Cross-Country Tech - Vallnord XC World Cup 2017

Jul 1, 2017
by Mike Levy  
Kate Courtney s Specialized Epic.


Specialized just released the 2018 Epic, a 100mm-travel all-out cross-country race bike, so it was no surprise to see Kate Courtney aboard the new machine in Andorra, shot here by Pinkbike race photographer Irmo Keizer. Gone is the FSR design, with the rear axle pivots now replaced by a flex-stay system that's said to shave 240-grams on its own, or a weight saving of approximately 39% over the previous model. The top drawer S-Works frame is claimed to be a whopping 345-grams lighter than the 2017 version, with the total weight coming in at 1,900-grams for a medium with a shock. Geometry has also been updated - there's a longer reach paired with a shorter stem, and they've gone with a shorter, 42mm offset fork. The goal was added stability but without taking away from the nimbleness that cross-country bikes are known for.

bigquotesIt rides a little bit more like a trail bike. They changed the geometry, especially in comparison to the Era. As soon as I got used to it, it is a lot more stable descending. As soon as you get your weight in the right place, it is also a lot more stable around corners. That is a huge advantage on this course in Andorra with all the slick roots and rocks here. All the geometry changes and the updated Brain have really improved the performance.

This week is the first time I've ridden the bike. It is always challenging to get on new equipment and getting it dialed in. Luckily my mechanic Brad and I have worked together for over three years; he really knows how I like my ride to feel. He was able to get my suspension to feel like it did on the era. He also made some other changes to get it to where it is now. One of the biggest challenges with a new bike is to get used to the new center of gravity. The dropper post for this race helps me as I do not have to worry about the seat and navigating around it. I can put my body where it provides most stability.

At first, I was a bit skeptical with the short stem and tried a longer stem, but I settled on the 60mm one. My position on the bike is almost identical to what it was on the era. I feel confident as I feel I am not making huge changes mid season yet gain performance and handling.
Kate Courtney


Vallnord XC World Cup 2017
Vallnord XC World Cup 2017
Courtney's Epic is rocking a 60mm stem and a party post, albeit a short-travel one.


Vallnord XC World Cup 2017
Stopping power is provided by Magura s MT8s.
The new Epic employs an equally new shock and Brain setup that's bolted to the disc-side dropout.




Raphael Auclair s Pivot Mach 429SL. Enve M60 rims with DT Swiss 240S hubs Shimano XTR Di2 shifting a Rotor REX-1 crank with noQ non-oval ring and Enve stem bar and seatpost.


Something tells me that Raphael Auclair is a fan of carbon and electronics. His 100mm-travel Pivot Mach 429SL is a tech dork's dream, with carbon rims and cockpit from ENVE, and Fox's iRD electronic lockout that allows the compression settings of the fork and shock to be changed at the same time with a handlebar mounted remote. Raphael is also running Shimano's XTR Di2 setup, or at least the rear derailleur, shifter, and required electronics. The front of his drivetrain is a Rotor REX-1 crank with noQ non-oval ring, and there's also a tidy chain guide from Paul Components that acts as extra insurance.


Electronic lockout running of the Di2 battery.
Vallnord XC World Cup 2017
The simple and classy looking Paul Components Chain Keeper guide is the antithesis of the battery powered suspension and carbon fiber frame and components.


Vallnord XC World Cup 2017
ENVE M60 rims with Maxxis rubber.
Unlike a lot of World Cup rigs, Auclair's stem isn't slammed as low as possible. Instead, there looks to be 20mm of spacers under his stem. He's also running Maxxis' fast rolling Ikon rubber.




Reto Indergand s Fourstroke 01. Full electronic intregration of the Shimano XTR Di2 drivetrain and the Fox suspension.


More carbon fiber, more electronics, and yet another dropper post for the Vallnord cross-country course. This red rocket is Reto Indergand's BMC Fourstroke 01, another bike with Shimano's XTR Di2 drivetrain and Fox's Live Valve suspension. The dropper post is KS's LEV CI that offers 65mm of stroke and weighs around 450-grams thanks to a carbon outer tube and pared down components. The Vallnord course is no joke, and tire choice is one of the most important decisions that a racer can make; some roll the dice on mega-light rubber, while others opt for something a bit more robust. Indergand has gone with a set of Vittoria's Mezcal tires, sans tubes.


Reto runs a single chainring Shimano XTR Di2 setup with a proprietary BMC carbon chainguard. The chainrings are of a newer type as the ones the team rode last year.
Shimano XTR M9000 brakes with organic pads.
Indergand prefers organic pads for his XTR Race brakes, and he's also running a very trick carbon fiber guide that probably weighs about as much as a sheet of paper.




Axxios vibration reduction.


Did you spot that tiny silver square on the inside of the fork arch? Many World Cup cross-country and downhill racers are sticking these silver-colored squares onto different parts of their bike, and while they look like tiny GPS trackers from a spy movie, their true intention is much more interesting. They're made by Axxios Technology, a Swiss company that says that their AXS Sensor System is able to allow a rider to go faster thanks to their tiny silver stick-on squares providing a ''massive reduction of the negative impact of vibrations of the bike.'' How much faster? ''Among the best racers in the world, the improvement is 1 second per racing minute; among amateur pilots, time saved is even greater, about 2 or 3 seconds per minute.'' Those numbers are no joke when you at the level of Mathias Flückiger, whose bike is pictured here.


