A recent Fox wireless dropper post patent application takes smart mountain bike technology to a new level of integration. Envisioning a world where almost everything on your bike is electronically controlled, Fox is working on a wireless dropper post that connects to their next-gen Live Valve suspension, syncs to your electronic-shift drivetrain, pairs to all the existing sensors on your bike & body, and even adds a few more new ones, too. The end goal seems to be multi-system automation – whether linked to GPS position data, to your live power output and heartrate levels, or even reacting to your voice commands…
Plus, this new dropper would add smart user-customizable drop point, in addition to classic infinite-adjust drops!
A smart Fox Wireless Dropper in development for years
We’ve seen Fox’s wireless dropper seatpost patent applications for more than a decade (the earliest one I remember dated back to 2013). And the core concept and visuals haven’t really changed at all since then – a dropper post that could be mechanically or electronically actuated, and potentially linked to multiple systems on your bike. But in those 10+ years, what has really changed is more and more electronics on mountain bikes, smarter control systems, and more possibilities for integrated and automated controls.
Some of the wildest controls that Fox could come up, now seem much more plausible in our minds – like a voice-activated dropper post or even a dropper that learns from past rides and automatically drops your saddle as you approach a descent.
So what do we know?
This newest Fox wireless dropper patent that they filed earlier this year (and was just published this summer US20240182131A1) interestingly focuses more on automatic shifting than it does on the dropper itself. But Fox’s core wireless dropper tech already received patent protection in February of this year. That simply shows a dropper with an electronic solenoid (365) inside the base to open and close the valves that allow the dropper to go up and down. It shows possible antennas (1402A&B) at the dropper collar & seatpost head to communicate with a remote, and power connectors (1404A&B) that can draw power from internal or external batteries.
What I think this suggests? Fox’s upcoming wireless dropper post is pretty much dialed-in. And now they dive deeper into the automated controls themselves.
Infinite AND stepped drops
What’s unique that we know about the wireless dropper from these patent filings is that Fox is proposing a dropper post that is both infinitely adjustable and able to be dropped to set heights. The interesting thing there, is that the tech to have infinite & stepped drops is not specific to electronic droppers, but could work on a mechanical dropper post too. That’s because they have two separate pairs of valves and release circuits inside to activate either mode (see 530 A&B and 535 A&B in Fig. 10-13, below). So the 2 modes could be controlled separately with two levers, a single 2-stage lever, or with sequential inputs to an electronic lever.
Especially on an electronic dropper, thanks to an internal position sensor the rider could pre-program their ideal drop points. Maybe you like your post fully extended for climbing but just 2cm dropped for rolling trails? Even pre-setting upper and lower stops could allow a bike manufacturer or the end user to limit overall travel, or limit full top-out height. For example, the end-user could set their saddle height with an electronic stop. And they could set how far they want to post to go down at maximum drop. That would even allow manufacturers to put the same maximum length dropper in all bikes, regardless of size, and still let the buyer easily customize their ideal position on the bike.
Inside this wireless dropper post, the Fox patent also describes how the position sensors pair to electronic actuators to feather the 4 valves that open & close to allow vertical dropper movement. That lets them slow the dropper as it reaches the desired travel set-point for smoother movement and accurate stops at any point in the travel. So no top-out or bottom-out clunks… or overshooting the preset travel limits.
Dropper paired to everything electronic
A big part of the latest Fox Live Valve patent that we reported on last year, was how much more connected it plans to be. And how smarter also means more active. Now, we expect the upcoming Fox wireless dropper post is going to get in on the smart party, too. These latest patent docs described a dropper closely synced with electronic shifting and electronic suspension damping controllers.
And automated controls seem to be their biggest feature. However don’t worry, there’s clear description of on-the-fly adjustability and a temporary pause in automatic controls whenever the rider makes a manual override input. But it looks like Fox envisions dropper post position, suspension compression damping (and somehow spring rate), and gear selection – all automatically controlled.
And automated Fox wireless dropper control from all sensors
The Fox solution sees a central processing unit and controller collecting data from speed, cadence, power meter, rider heart rate, GPS location, vertical acceleration, and inclination sensors. And crunching that data to make sure your bike is always in the optimal setting. They also describe a voice activation system where you could speak commands to drop or raise your saddle to a predetermined height, of drop/raise it fully. And there’s descriptions of a screen, indicator LEDs, or even audible alerts (beeps?) that could confirm what mode or position your dropper post is in.
“…the seat post is actuated by a controller designed for receiving and analyzing input associated with a cyclist’s heart rate as well as the cyclist’s GPS coordinates. For example, if the controller receives input that describes the cyclist’s heart rate as being lower than a given preprogrammed threshold while riding, then the controller may signal to the seat post to move up or down, causing the cyclist’s work rate and heart rate to increase or decrease. In another example, if the controller receives input that describes the cyclist’s GPS coordinates as being such that the cyclist is just about to arrive at terrain having a steep descent, the controller may cause the seat post to lower in preparation for the descent.
…[or] following a pre-mapped route, for example, predetermined seat post height and/or gear selections, or suspension settings can be embedded in the route map and the controller can signal the seat post height changer and gear changer to change to the location appropriate seat post height and/or shift to the location appropriate gear automatically.”
To us this all sounds pretty wild.
But, Fox has been working on much of this tech since at least 2012 – before XTR took mountain bikes electronic with Di2 in 2014, long before SRAM pushed MTB wireless with AXS in 2019, or when Fox made Live Valve electronic suspension controls real the summer earlier.
So maybe it’s not as far-fetched as it sounds?
