RockShox's just-released Flight Attendant system automatically adjusts your bike's suspension as you ride, using sensors and motors to quickly add or subtract compression damping on your fork and shock, all without you having to reach down to flip a pedal-assist switch. More importantly, it automatically cycles through Open, Pedal, and Lock modes depending on what you need at that moment, while also offering a new level of tuning, called Bias Adjust, that might make your long-travel bike far more versatile.
Oh, and the entire thing is wireless, powered by the same AXS batteries as SRAM's electronic drivetrain.
Fight Attendant Details• Intended use: 130-170mm of travel
• Auto adjusts fork and shock's compression damping
• Manual adjust low-speed rebound, Bias
• Wireless, uses AXS batteries
• Availability: OE only (for now)
• Weight: approx +300-grams vs equivalent non-Flight Attendant system
• MSRP: TBD
•
www.rockshox.com As you might imagine, there's a lot to talk about with Flight Attendant. We'll cover the basic details and questions below, and you can check out Mike Kazimer's
full-length review for all the riding impressions.
What is it and what's it for?The whole idea behind Flight Attendant is simple: make your mountain bike pedal better while still prioritizing the downhills. RockShox's approach is simple, too: add compression damping to make that happen. You know, just like those pedal-assist levers that you see on pretty much every shock on the market, only you don't have to think about flipping a lever at all. Instead, sensors on your bike tell the fork and shock to do it automatically, which is when small motors run through small gearboxes to ramp up the low-speed compression damping. And that makes a big difference on the trail.
We suspected that SRAM was working on some sort of AXS-powered suspension system way back
when their wireless drivetrain was first released in February of 2019. While I was shifting gears at that press camp in Tucson, Arizona, their development riders were on nearby trails testing prototypes. They did their best to avoid us, unfortunately for me, and SRAM did their best to dodge any questions that weren't about their drivetrain. I found myself at SRAM's North Vancouver office shortly after that trip and spotted the phrase 'Flight Attendant' written in massive red letters on their whiteboard, but that was back then we thought it was a relatively simple wireless lockout with maybe some sort of integration with the drivetrain or dropper post, and probably aimed at the short-travel Lycra crowd.
However, Flight Attendant appears to be far more useful than a lockout switch, and it's been designed with enduro and trail bikes in mind.
What are the Flight Attendant components, and how does it work?Flight Attendant consists of three important components, but I should mention straight away that they're mounted to an essentially normal fork and shock. The Pike, Lyrik, and Zeb Ultimate, as well as the Super Deluxe Ultimate shock, all have normal internals, normal damping circuits, and aside from the funny-looking LED-equipped growths hanging off them, are both standard items. Does that mean you'll eventually be able to convert your current RockShox boingers to use Flight Attendant? Maybe way down the road, but it's not happening anytime soon.
The three main Flight Attendant components are the Control Module on the fork (pictured above), the Motor Module on the shock, and a pedal sensor that slips into your crank spindle. You need all three to use the system, which means that you can't run just a Flight Attendant fork or just the shock - they function only as a team.
The Control Module on the fork is the brain of the entire system, and it's what tells both the fork and the shock to firm up or go soft. There's an accelerometer and gyro hidden in this little unit (as well as in the shock) and, along with the pedal sensor, it's how it knows what your bike is doing so it can tell the suspension what to do. The sensors know if you're pedaling or coasting, if you're upright or leaning over mid-turn, if the bike is angled up, down, on flat ground, or if you're in the air, and adjusts the compression damping accordingly. The pedal sensor is especially important to the system, I was told, as it's what allows Flight Attendant to predict what's happening rather than just reacting, but it'll only fit into DUB spindles as of right now.
Picture this: you're descending on your enduro bike and everything is normal, with the suspension wide open and able to do its thing. All of a sudden, you're faced with a short, steep climb that's trying to ruin your fun. As soon as your bike's sensors know that it's pointing up a hill and you're on the gas, the Control Module sends an order to both the fork and shock to stiffen up so it doesn't feel like you're trying to double bounce a stationary bike on a trampoline. At that moment, the little motors spin at roughly a million RPM, which is then put through tiny gearboxes (just like on an AXS derailleur) to simply turn the compression rod to firm up your bike. Notably, you can adjust how often that happens via the important Bias Adjust that we'll get to in a bit.