Axxios technology is said to provide vibration reduction by placing small metal plates on strategic places on the bike and parts. On the bike of Mathias Fl ckiger this resulted in 26 reduction data as given bij Axxios .
Vallnord XC World Cup 2017
Axxios claims that the AXS Sensors on Mathias' bike reduces vibrations by 26-percent.


Axxios says this is possible due to a series of small oscillating circuits (capacitors and inductors) inside the stick-on AXS Sensors that act as very fast access energy reservoirs. I'm going to let them explain how the system works: ''Whether in a solid, liquid or gaseous medium, the AX Sensor acts directly within the material by inducing atomic diffusion. It affects the electrical and mechanical properties of the material onto which it is bonded, by means of electromagnetic interactions. Effectively, because this material and the AXS Sensor are of different natures, a difference in contact potential is created at the interface, since the energy required to remove an electron differs between the two materials. All potential differences give rise to an electromagnetic field that affects the basic material: higher elasticity modulus, higher natural frequency, and reduction in amplitude of parasitic oscillations.''

More vibration control is said to equal less fatigue, better performing suspension, and more traction, but does it actually work? The AX Sensors are being used in motorsport, human-powered sport, and industrial fields, but I'd have to try it myself before becoming a believer.

Author Info:
mikelevy avatar

Member since Oct 18, 2005
2,032 articles

154 Comments
  • 229 2
 AX Sensors seem like snake oil.
  • 79 1
 Are they gluten free?
  • 55 1
 Agreed. Word salad with snake oil dressing.
  • 32 1
 I remember those stick-on cell phone antennas that increase reception. Total hoax...

But I guess since AX "affects the electrical and mechanical properties of the material onto which it is bonded, by means of electromagnetic interactions", it's gotta work, right? Ha ha...
  • 38 1
 Time to bring back Power Balance.
  • 5 2
 @Jimmy0: Are they Kosher?
  • 7 4
 I personally have tried a dumbed down version of these little stickers by simply wrapping each frame tube with a couple wraps of thick rubber tape. I can't say the bike performed better by any means but it definitely was quieter. Bringing electron movement into the equation definitely feels like some voodoo stuff, though lol my philosophy behind the tape was the idea of interrupting vibrations through a tube
  • 62 8
 Within the first few months of use you may get some red spots of your skin, it is a sign that toxins are leaving your body and you will no longer be infected. The sensor helps with variety of veneric diseases.
  • 24 0
 They use the same tech as the hologram bracelets . Now give me your money.
  • 12 6
 Ever heard of the placebo effect? I say if they believe they're going faster then hey, just let them stick them everywhere... Just as long as the industry doesn't try and push such crap on us... Remember that time they did the same with wheel sizes?
  • 5 0
 @Spark24: vibrations are quite simple to mute/dampen with different materials, but a sticker?
You would think a bearing race made from other materials then standard steel would have a better effect then a sticker.
  • 17 4
 @enduroFactory: I am puzzled, they said that carbon is great at muting vibrations! However my theory, and I really know what I am talking about, is that they are... trolling
  • 5 2
 @enduroFactory: look up the word "placebo"... It's all in the mind... Just like that power balance bracelet rubbish
  • 5 1
 Wow, imagine how much my InvisiFrame is speeding me up! Seriously though, the world in a weird and wonderful place, maybe they do work.
  • 26 2
 Talking about changing the elasticity modulus of the material sets off all kinds of alarm bells - outside of temperature and pressure changes, a material's elastic modulus is a fundamental constant, so you'd have to literally be changing the atomic structure i.e. turning it into a different alloy/material entirely, to change it.

AXS have a lot of marketing people, but not a lot of engineers
  • 9 5
 @Smevan: there is a big chance that reciting Hail Marys can have bigger effect on your race performance since it takes focus to repeat something over and over again 52 times.
  • 72 0
 i'm a material physicist and i don't know what the HECK AX is talking about. seriously.
  • 6 8
 @Smevan: The only way I know to change the E-modulus of a material is to use piezo electricity. You indeed need to bond different metals and you could either use a circuit or not. I can't tell whether this is properly executed or even whether the concept makes sense in the first place. I'm no expert either but I do think this could possibly work. But if it does, I'd be concerned about corrosion too. Anyway, it seems like they'll have to tweak individual components and bikes, you probably can't do this in mass production. As such we shouldn't be too worried finding mismatching squares on our oh so color coordinated bikes. That said, balancing your bike and your wheels in particular makes sense. But I see no easy way now that we have all this liquid sealant in there too.
  • 4 1
 seems like those hologram bracelets that you can buy at the mall that are supposed to help you with your flexibility and health just by wearing them. But hey... maybe the placebo effect of those little squares will make them ride faster.
  • 6 1
 @WAKIdesigns: will i also be immune in a possible zombie invasion?
  • 24 0
 I know a way to change the resonant frequency of a material: Strap a weight to it. *Everyone in the XC racing pits faints*
  • 2 1
 @Spark24: agreed. Seems just like those idiotic magnetic bracelets.
  • 1 1
 Just stick a bunch of Band-Aid to your frame and there you go
  • 24 1
 i have 3 of these on my dong right now
  • 3 11
flag vinay FL (Jul 2, 2017 at 13:08) (Below Threshold)
 @WaterBear: Really? The main thing for them is to be the first to finish. If you're saving over one second per minute, that's considerable. If you can get a similar effect by tuning using some extra weight here and there it is well worth the effort. Balanced wheels may also save you from punctures and a balanced drivetrain is less likely to derail, that's worth even more. I think they look beyond weight, or they wouldn't use these large diameter wheels. And is Eagle actually lighter than a 2x drivetrain?
  • 8 0
 Their pitch sounds like utter bullshit.

