Is This Linkage Fork the Future of Suspension? - Crankworx Whistler 2017
Linkage suspension forks aren't a new concept, with the idea being trailed in all sorts of two-wheeled sports throughout the past. Fans of motorcycle road racing still talk about the legendary ELF Honda NSR500 and its wild chassis and linkage front-end that was raced in the 1980s, and mountain biking has also seen a handful of different linkage forks over the decades, from AMP to Whyte and a few others. None of those designs ever caught on, however, and traditional bushing-based suspension forks are obviously still the norm... but should they be?
Structure Cycleworks wants to change that with the 150mm-travel SCW-1 and their linkage fork that's integrated into the bike's carbon fiber chassis. The company knows that they're going to have an uphill battle and that the bike's polarizing looks will be an instant turn-off for many riders, but Structure Cycleworks' Loni Hull says that they're aiming to win people over with its performance, not its appearance.
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The blue bike in the Structure Cycleworks booth is a rapid prototype model that hints at what their production version might look like.
What are the claimed performance advantages over a telescoping fork? We've come to accept that telescopic forks have a large amount of inherent friction, even if they feel smooth, and linkage designs have been proven to be nearly friction-free thanks to the sealed bearings that they pivot on. Less plain to see, though, is the ability to tune both the axle path and the amount of anti-dive, which means that the bike could be designed to handle much more consistently. That should add up to more control, confidence, and speed - at least in theory.
But even if those claims all ring true, the trick might be to convince the everyday rider that this wild looking machine is worth considering. As much as some of us get excited about gear that has the potential to be better, we're a weird bunch that rarely embrace disruptive ideas from way out in left field.
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My test bike was built three years ago as a proof of concept.
The Structure Cycleworks bike and linkage fork are from well outside the stadium compared to what we're used to; not just left field. Part of the issue for what will surely be a lack of universal acceptance is that it's not like the latest suspension from RockShox, Fox, et all performs poorly, is it? No, of course not, but Structure Cycleworks' Loni Hull believes that it's going to take a paradigm shift in order for suspension performance to take another substantial leap forward.
''There's only so much we can do to make forks maybe only a little bit better for next year, but it's all incremental improvement from maximum effort,'' Hull told me when I posed the simple question of why. ''We're designing with a clean sheet; we're looking at how to make a bike ride better for a rider. It performs well enough that I feel there will be a market for it with people who want something that's a quantum leap over the best of what's currently available in enduro,'' Hull went on to say, clearly not short of confidence in the design.
 | We know that it looks weird. We tried our best to make it ascetically pleasing given that form has to follow function, and function comes first for us. All we care about is making the bike work the way we designed it to work and to give some advantages that telescoping forks can't offer. |
Loni Hull poses with the rapid prototype model.
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The linkage design activates a RockShox damper to deliver 115mm of travel. The production version will have 150mm, however.
Hull explained that the most notable advantage to their linkage system was that the bike's front-center length actually grows longer as the fork goes through its travel, which is the exact opposite of what happens with a traditional suspension fork that shortens the bike's front-end and steepens the head angle when it compresses.
The Structure Cycleworks linkage design actually lengthens and slackens the bike's front-end by as much as a whopping eight-degrees for their 150mm-travel fork, and by about five-degrees for the 115mm-travel fork that I briefly rode. Why would this be a good thing? Getting the front wheel farther out in front of the rider, especially when the fork is deep into its travel, is only going to add stability and keep the rider from feeling like they're about to get chucked over the handlebar.
Even if it performs better than a traditional fork, will mountain bikers be able to get past the appearance?
Right now, a fast and aggressive rider often has to over-pressurize their fork's air-spring if they're facing a steep or rowdy trail, something that compromises small bump action. If the Structure Cycleworks linkage fork performs as claimed, a rider shouldn't have to make this concession. ''We take a rider's center of mass and we look at how the kinematics move around that center of mass,'' Hull explained. ''What we decided is that we didn't want a force-path that brought the axle in a kind of J-hook pattern; we wanted one that maintained the front-center and came up more vertically before it starts to go back into a slacker angle for the big hits.''