When the bike senses that you're back to the fun part of the ride, it opens the fork and shock's compression back up to where you want it. It's probably important to mention that your rebound damping will always be unaffected - it's a manual adjustment that doesn't change because that'd be really scary.
Flight Attendant forks and shocks are essentially normal units but with the Control and Motor Modules attached to them. That means they can be worked on as per usual, be it some quick love in the garage or deeper maintenance.
But how does it know to do all that? ''
Flight Attendant’s algorithm is highly sophisticated and born from thousands of hours of rider input and data analysis,'' RockShox says, and it's all hidden in the Control Module's brain on top of the fork. There's also a fundamental difference between this and Fox's older Live Valve system (aside from this being wireless), with Fox favoring pedaling efficiency while, according to RockShox, ''
Flight Attendant’s highest priority is adjusting the system to the open position when bumps or disturbances are detected and will adjust the system to be more efficient when it senses the rider pedaling.''
Is it adjustable?Flight Attendant-equipped forks and shocks are both more and less adjustable thanks to them losing the external high-speed compression dial (it's now non-adjustable) but gaining something called Bias Adjust that's a super integral part of how the system performs.
First, your normal low-speed rebound adjustment dials are still where you expect them to be, at the bottom of the fork leg and top of the shock. Nothing has changed there. But what you won't find is a dial for low-speed compression; that's adjusted via buttons on the top of the Control Module that controls both the fork and shock. Yup, you now adjust the shock's compression damping at the fork by toggling between the two. And because the future is apparently now, you can also make the same adjustments via the AXS app, if you're into that kinda thing. Different colored LEDs on the module also tell you what you're changing and by how much.
Bias Adjust is the new tuning feature, and it's also changed either on the Control Module or in the AXS app.
RockShox has a long-winded explanation about Bias Adjust, but the gist of it is this: more Bias means that your bike will feel firmer and more efficient more often, while less Bias means it'll stay open and pedal like a gooey enduro bike more often. An obvious example of where this might be useful would be a rider who's taking their enduro bike to a relatively smooth, flowy network of trails. They might want to add a click or two (of five in total) of Bias Adjustment to bring more life and momentum to their bike. A rider who spends more time on rooty, rough, complicated trails, or if traction is low, might want less Bias so their bike is more active, more often.
RockShox says that running it in the middle setting provides, "
an effective balance of all three suspension positions,'' and that there's, ''
no right or wrong, Bias Adjust is all about choice and fine-tuning the feel of the system to better match your ride style.'' Adjusting it takes only a few seconds by pressing a button on the Control Module.
Depending on your Bias setting, those three modes - Open, Pedal, and Lock - are constantly being cycled through while you ride in Auto Mode, but they can also be chosen manually if you decide to not let the robots do the thinking for you. That gives you the ability to choose which mode you want by pressing a button on the fork's Control Module or your chosen paddle on your left-side AXS shifter. You can always open, firm up, or lockout your suspension at the push of a button if you'd rather decide than let the computer do it. There's also an Override Mode that, at the push of a button on your shifter, can revert to a preferred suspension setting - pretty neat.
Speaking of settings,
Kazimer's review of Flight Attendant also shows you how to pair and set the system up from scratch. You only need to do this five-minute process once, unless you make notable geometry or travel changes to your bike.
Really, more batteries and apps?Hey, at least it's wireless. Flight Attendant requires two of the same AXS batteries used for the derailleur, with one attached to the Control Module on the fork and the other powering the Motor Module on the shock. RockShox says to expect 20 to 30 hours of battery life for the former, and 30 to 40 for the latter. The pedal sensor (that only fits DUB spindles for now, but that might change) is powered by a AAA lithium battery that should last for around 200 hours, so you won't need to think about that one until it dies in the middle of nowhere.
Don't forget that if that happens the suspension reverts to full-open mode rather than some terrible firm setting.
If you're like me and the thought of using an app to do anything other than find the closest Tim Hortons makes you groan, the good news is that you definitely don't need to. All of the setup and adjustments can be done without using your phone, but the AXS app does let you customize controls, get a better idea of the remaining battery life, and do any firmware updates. You can also tweak compression and Bias for the fork and shock via the app, which is a neat and maybe-sometimes handy trick, but I suspect most would rather leave their phones alone.