I'll bet that they're just repackaging a viscoelastic sheet in sticker form... They sell tons of this stuff for quieting down vibration in vehicles, air ducts, motors, etc... It's also really cheap.

ie:
store.secondskinaudio.com/damplifier-pro-20-sq-feet-trunk-pack-12-sheets-butyl-vibration-sheets-cld
  • 4 3
 @vinay: does anyone else find it suspicious that Vinay has no pinkbike profile, and just so happens to offer a voice of support for this snake oil bs? Sounds like a company representative to me. C'mon, at least TRY to create a believable fake avatar.
  • 1 0
 @vinay: So there is nothing really balancing here. You put a weight on one fork leg, but not the other? You put a weight on the hub but not on the rim? Wouldn't it make MUCH more sense to actually remove weight from the offender instead of adding weight to the non-offender?
  • 2 2
 @erikkellison: what? He's here since years, one of the most polite and sense making dudes. Paranoid much? Wink
  • 3 0
 @sevensixtwo: Your comment caught me way off guard and brought me to tears laughing
  • 5 7
 @erikkellison: Sorry, I'm not going to bother creating a full profile everywhere. Then again, Vinay is my real name so maybe that balances things out for you.

@Thustlewhumber: There are different ways to dampen out vibrations or avoid resonance and for each of these approaches there are different ways too. One approach is to balance out a wheel using weights. This is most common and makes a lot of sense to do. It is well worth the weight you're going to add but as I mentioned previously it may be near impossible to do if you've got liquid sealant in there. I think another WC DH racer added weight to his frame, wasn't it Jack Moir? And I read somewhere (ex 4X racer and current EWS racer) Jared Graves likes a bit more weight here and there too, though I'm not sure whether that's actually balanced weight. But as for the AXS technology, it isn't claimed to work by adding mass here and there. In fact they may actually try to avoid it, which is why they stick it close to the axle (onto the hub shell).

One other way is to change the stiffness. And that isn't just the E-modulus. It is about the structural stiffness actually. So the amount of material, the shape of the cross section or other reinforcements matter too. This includes tensioning, like we do with wheel spokes, guitar strings etc.

Now what this AXS technology claims to do (I just read the article, haven't done any further research) is to change the stiffness of the base material (magnesium fork lowers, in this case) by means of electricity. And the electricity is generated due to electrochemical reactions between the base material and their sticker. Now this is where I am out of my depth. Yes I do know you can do this with certain ceramics. Your speakers (or maybe just the tweeter) work this way. I wouldn't be surprised if this could work to some extend on metals too. I can't give you a resounding yes there (and nowhere did I do so), but I wouldn't say no either. If it works as they say it does, I would be concerned about corrosion though. Not sure how quick it will go, but the aluminium or magnesium it sticks to is going to corrode. Steel and titanium may be better off but that could very well be the reason that it won't be effective there either.
  • 5 1
 TOTAL horseshit
  • 2 0
 @WAKIdesigns: They say the same about steel don't they. And titanium too? Is it only Ali that apparently is really harsh and unforgiving and prone to vibrations now?! : p
  • 4 4
 @Andy-ap: yea, I have an aluminium hardtail. I'm stuck in a limbo for not being cool enough by not riding steel and not fast enough by not using carbon. I had this Cro-Mo HT in the spring, and I swear it had this "feel" to it, like having an inch or two of travel but still keeping it real by having an HT. Such a noble feeling it was, that I thought I wasn't worht it, hence I had to change to what I deserve, and that is harsh reality of aluminium that has no (Cotic) soul. It doesn't rust though, has 30.9 seat tube, tapered steerer, weighs a kilo less, costs 120£, has 135 QR, accepts 26" wheels, gets 100mm fork and all the nonsense. a conneseur or racer wouldn't even fart to appreciate. OOOOH and it doesn't have a hand crafted batch on the headtube... terrible, terrible...
  • 8 1
 @vinay: It definitely doesn't work with any materials people make bikes from - it's one of the most important first lessons in engineering - a material's stiffness can't be changed, because it depends on the strength of the atomic bonds within the material. Atoms bond in very specific ways, depending on their structure and the structure of the atoms they're bonded with, so the only way to change a material's stiffness would be too physically alter it's atomic structure, which effectively means making it a new material.

As you note, if there's actual current flow between the patch and metal (which the paint may prevent), then all you'd get is corrosion.

The other massive problem is that frames are made from a massive variety of aluminium, titanium and steel alloys, in an even wider variety of tube profiles, connected through different bearing and linkage layouts. That means they're all going to experience different frequencies and modes of vibration during the same conditions. These patches would have to be custom for each bike, both in design and placement, to target the specific freq and mode characteristics of each frame, but they aren't.