That's plenty of talking, but the truth will only come out on the trail, so that's where I went. The futuristic looking blue bike in the Structure Cycleworks booth is actually an unrideable rapid prototype, but they did have their older proof-of-concept machine on hand that they let me take out. This bike is unapologetically rough - it was created three years ago purely to prove that their system has potential. So off I went to find out how much potential it has.
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The prototype bike has 115mm of travel up front but it feels like more. And yes, that is a highly modified Norco rear-end you see.
My three-year-old test bike had some fairly dated geometry and a long-ish stem, but you know what? The damn thing felt like a mountain bike to me, and I mean that in the best way possible. The 115mm-travel linkage fork definitely did not feel like a normal fork, though; it was impossibly active relative to how much travel it has.
I'd go so far as to say that it was more supple than the newest 150mm-travel forks on the market, enough so that I first suspected an under inflated front tire, which wasn't the case. I spend a lot of my time on 120mm-travel suspension forks and none of them are anywhere near as active as this odd looking linkage contraption.
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The fork was impressively supple, far more than a standard short-travel fork.
My other thought was that the bikes front end felt very torsionally rigid. Yes, at well under 160lbs I don't exactly find any fork to be all that noodly, but it was quickly obvious that the Structure Cycleworks front-end doesn't flex as much as a traditional fork that depends on its axle and arch for rigidity. The linkage fork that I rode is over three years old, and it's little RockShox damper sees too much leverage, but the action was still impressive and, most importantly, very controlled feeling.
In fact, if it was somehow possible to do a blind test without me smoking a tree head on, I'd likely get off the bike saying that it's running some sort of high-end, 150mm-travel fork, which is quite the praise considering that it's actually a three-year-old design with an over-leveraged damper and just 115mm of stroke.
In fact, if it was somehow possible to do a blind test without me smoking a tree head on, I'd likely get off the bike saying that it's running some sort of high-end, 150mm-travel fork, which is quite the praise considering that it's actually a three-year-old design with an over-leveraged damper and just 115mm of stroke.
It looks different, but the prototype performs well enough that I'm looking forward to trying the new version.
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What good is a test ride if you don't actually test the bike? Getting airborne on the prototype.
So, is this the future? Yes and no. I believe that a linkage design does offer some substantial performance advantages over what we're all using now, especially in a long-travel setup. And Hull is also likely correct when he says that the paradigm shift of a proper linkage fork is the only way to get more than a few percent performance jump over today's high-end forks. But even if all that does end up ringing true, I just don't see the majority of mountain bikers being all that accepting of the design.
The Structure Cycleworks bike is just too disruptive, too out there to become the norm, and there has been of decades of development and acceptance of traditional suspension forks. Regardless of those facts, I won't be the least bit surprised if and when the 150mm-travel SCW-1 comes out and really does blow current bikes and suspension forks away.
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It's like creating an entire 6 step process to help drink a glass of water, when all I really needed was simply a glass to drink from.
Also, I'm not confident, AT ALL, that this design could survive a huge case or gnarly OTB crash without the bike and rider getting seriously F*'d up.
Gold star for trying, but this duck is dead in the water. I wouldn't waste any more time or money on R&D for this concept. It looks great in the pits for a "PB Randoms" post to help bring attention to your brand but that's about it. Great effort though guys... good luck.
"That's about it" except for the part where the guy who actually rode and tested it said that it performed great and that he wouldn't be surprised if the final versions blow the current crop of forks away. If you want to argue that the bike looks weird and won't catch on that's fine, but you have no clue about anything else.
Congratulations, you're an internet dick. You get a gold star too, right next to this shitty suspension concept. Great job buddy.
If the answer is yes then I will apologize for saying you have no clue. If the answer is no, then I stand my my original comments which are that you don't know shit about this bike. It not a personal attack on you, its just pointing out the obvious.
