike for their next purchase. There are a handful of trail bikes presently available that pedal efficiently without suspension aids and Pivot's Mach 5.5 is among them. No, you don't need Live Valve to ride at the highest level, but if you have the money to burn, you'll get more performance for your dollar from Live Valve than you could hope to squeeze from electric shifting, a fancy carbon wheelset or even a sequential-shifting gearbox.
What I Liked Most
Simple pleasure, perhaps, but my favorite aspect of Live Valve is never having to pause at the top of a climb to check if my suspension is open. Or checking my suspension at all, for that matter. Down, up, flat, rough, or smooth, my suspension is always doing what I want it to do.
I have often written how I like to keep my suspension wide open all the time - primarily because I have hit so many downs with my climb switch accidentally left on firm that I'd rather enjoy the climbs a little less in return for the assurance that I'll be ready for every descent. Well, Live Valve lets me enjoy the whole ride without thinking about my suspension - and that makes me a happier, and a measurably faster rider.
Ian Collins photo
Live Valve Can't Fix Stupid
What Live Valve can't do is compensate for a poorly set up fork or shock. If your suspension is pumped up to a zillion PSI and plugged with air-volume spacers, or if your dials are screwed to their maximum positions, you are on your own. Live Valve will happily toggle your low-speed compression circuits at precisely the right moments, but at best, your ride quality will only be less worse. Live Valve turns in its best performance when the suspension is biased to enhance traction and match the rider's technical skill-set.
Fox was right to wait until Live Valve was thoroughly proven before they released it. I imagined that I'd be concluding with a carefully scripted paragraph that weighed its astronomical retail price against its potential benefits. The bottom line is that Live Valve represents the most useful and important suspension innovation to emerge during a decade of boring gradual improvements. It works great, and I don't want to ride without it.—RC
Getting sideways at the Fox test track. Live valve first debuted on Polaris RZR UTVs under the name "Dynamix." Ian Collins photo