Essentially, there is no single credible piece of justification in their provided explanation for why these patches should work.
  • 2 1
 @Smevan: Totally, Young's Modulus ("elasticty") of a material is constant. You can do thermal treatment, hardening or alloying it won't change. So I doubt a lot that some small capacitors and inductors can do that. Changing the modulus with electromagnetic fields is pure lab stuff, there is some research about it. Can"t be done within a 5cm² sticker, sorry this isn't year 2100 yet.
  • 1 0
 @Smevan: Thank you for applying some engineering logic. Although I'm sure nobody here is falling for this bs anyway. I might add that theyre being stuck over paint so any electromagnetic interactions would actually be occuring outside the basematerial. Also fork lowers are magnesium, there is no way a single patch material could possibly create the same atomic interaction with both Al alloys and Mg alloys. The rider here has even stuck one to a carbon fibre frame member. Seriously rubbish like this should be illegal to sell
  • 5 1
 A quick follow up: on their website, they give another explanation:

"Reducing the amplitude of each vibration through the interaction at the very heart of the material by diffraction effect, our product..."

axxios-tech.com/bike

Diffraction isn't even an electrical effect, in the sense of potentials and currents, etc - it's the divergence of electromagnetic waves during wavelength-scale interactions, such as passing through a thin slit. Funnily enough, the same 18th Century scientist, Thomas Young, is credited as pioneering both the Young's (elasticity) Modulus of materials *and* performing the first electromagnetic wave diffraction experiment, to prove the wave-properties of light, so it's almost like someone at AX/ Axxios has just thrown those two, unrelated concepts together after reading his page on Wikipedia, in the hope no-one would fact-check them.
  • 5 4
 @Smevan: lots of DH pros tape their sore muscles, and it's been well proven for muscle taping to be a bullsht. There's enough doubt in benefits of compression clothing. Yet all these guys do it. I am quite sure "Faith" helps Gwin being more self confident and more focused. The first race I attended was XC Marathon, all the guys in the team I stayed with spent 30+ minutes putting "warming cream" on their bodies. I asked with laughing voice - what are you doing, it smells like crap. And they all gave me a look: you noob, it warms up your muscles. So I believed it for 5 years or more... So I'm all fine with all that superstition, as long as someone doesn't give me that look: "So you don't know? Listen boy what it does is (...) "

I am more than glad that those bracelets spawned such reasonable discussion, makes me think that Humanity actually is developing Big Grin
  • 2 1
 @WAKIdesigns: I've been on steel hardtails for well over a decade now. I've had an aluminium hardtail before that but it's been so long that it's difficult to compare. I do recall that when I first made the switch (to a steel Voodoo Erzulie) I loved it instantly. I think the flex helps with traction in corners and my friends mentioned the could see the frame flex when I landed sideways. Which I think they must be right about, because I could hear the tyre rub too. But I'm not one who could quantify how much flex there is. When it happens, I'm too busy looking where to go Wink . That said, of course any material can be used to flex an equal amount. The thing is, you can't keep bending aluminium for too long as it will eventually break due to fatigue. So they use oversized tubes to limit the deformation. This is less of an issue with steel and titanium so they can use thinner tubes, still make it strong enough but it will flex more than aluminium would. If you want high stiffness over low weight, it is hard to beat aluminium or magnesium. Simply because structural stiffness largely comes from "height" (or tube diameters in this context) and because of the low density, aluminium can give you this height without too much added weight. That said, frame builders nowadays use 6000 or 7000 series aluminium for their frames because it is very strong. This is what people look at. But these don't have the best fatigue properties. A friend had 2000 series frame from Myata, a Japanese brand. This material may not be that strong but it has much better fatigue properties which meant they could use use smaller diameter tubes hence make it more flexy. He loved it (not sure whether he still has it). But you can't sell that now. If you use 7000 series, you brag about it. If you use 6000 series, you come up with a special name. But you never, never ever make a frame out of 2000 series aluminium.

It isn't all about stiffness though. Damping matters too. I heard that it is more the resonance which makes a frame feel uncomfortable than the actual knock. You hear it when you tick it. Wood sounds dull no matter how much wood you use. So a wooden frame would dampen a lot of vibrations hence would probably feel comfortable. Aluminium is really resonant, steel and titanium are slightly below that but apparently enough to make it noticeable. As for carbon, I don't know. I'm tempted to say it would be more in the resin used than in the carbon fibres themselves.

@Smevan: I do know the Youngs modulus can't be changed through metallurgy. I also know that piezoelectric materials can stiffen under an electric charge. What we have here is not metallurgy, they're not changing the alloy. Agreed metals like magnesium (fork lowers) or aluminium (hub shell) aren't piezoelectric ceramics either. They are reactive though, it shouldn't be too hard to get a current running if you damage the coat and attach a metal sticker to it. What is being explained in the article is something that resembles a piezoelectric process which, as I mentioned, is a subject I'm not comfortable enough with to either completely slay or believe. It takes a more thorough article by the company itself for me to develop a stronger stance. And based on that, a bit of background research too. As it is now, they stick these to pro bikes only so it is not something I should worry about at this stage. Most of all, remember that this short explanation isn't first hand. Even a quote could be out of context. I've read quite some stuff where it became quite apparent that the journalist completely slaughtered the well intended explanation of the company representative. I know a professor who, because of that, refuses to give an interview. Because they write nonsense and put his name underneath. But yeah as it is now, the article hasn't convinced me that it does actually work yet none of you has convinced me either that it doesn't. Seems like a few people have a hard time accepting that.

As for diffraction (sorry, still haven't checked their website, just your response) it seems they're referring to the physical vibrations. You can do that. It is like playing an open string on a guitar and then gently touching the string just above the 12th fret or near the 5th or 7th. They call these harmonics in music, or frageolette. But it is a form of diffraction, isn't it?

I suppose if they ever plan to offer such tuning service to the general public, they'll publish their own explanation. Most likely though, they won't. The general public is not likely to accept accelerated corrosion in their fork lowers or hub shell as well as the sponsored athletes are.