Where can you find this stuff? How much will it cost?Not for sale in your bike shop anytime soon, that's for sure. You see how the Control Module hangs off the back of the fork, and how much larger the shock is thanks to the Motor Module? Because more downtube and shock clearance is required, there are bikes that Flight Attendant won't fit. Factor in the already long lead times and you can see why RockShox couldn't give me a date for aftermarket sales. I don't have any aftermarket costs for you at this point, either, but you know how an AXS derailleur costs a lot more than a normal one? Yeah, think along those lines and you probably won't be too shocked when you see the price tag.
The only brands currently selling Flight Attendant-equipped bikes are Specialized, Trek, Canyon, and YT, but that'll change down the road.
For this year, you'll only
find Flight Attendant on a grand total of six bikes spread across four brands - Trek, Specialized, Canyon, and YT - with travel ranging from 130mm up to 170mm. It's probably safe to assume those will be expensive bikes... The Specialized S-Works Enduro that Kazimer tested Flight Attendant on will retail for $12,500 USD, or $2,000 more than the version without smart suspension, so that gives you an idea of what to expect.
What do I think?I hate computers, and my level of technical expertise when it comes to this kinda stuff can be summed up with, ''
Unplug the router, wait ten seconds, then plug it back in.'' Sometimes, I think it's the wifi that's making me itchy. Furthermore, it's almost a certainty that anything battery-powered I touch stops working soon after, usually in the acrid smoke of an electrical fire. So yeah, I'm naturally wary of anything with a circuit board for valid reasons. I'm a fan of the AXS drivetrain, sure, but this is
different, isn't it? This is doing something on its own...
But it also was completely invisible during the single, 3,000-foot descent that I used it on. The Flight Attendant-equipped Enduro felt as capable and competent as our long-term Enduro test bike that we've all put countless hours on. That is until I had to pedal it up anything, which is when it acted like it had about 140mm-ish of firm suspension travel. More importantly (and impressively) was how it transitions seamlessly between the different modes on rolling sections of trail, adding some pep to the usually soft-feeling Enduro as needed.
If you're looking for a proper review and more feedback,
Mike Kazimer has a month of riding on the same bike and you can read his thoughts on the homepage right now. As for me, I'm impressed and have yet to unplug the router.
'RockShox's just-released Flight Attendant system automatically adjusts your bike's suspension as you ride, using sensors and motors to quickly add or subtract compression damping on your fork and shock, all without you having to reach down to flip a pedal-assist switch."
I am not an electrical engineer, but sounds like the system needs electrical current to function, and an ebike main battery provides that current. They'd probably need to figure out the correct voltage, etc....but seems like a surmountable problem.
Oh and to think how bicycles were such Pure elegance simple, quiet, light, near perfect.
I must be fing old.
(I would love to try it though)
You say that as if supply chain issues aren’t a real thing.
They very much are.
the supply chain issues are bad and prob gonna get worse before they get worse.
www.specialized.com/ca/en/s-works-turbo-kenevo-sl/p/199107?color=318020-199107
“Springing the shocking price tag.”
Nice work, I see what you did there…
went to In-n-out yesterday for the first time in a year. double-double went from $4.25 to $5.25. that's 23% inflation. looked at a new motorcycle. same bike, no changes other than colors. price is up 18% from this time last year.
I don't know why people think bicycles are some how immune to government money printing. SMH
It does seem like it could allow a bike designer to setup a bike for plush and crush without worrying about pedal inefficiencies. Unfortunately, anyone not spending the cash on the electric shock version would end up with a bobbing machine without a whole bunch of compression damping.
So RS, what I would by is a suspension with proper range of adjustment on which rebound does not increase low speed compression (you know, this check valve thing you add over the shimstack ...)
Derp
And we don’t all have have a 37lb bike with DD tyres and inserts but if you do it makes your 3/4lb comparison even more ridiculous.
People have tried to test many times, but I have yet to see any convincing evidence that lockout switches at all meaningfully impact climbing times for modern bikes.
Finally, this is just an automatic lockout. The only fancy thing about it is the "middle" position.
Is that less or more than "1 pound"?