This new linkage is a radical departure from anything made by almost every player in the market, addressing many of the problems inherent to the telescoping suspension fork. Additionally, Mr. Levy here, who has extensive experience riding almost all new tech on the market, generally gives well balanced reviews. He said the unrefined 3 year old prototype of this design was actually GOOD: better in some ways even than the extensively developed telescoping fork.
Long story short: we have issues with the lefty because it didn't really improve much. This could have the potential to revive the relatively stagnant development of the front end of the bike. HOPE my friend. Hope.
Please don't let them make it, please don't - starts to cry
Dumb and Pretty vs. Intelligent and Ugly. Who cares how it looks, everyone will get used to it after 10 years and think it's normal.
I understand people not wanting things more complicated, but it might be worth it. Just wondering the weight comparison. Seems like this could become a thing for downhill racing, until they invent a nice soft cloud to float down the mountain on or some kind of hover-bike. Hover-Board …
We realize not many people are riding Di2, but we still wanted to provide a clean installation option for it - and for any Fox products will share the same battery.
As @Socket mentioned, this is very different from the VPP. I would describe it as a mildly rising rate, overall, with most of that rise happening in the last half of the travel.
Seriously, we gave this concern a great deal of thought, and we can't imagine a scenario in which our bike is more dangerous than getting hung up in forks legs, bridge, bars, or cables on any bike.
We all enjoy a dangerous sport, and your concern, while important, represents a small part of the overall picture. We propose that our bike, with up to 40% less inclination to dive under braking, more than makes up for any concern about entangled appendages.
Front linkage designs will always be unusual, but they really are the only way to gain full control over front suspension dynamics and we think the ride quality will make it worth getting out of your fashion comfort zone!
We've designed it to stop just short of contacting, but if you manage to compress it hard enough to flex the chassis a few millimeters, there's a bump stop to cushion the blow - though it won't save your body, which might be in a rough state at this level of load!
Make it follow the current long, low slack dynamic and I'll buy one. Telescopic forks have needed to be challenged for 30 years but fashion Nazi's have stopped all attempts. Get it some fully floating brake linkage and we can go full Valentino Ribi!!
Did I just explode my brain? it's possible
We will have three chassis, each with significantly different personalities, and we can customize each to fit almost any rider (within reason, of course). It's more like sizing a snowboard than sizing a bike.
The smallest size, Gravity Level 1 (G1), is agile and playful, with our built-in stability enhancing dynamics. G2 is a progressive enduro length - again, with added "stability on demand" that makes it more stable than a downhill bike at bottom-out. G3 is a monster: at bottom-out, it's on comparable to an Extra Extra Longest Geometron*. To be honest, I may revise it down a little, as a sled of that size isn't for everyone!
* We're huge fans of the work Cesar Rojo, Chris Porter, and other geometry pioneers have done to help the market understand the value of increased length and trail!
Decoster brought the Ribi designs with him to Honda and convinced Honda to purchase the rights. Which they promptly shelved for production cost and weight issues (hard to implement CF on Moto and remain in a price category. You should see what Dave Weagle has developed (look at his patents for Orion)
This is the best attempt I've seen this far to truly offer an alternative fork design. The genius is also the tunability of the dynamics. Pick a shock, coil or air? Ohlins or Fox or RS? Remotes? All pretty much off the shelf and widely available alternatives.
Options are good. I like options. I also like performance advances. This looks like both.
Dammit, you got me. You've won this round, @vespertilianus!
For real though, looks quite interesting, hope it takes off, even if only to shake things up.
"
Also, this goes out to @Structure-Ryan, would I be correct in assuming that despite the lengthening of the front-center the axle path is not actually forward with respect to an impact but rather neutral and it is only the motion of the front wheel with respect to the frame that causes the lengthening of the front-center?
Thanks - glad you like it!