Anyway, I'm reading stuff here in PB that hurts more in a bicycle related context. People need to have their saddle high to apply more power on the pedals? Really, which athlete can apply more power seated than standing up? And we need a steep seat tube angle for technical climbing? I've never seen anyone ride up a really technical climb while seated. I guess low gearing, high saddle with a steep seat angle is great for grinding up long steep fireroads. But calling it like that is never going to sell. But as long as that stuff is being published, I guess AX is free to sticker up pro bikes, aren't they?
  • 7 2
 @vinay:

"none of you has convinced me either that it doesn't. "

fact is, you shouldn't listen to some random dude on the internet. you should listen to what science says. and what science says (you can verify it with any Electromagnetism Textbook, or Optics) is that AX claims are just a big flaming pile of pseudoscientific horsecrap. It's a trick as old as the world. you cover your snake oil with some nice words that resemble those written in a proper scientific pubblication (go to any antivaxxer or chemtrail site, you'll find the same stuff) but taken out of context, mixed up and intepreted in the wrong way. as a scientist, i'm everyday frustrated by this kind of stuff, especially when i realize how many people fall for these kind of scams
  • 3 2
 @Bruccio: Nah, there isn't necessarily something that I should. As I mentioned in my first post here, I just said that this is stuff I only know part of and it takes quite some study to be certain that it simply doesn't work. Maybe some of you are there, I am not. I know mechanics, materials and a tiny bit of adaptive materials stuff, but that's it. I tried knitting for three months, didn't work out either. What I have said is that some elements of the story can work (yes you can generate a current connecting dissimilar metals and it doesn't matter whether you use aluminium or magnesium, but corrosion is going to be an issue) and some arguments against it are untrue or unrelated (it isn't about adding mass to a hub when the rim would have been more effective). I just can't connect all the dots at this stage. Yes I could work my way through all that material and then give you a definite judgement but really, unless I'm in the position to either invest in their tuning service or I'm responsible for talking someone else out of it, I won't bother.
  • 4 6
 @vinay: just nitpicking this thing out: if you can UTILIZE such a microscopic difference in grip between steel and aluminium hardtail, you are wasting your time on the internet. You should be competing in BMX Olympics Smile Yes Steel IS better at damping vibrations, and what are you going to do about it?
  • 2 2
 @WAKIdesigns: Nitpicking the other way around Wink , I wasn't happy with the geometry of the aluminium hardtail, I liked the looks of the Voodoo so that's what I got. And I liked how it felt. Maybe it wasn't just the amount of grip I got but it was more predictable. There is a range where you can feel that it is about to wash out (on dry hard terrain). The aluminium frame stays straight for longer and then it suddenly goes. Can I utilize it? Yeah I like to session stuff. Pick a corner, take it easy the first time and hit it harder every next time. Then again I think I'm one of the rare few who has an aluminium full suspension bike and really finds it much harder to be precise with it. The suspension changes my angles when I go through turns in a way I find hard to aniticipate. It is easier to straightline that bike through the rubble of course, but I just love corners.

Quickly checked the Axxios website (thanks @Smevan), couldn't make much out of it. It doesn't necessarily seem to revolve around piezoelectricity and I couldn't see how they wanted to increase stiffness. It seems like they want to excite the atoms in some kind of anti-frequency to counter the vibrations induced by the trail. See, I could have studied all I wanted about electricity and I still couldn't have bust this. I guess PB and Axxios just need to have a chat then, explain the matter so that we can sleep at night again. Maybe they even have an application that helps against snoring.
  • 5 2
 @Dhminipinner: Didn't refresh the page before posting that follow-up, so I missed your comment, but I totally agree. The crazy thing (and @WAKIdesigns you're touching on this already) is that there are obviously no guys with engineering experience close enough to the teams to tell them this stuff is lunacy, which is surprising :s

@vinay Piezoelectric materials don't stiffen (change their modulus) under voltages, they *deflect*, which is not the same thing - they elastically expand and contract. There's also no instruction on the AX website, or evidence in this article to suggest that the finish is being stripped first, to allow direct patch contact and even if it was, the aforementioned corrosion would then be a problem.

What you're describing with guitar strings is not diffraction at all, but a phenomenon known as "standing waves". What you're doing with a natural harmonic in guitar is touching the vibrating string to introduce a "node" (a point of zero displacement) and force the string into a higher mode of vibration. Incidentally, it's funny you mention the lack of resonance in wood and guitars, in the same post. Wood is not inherently dead to vibration at all and an important thing to understand is that damping affects specific ranges of vibration frequency, so components/systems will always respond to some vibration freqs with resonance. Vibration freqs and modes are also heavily affected by the way the material is used, so you need to look at the component geometry, as much as its material, to assess how it will resonate.

If nothing here is convincing you that these patches are rubbish, then I'm sorry to be blunt, but it's because, as you've shown, you don't understand the relevant physics. You wouldn't stand a chance of understanding Axxios' explanations anyway though, because they're completely nonsensical:

"Several effects also arise as a result of the displacements (compression – expansion) of the vibrations in the material and the induced magnetic field:

the resulting eddy currents are responsible for the occurrence of mechanical forces (Laplace), which counteract the vibratory flow"

axxios-tech.com/systeme-axs

"Vibratory flow" is pure pseudoscience - vibrations don't "flow" and you don't counteract vibrations with eddy currents, since eddy currents do not produce vibration and are not a consequence of mechanical vibration either. Vibration of a non-magnetic alloy cannot induce the alternating magnetic field Axxios claim is producing eddy currents either, so that pat of their explanation is ridiculous too.
  • 1 3
 @allballz: aaaaaaaand he lost it. He started running back and forth screaming, in the room filled with a few people enjoying themselves discussing some sht like anyone else does, he finally hit the wall with his forehead and there he lies.
  • 2 1
 @Smevan: Agreed I'm wrong with diffraction, relating it to guitar strings. Can there be diffraction of mechanical waves? I can imagine of you have set of strings like a harp and you play a chord on another instrument, the strings with the appropriate lengths that go with the individual tones in the chord will resonate. How this works on an atomic level as claimed by Axxios I truly don't know. As for wood though, I'm not saying it doesn't resonate but it does have more damping than steel or titanium, which in turn have more damping than aluminium. Damping changes the natural frequency.