Your own point is still ridiculous, this systems extra weight on a bike weighing 35lb plus will be negligible compared to the performance advantage, even if you are a luddite and won’t accept it’s not then just a ‘lockout’
However, regarding electronics, yes in Moto gp. Not mx and enduro. However, mx/ enduro suspension is infinitely more adjustable through the valving and clickers. Hence why I run a coil shock and coil cartridge on my DH and trail bike. Just feels like home.
blog.ktm.com/ktm-1290-super-adventure-semi-active-suspension-from-wp
Will be interesting to see if it makes it over to the enduro world. Maybe there's just not enough of an advantage to make it worthwhile.
beauty in the eye of the beholder i guess
@mikelevy: That's true, there would be a substantially more packaging issues considering the size a weight targets they are likely going for. Just don't get me started on tires, why a premium summer tire costs only 3 times what a premium bike tire does still blows me away.
This is why I love 17” wheels. My last set of pilot sport 4s’s cost just shy of $1k installed and aligned.
Look at the similarities:
www.neebu.net/~khuon/cycling/bikes/K2/1999-OzM/smartshock.html
products.mtbr.com/product/older-categories-bikes/front-shock/k2-bike/smart-fork.html
Whatever. Either way, that LP system worked well and I'm sure this is even better. You could completely blow it in a corner and then "zzzt" pedal out through roots or whatever with your suspension all firmed up. The only drawback I found was forgetting to use a lever if I wasn't on the LP. The battery took up water bottle space but we were still wearing packs...and actually the first lipstick battery housing let water in...but still: it worked, it worked well, and this does the same but cleaner. I can dig it, for those still holding on to OPTIMIZING PEDALING PERFORMANCE over ROASTING LAPS ON OUR HORST LINK EBIKES
(you fools)
Seems like the only compatibility issue with the crank sensor is the end with the cap and o-ring. The other side is an expanding plug. I agree they could have made it more adaptable (different caps for different axles), but I'm not surprised SRAM would do this. In the video there's a photo of a bar mounted controller. I wonder if they tried what you propose.
And build sick analog hardtails and jump tons.
For where I live and the trails i find myself on, this will be brilliant. Then I’ll go ride jumps and xc loops on my old crusty bikes too.
All the bikes.
And a moto.
"a discussion about performance would be much more interesting, even in the article that is very lacking" - That's because it says "First Look" in big letters at the top of this article. Here's Kazimer's review of the system: www.pinkbike.com/news/review-rockshox-flight-attendant.html
"Also loosely mentioning the motor rpm is a completely misleading metric and is marketing wank. We need adjustments per second and times from fully open to fully closed." - I agree, but this was a tricky number to get from them. Regardless of the actual number, it's seamless feeling on the trail and acts like normal suspension on the downhills.
About the tricky numbers... tell me how many turns of compression the damper has and I can calculate open to closed times from the video of the motor spinning, assuming it has the same speed under load.
#1 This is how you over engineer things. Complex electronics and small mechanical gearsets is never a good idea in rough and dirty conditions.
#2 Never buy the first of something. It seldom works correctly or for long & they usually already have the better option being made. Next year they will have the set that keeps a graph of your cycles. Like Ford, next year you can buy the Raptor Bronco.
#3 it only adjusts low speed compression, isn't that wat the little lever does? This is definitely for the techy.
Yes, in the example in the post, you won't be able to reach down and change low-speed compression settings when you encounter a steep climb suddenly. But you also don't need to. The only time you really need to change compression is on long climbs, which you can do any old time on your own.
I love seeing R&D and new ideas on mountain biking, but this is solving a problem almost no one really has. Magnetorheological in mountain biking, on the other hand, would be epic.
FA reverts to being fully "analog" and normal when descending, whereas those mag dampers firm up when the car is driven hard; the opposite approach. I don't want my suspension changing on the descents, though.
I'd argue on a descent, current suspension is challenged by the fact that we want the systems open for technical features, but firmer for berms, brake diving, etc. Currently the suspension is always in some state of compromise, although the best four-way dampers tend to do a pretty solid job.
My point is, FA is just doing something relatively simple for a lot of extra cost. I get people will pay for it, I just don't know why. I'm all for having options so not trying to dump on new cool tech, this one just again seems like it's solving a very low-priority problem.
It would be neat if it firmed up for berms, brake dive, etc, but this is more of a smart pedaling aid than a descending aid. I'm not sure if I'd want my compression to change during the descent in the same way that a track car's suspension firms up as needed, but maybe there's something to that?
ten year secret: Fox has that but has deemed it too expensive.
This is just pointless complication for a simple adjustment that doesn't require this level of complexity. It's an out dated idea that has been tried several times in the past. Classic RS solving non-existent problems for the sake of marketing. The "ecosystem" is a great lesson learned from Apple.