Indeed should have kept the E-modulus out of it too. Piezoelectricity can be used for damping purposes though though reading through their material, I don't think this is what they're doing (see my previous post).

As for convincing me whether it is going to work or not, that simply doesn't work this way. It takes a clear explanation from Axxios about how it is supposed to work. Until then I stick with what I said in my first post: it might work, maybe it doesn't.
  • 2 2
 @allballz: Im mad as hell and I am not going to take it anymore!
  • 3 1
 Legit just showed my physics teacher who has been in the industry for 40 years and he said (In a heavy Yorkshire accent) "What is this shit eh?, I've never heard so much pointless jargon in my life"
  • 2 1
 @vinay: " Can there be diffraction of mechanical waves? "

yes. diffraction (and refraction) are wave phenomena, independent from the nature of waves. their manifestation can be different but the mechanics behind are the same.

"As for convincing me whether it is going to work or not, that simply doesn't work this way. It takes a clear explanation from Axxios"

well Axios can say whatever it wants, but no words are enouh to go against the laws of physics, my friend.
  • 2 4
 @LucasGauci: I would love to see it. "Hello Sir, I would like to show you a discussion online and I wonder what you think about it" - if he didn't tell you to leave him alone, try changing the course to get another teacher. He's an idiot. If he actually read it, he did it out of courtesy and given the involvement necessary to get into it, he probably wants to get into your pants. You may use it as a warning or encouragement...
  • 1 0
 @vinay: "you have set of strings like a harp and you play a chord on another instrument, the strings with the appropriate lengths that go with the individual tones in the chord will resonate"
>That's still not diffraction. Diffraction is interference of waves due to obstacles. I don't think diffraction could be used to dampen vibrations.
  • 1 1
 @Whipperman: Allright then, then I don't see how they're going to achieve that in a material. Time to call in an Axxios tech/representative for a 1hr ask-me-anything session to explain how this thing is ever going to work.
  • 3 1
 Interesting they are listed in a tech article... next up, which color, scientifically, is fastest for xc?
  • 1 1
 @Jimmy0: excuse me, sorry. I have exactly the same question
  • 3 1
 Gwyneth Paltrow has already shoved a bunch of them where the sun don't shine.
  • 1 2
 @DrPete: did you just go South Park on Gwyneth Paltrow?
  • 55 2
 This AX sensor scam are no fresh news. They have been around gor years.
They tried it in DH first, giving them for free to some big names. They tried it a little before ditching it. But then the free add was done for AX.
I don t understand why pinkbike is giving them this sort of exposure. AX must have given good €, and if not not, it s just stupidity !
  • 48 1
 This is absolute bullshit. Pinkbike please stop writing about this.
  • 7 1
 I prefer this name-and-shame-them-until-no-pro's-are-willing-to-consider-running-them approach
  • 5 0
 Either way, PB please start calling them out on this bullshit.
  • 2 1
 Honest to god, it's a gigantic crock of shit. It's right up there with audiophile levels of bullshit (and I say that as someone who's SO hates their audio equipment collection even more than my bike collection)
  • 54 0
 Empirical data or GTFO
  • 4 0
 Agreed - the gains they are claiming are NOT small, and should be easy to verify.
  • 1 0
 Theoretical base for why should it work would be a good start
  • 38 7
 Pinkbike, please make a review on that AXS Sensors. Pretty please Smile
  • 4 7
 Yes I want to see if it actually works
  • 25 1
 And it has to be a blind test. Two similar bikes, one equipped with the stickers in a place that's not easily seen (inside the BB shell, under the fork arch, etc.), so the rider doing the test randomly takes a bike, makes a lap, takes the other one and also makes a lap, then tells you which bike was equipped with the stickers.
  • 9 1
 @Primoz: Or, alternatively, make a specific claim about what the sensors do and test that; For example if its supposed to change the resonant frequency of the material, you can easily construct a scientific test to check that.
  • 11 0
 Also, insist that AXS Sensor provide the science behind their claims of 26% reduction.........I want to see the math behind their claims.
  • 3 1
 @rivercitycycles: To Hell with AXS providing data, hand over a few of sets to Pinkbike and let them test on a vibration meter with a couple of different frames (hardtail, XC, DH etc). If nothing else I would admire their balls if they allowed it, plus I'd fall off my chair if they worked.
  • 3 1
 @Primoz: Absolutely, a blind test is the only way to make it work. However, I think that it should be two of the exact same bikes, with another control. Weigh them each within a gram of the control bike, and use a rider that is perfectly consistent. Next, test this for 4 months on the same trail across 100 riders to gain a statistically significant level of data.
  • 5 1
 @unclemuscles: That's over complicating things. You take the control frame, run it through a preset program on a Vibration meter. Then fit the 'dampers' to the frame, run the same frame through the same program again and look at the results. If the dampers are making any difference at all it will be immediatetely apparent and measurable. The trouble with getting riders involved is that the placebo (or indeed nocebo) effect will skew the result.
  • 2 1
 @Fix-the-Spade: you would have 3 groups. 1 set with a real sticker , 1 set with a fake sticker, 1 set with no sticker
  • 2 2
 Not just no, but hell no. These guys are scammers, and they deserve no such consideration. Their claims are so obviously BS that they deserve only condemnation and disdain. They have demonstrated themselves willing to lie in their marketing (as in a about year ago when they stole a chart from an unrelated scientific paper and claimed it represented science from their sensor). No valuable human effort should be wasted on test of this crap.
  • 1 2
 @unclemuscles: Better yet, randomly put on and take off the sticker off the same bike, no two (carbon) bikes will be laid up completely the same Smile
  • 1 2
 @Fix-the-Spade: That's true, but a rider riding it is much cheaper. And the point here is to make it in such a way, so the rider will not know if there are stickers present or not. And he will have to say if it's better or not.
  • 1 2
 @SJP: this is, honestly, the best option.
  • 30 2
 Is it April 1st?
  • 17 2
 So it is claimed the Ax sensors reduce vibration by 26%. Does this figure come from testing on 26" wheel? So what would happen olif testing on a 27.5 or 29? Well duh! It would be a reduction of 27.5% and 29%. So that settles it. So bigger is better. Lol. Prove me wrong!!!!!
  • 22 3
 That Pivot still looks shit as.
  • 3 1
 Bwahahahahaaaa!!!! Was thinking that too.
  • 10 2
 You mean the fancie bracelets they sold at big five are now available for your bike?? Curious how mechanics and companies will integrate these, especially with a 'flex' pivot.
  • 2 2
 The balance bracelets? I was being sold on one of those while being piss drunk. I still saw through the demonstration (standing on one leg, arms out, the guy pulls on your arm, to the side with no bracelet, tipping you over, and downwards, when you have the bracelet, which is much easier to balance with).
  • 8 1
 How can those little AX sensors reduce vibration by 26 percent? There isn't even a battery! I don't believe this can help when there is so much movement and different terrain that a bike is encountering. How many do you have to even use to see an improvement? Imagine sticking something like a hundred of these all over a car lol
  • 1 2
 +1