Outside+ PRO comes with a full body electronic nerve control suit, you don't even have to do anything, the suit controls your body for you, the ultimate outdoors experience.
Also, this makes me want to get a ruly rigid bike, maybe singlespeed.
Why is this not just a climb switch? Because the system is constantly adjusting the compression as needed, which isn't going to be a useful trick if your riding is all up and then all down; of course a climb switch makes sense for that. But if you ride a long-travel bike on rolling trails, FA does what a climb switch never could... unless you want to hit that switch every few seconds or minutes? Expensive? f*ck yes. A climb switch? Hell no.
I guess you're right- spending 1000 or whatever dollars on this is almost definitely a better use of money than upgrading from SLX or especially XT to XTR. It's a bit disconcerting to see bikes get batteries and telephones added onto them- I get on my bike to get away from devices, not to keep using them- but then, bikes are exploding with springs, dampers, levers, etc. anyways; complexity and the money that buys it are the price of higher performance. They do take away to an extent the feeling of riding a bike, though.
edit: read Kaz's review - fork has new internals, probably need an entirely new fork
Does it work with SD Coil shock? You mentioned that RC2 Damper was redesigned to work with this, so does the fork still have adjustable HSC? The Live Valve is kinda crap as it is based on FIT damper instead of the GRIP2 which is far superior. Your review of the Giant Trance X clearly mentioned this, the Live Valve suspension in open mode is just not good enough thanks to that inferior damper.
I'm definitely interested. was looking for live valve for some time, but the cables and frame specific issues held me back. for me, big plus are the clean looks and no wires, next to the "smart" suspension of course. depending on functionality, i'd look for the manual lever as well, simply to switch it on or off. but if the suspension is really smart, that might be not needed.
bummer that they do not offer to link it to existing cadence sensors that might be on the bike (power meter or stand alone), that would save the weight for the pedal sensor.
i also wonder how thorough the tuning is that one can do through the app. i could imagine that it is more versatile than analog suspension setup and if you want, you can completely nerd out on multi dimensional settings (not only compression/rebound, but also add up/down riding and pedal yes/no in the equation
last question: can i likely upgrade my analog fork/shock with this stuff?
i'm not a dentist
I certainly respect and appreciate what’s been developed but I’m a little confused…. Isn’t Levy famously anti-climb switch? If so why not critique the purpose of this for that same reason? That is if a bike is properly sorted why does it need this electronic nanny? [serious]
Me, I have no problem with climb switches. I use mine regularly - not because my bike kinematics suck or because I’m unable to set my suspension up correctly - but because 99% of my rides begin with significant and steep climbs on relative mellow terrain.
Epost ? maybe ,cadence power sensors ? for pro´s
This Flight Attendant can be nice if you have the money ...how mutch ? Steve Jobs suspense and you have thousands wanting it no matter the price.They must have it ,point.
But I'm still super excited to see how much better the Ohlins system will be. That'll practically turn my 40 year old sack of bones into a balding, grumpy, less charismatic Bruni!
Those buttercups also look like a really good addition. Hopefully they'll do a retro-fit option like they did with the c1 air spring
Also would be great to be integrated with that telemetry gadget
The OP wishes it would adjust the LSC independently of the 3 position platform adjust.
I still don't understand the need for a front end lockout but that's just me.
Why can’t our bikes push boundaries in technology. The option for analog bikes or ‘62 VW beetles will always be there.
I would try this technology any day if I had the money.
(yes, username checks out… and yes it’s a SS)
idriders.com/proflex/resources/99_smart_fork_addendum.pdf
Also, if you ask most experienced tuners, they'll tell you that compression damping is actually quite different than a corresponding increase in spring rate - in some cases higher compression can behave like a softer spring (settling the bike more) whereas actually increasing the spring rate will make the bike more "poppy". They'll both have the effect of keeping your bike up in the stroke more of course, but there are as many differences as similarities.
With a fully on-the-fly adjustable *system* (versus just compression damping), you could add a motor to change the spring curve by expanding or contracting the air chamber size (akin to adding/removing tokens) and change both compression and rebound damping to optimize the return to the sag point based on the conditions you're riding (speed, size of hits, etc). Sensors could easily detect overshoot or packing up and adjust accordingly.
The technology is slowly coming...better late than never
What ski walls are on that ? Butcher ?