AX anti-vibration pad, what, like -- a piece of lead or tungsten weight with double sided adhesive?

Perhaps yes if something is balanced, you would negate some vibration due to imbalance, but this is probably some huge End of the Rainbow BS!

Link please, lol.
  • 21 1
 According to my calculations, sticking upwards of a hundred of them to your vehicle, dependent on mass, would decrease electromagnetic flux and atomic movement quotient by 94%. This would in turn boost overall performance by a quantity of 559% saving so much time (as much as 70 seconds over every minute) that it would effectively send you back in time into the very fabric of the universe... I recommend not using as many as a hundred.
  • 2 2
 From what I can see they may work by having a similar filament layout to a strain gauge, that when distorted by vibration is designed to cause low level electrical currents which are then fed into resistors to essentially help dissipate some of the kinetic energy from the bike's vibration and turn it into electrical energy/heat in localised areas.

If this is how they work, then the theory is at least sound for their principle of mechanics - just how effective they would really be depends on the surface finish, bond adhesive quality and numerous other factors; results would be largely self gratifying in that they would probably end up dampening much smaller, higher frequency vibrations running along the frames finish surface [paint] and sensor adhesive rather than mitigating actual core vibrations running through the component and frame - this would leave the measurable results extremely subject to bias of the manufacturer and almost impossible to quantify a true effect.

...... or I could be talking total BS
  • 3 3
 @ctd07 - that is easy to check. Mount the bike to a jig, put it on vibrating table, measure the temperature of the magic artifact before and after the experiment. Attach a piece metal in same place, measure before and after.

The issue is that Saying that even mr Fluckinger can win a second on a lap is just ridiculous, as I strongly doubt that even Nino is able to deliver such consistency to come within 1 second repetitevely on 20-30min lap. Even on fkng road bike on flat course.

In general bike industry is excellent at exploiting the fact that in MTB variables are many, with human factor being dominant and saying this shaves a second or three and when it doesn't, they will tell you: but track was wet and ruts got deeper.
  • 9 1
 I spotted two sand-corns between the fork seal and the stanchion in the 3rd last pic. How on earth can this be tolerated in a XC-pit??
  • 8 2
 If the tape sensor realy works by absorbing vibrations (read dissipating energy), than it would get really hot. Energy has to go some where and it will be heat (thank you, oh you beautifull thermodynamic laws). Simple experiment for who ever is dumb enough to use them : record temperature with a device (thermocuple, cheap monochrome infra red sensor or so on). Both on the tape and the frame beside it. Go ride. Repeat, feel dumb, drink beers to forget.
  • 3 4
 It could be cooled by the surrounding air fast enough for the temperature to not raise that much. But, saying it could there is like saying it could work in general.
  • 1 1
 @GabrielDugas: Thank you for saving me the trouble of writing exactly that!
  • 2 2
 Okay, why am i downvoted over there?? o.O
  • 2 1
 @Primoz: Because 26% of a bike's vibration energy will definitely get a little piece of foil like that hot if it's all being absorbed by it. DVO put cooling fins on their shocks for a reason.
  • 2 0
 @thealmightybryn: Notice the second sentence, it could be cooled that fast just as it could work at all Wink

Cooling fons on a shock most likely help slightly, but are probably there mainly for the looks. The only dry (yet still dirty) parts on a bike when riding in the rain are the brake calipers, the rotor and the surrounding areas (frame and hub) and rear shock (the effect is not as noticeable on the fork due to higher oil content and higher system mass and no leverage ratio, thereby greatly reducing the damping energy density).
  • 3 1
 Atomic diffusion is atoms transfering from one metal to another. Then they talk about electro mechanical transfer of energy. Would love to see some data proving the reduction in frame stress causes by frequency oscillation reduction.
  • 2 0
 if the entire circuit begins to use them the it will be the next fastest move to abandon them to decrease weight

-I recall many years ago Nico Vouilozz upset about his frame decal weight , so why would an XC bike want deadening material? Less vibration ? Isnt that why we buy carbon frames?
  • 1 0
 I have used something very similar to that silver dampening tape to reduce vibration in a tennis racket! Depending where it's placed on the racket frame, it can change the balance slightly to have a better feeling swing. Neat stuff.
  • 1 0
 Here is a real world report about vibration - flat tire crashed an airplane.
skip to the analysis...
www.tsb.gc.ca/eng/rapports-reports/aviation/2014/a14w0177/a14w0177.asp

An unexpected high rotational imbalance was created on the number 3 tire when it failed during takeoff. During landing, the failed number 3 tire was spun by contact with the ground and was maintained at a rotational speed that was the same as or very close to one of the natural frequencies of the main landing gear (MLG). This caused the lock links to trigger (through the proximity sensors gap) the proximity sensor electronic unit (PSEU) to de-energize the solenoid sequence valve (SSV), thereby relieving system pressure from the extend port of the unlock actuator. In this condition, the excessive vibration then caused the lock links to overcome the force from the downlock springs and unlock the stabilizer brace as a result of gear dynamics, which led to collapse of the right MLG.
  • 4 1
 Awfully muted coverage if that's really Fox Live Valve. Based on RC's first-ride review from a few years ago, I'd imagine it would be a bigger deal here. Right?
  • 1 0
 Call me skeptical on the AXS chips but they have been using frequency circuits on skis for years. Most notably my Head super shape iMagnums. They provide a very smooth ride at speed for their short 163 CM length. By comparison my K2 Richtors use dual cores that move independently to absorb vibration to achieve the same result.
  • 1 0
 Did Fox buy the technology from Rock Shox/Lapierre? I really liked that setup, just wished it was retrofittable to more gravity-oriented shocks. This seems to be nothing new, just not has the Fox Propaganda Machine behind it. If Fox can make it work for my riding though (not XC), I'm all for it.
  • 1 1
 I guess if carbon doesnt work for you at the top level....why not just wrap the whole dam bike and yourself in silly sticker technology?
...or, if all that fails to make you vibration free....you can still rock your spandex on the road circut.
  • 2 1
 I love these cross country tech write ups. It's amazing the tricks they use to save weight and there's always something different and interesting.
  • 1 1
 Bruni and Peaty wouldn't be the first professional racers to talk up a product for their sponsors. Wether it works or not. That goes back as long as there has been, um, sponsors.
  • 2 0
 Reminds me of the old K2 Electro board with piezo. Vibration energy converted to flashing light.
  • 1 0
 I remember that board stealth bomber tech they said
  • 1 0
 @StaticFish: Saw one once. The flashy light made it look so cheap.
  • 2 0
 Dude! If you are willing to put a dropper post on your bike - - go all the way and forget about the short travel model
  • 3 1
 Looks like Fox iRD not Live Valve to me.
  • 1 1
 @mikelevy pretty sure it's just it's bro
  • 1 0
 You're correct - the article has been updated.
  • 2 0
 Shut Up And Take My Money!
  • 7 8
 "At first, I was a bit skeptical with the short stem and tried a longer stem, but I settled on the 60mm one"
- cue the collective laugh of pinkbikers with 30mm flatland bmx stems on their endurobroooo bikes.
  • 1 0
 It's an xc article broooo.
  • 3 1
 Expanding foam in handlebars- this really does work.
  • 4 1
 Spank does that already.
  • 2 1
 If this AXS thing is legit, why isn't it on every touring bike and wheelchair? Cheating at soap box derby etc.
  • 2 1
 If you put two AX sensors together and stuck them on your nose like a Breath Right strip, would it not make you faster?
  • 2 0
 i found the best place to put the AX sensor is up my a%@.
  • 3 0
 WTF sensor?
  • 2 0
 witchcraft. Don't get into XC, I tell you.
  • 2 0
 Wonder how it works on stains?
  • 1 0
 maybe i should pedal more
  • 3 2
 XC top line starters with droppers.
  • 3 3
 How come you don't see gluten for sale if they remove it,where does it go? I need more gluten
  • 1 0
 Here, have some bread with your pasta...
  • 2 0
 You actually can buy big bags of gluten. It's a bonding agent used in baking.
  • 1 2
 Invests in bullshit sticker technology, but not ovular chain ring technology. I want to see one of these f*cking races, do they wear garbage bags over their heads as well?
  • 1 1
 I will wait until they make a frame from it
  • 1 1
 AXS are they using scalar energy idea?
  • 3 3
 if it makes you think your faster you are...
Wink
  • 2 2
 Gullible.
  • 1 2
 Are these the reason why his bike didn't break in that massive crash? Reduces the vibrations by 26%?
  • 2 2
 how the hell does that little sensor thing work?
  • 5 0
 It doesn't.
  • 1 2
 I guess I need to put silver stickers all over me and my bike before the next group ride.
  • 1 1
 Body Vibes for your bike.
  • 1 1
 I see someone has been busy giving negative props!
  • 1 2
 definitely not as good as flash stickers
  • 1 2
 They say stickers makes your bike go faster too
  • 1 1
 retracted
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