I'm answering questions as quickly as I can while staffing our Crankworx booth, so forgive me if I direct you to my reply a few minutes ago about the axle path. The short version is that Mike's statement was a minor error: our front-centre shortens by a couple millimetres, so it's only lengthening *relative* to what a telescoping fork does.
I think it looks pretty well executed.
Structure Cycleworks: Here you go!
PinkBike Users: um.. insert any comment above> actually... we are happy with the generic spoon-fed updates we are getting fed by the mainstream industry, thanks.
I often have a knee slapped against the top tube and this looks a bit scary for that position - and in a crash - what prevents the moving parts at the front of the bike from pinching errant appendages?
The final version (still being drawn) will have narrower and smoother lower links. We have never scraped a knee on the links, though, as they're more out of the way than they might appear.
For the front, the carbon double crown fork limits steering so it won't pivot to a dangerous point (a little less than a DH fork, though), the front end will be fully extended to a static state before you could spin your "appendages" into that location, and the parts will always be opening as you wrap around it.
The space at the front of the bike is surprisingly well protected by the handlebar and wheel. I don't know about you, but I've never been tangled in the front cable loops of a DH bike, so I think you'll be fine!
Also, see any videos about the GS challenge (where they all race BMW 1200 GSA and you'll see that this suspension design is not only used in their road-going motorcycle. Agreed the GS Adventure is not an hardcore off-road machine but it can still take a beating.
I recommend anybody interested in suspension design (motorcycle or bicycle...) to take a look at a book called Motorcycle handling and chassis design by Tony Foale (you can maybe find a pdf online)
But I agree, I would rather ride this fork on a smooth track with big hits than a rough one.
Our front-centre remains almost constant with a fairly vertical axle path. It only lengthens relative to what a telescoping fork does.
The effect isn't so dramatic as to make it difficult to get over obstacles. In fact, the lack of friction, due to pivoting on bearings, gets the front end moving so easily that you probably won't notice any detriment to the more supportive axle path.
And if you want it to be plusher, there's an eccentric (essentially a flip chip) that can be used to dial in more plushness with less aggressive support.
Also being able to change the leverage curve to math the rear suspension would make a very balanced feel front and back.
The front suspention would be made from carbon fiber.
Weight would not be an issue.
Sloppy pivots?
Are those an issue on any rear suspension?
Looks weird but i think this would work as a trail bike.
And.
The bikes we see today, seem to us nice and rad, because we are used to these visual characteristics!
So,
All I want to say (to those haters) is to step back and think before posting their... hate. Behind all those new ideas are people who Do love our sport and have invested their precious time (and money) developing them. Much more if the final product is so refined as this nice / rad looking bicycle.
Respect, That’s all.
I remember when:
Air Suspension came out. People freaked.
1x systems came out. People Freaked.
Dropper posts People flipped
27.5 Nope
26x24 wtf
Dual Crown Hell no
Taper Head Tubes WTF m8
1.5 Head Tubes COME ON
Carbon Bikes HELL NO PLASTIC
Carbon rims NOPE
Oval Rings WTF is this?
etc etc etc
Some things are dumb, yes. However....
The modern MTB is as dated as the Internal Combustion Engine from an engineering standpoint. There are many better options for performance. But, 'Its not what we're, *I'M* used to!' Thusly, it will be killed off and progress will never be made.
They said man will never go over 60mph too at one point.
Compression = Wheel base Shrink/Head Tube Angle Deflect and front end control lock up.
I'll keep an eye out if you guys go to production.
Keep it up!
As counter-intuitive as it seems, the steering is *more* direct than with a telescoping fork! The carbon steering links (which will be even larger on the production bike) are extremely rigid and move on bearings, rather than the softer bushings of a telescoping fork. This, combined with our short, stout, carbon double-crown fork make for an extremely stiff front end. The production version will be several times as stiff as the one Mike rode, which he noted was still quite direct.
But there's only one way to prove it, so throw a leg over the production one in about a year and see for yourself!
Our experience here at Crankworx has been extraordinarily positive. When we spend a few minutes - often dozens of minutes - discussing it with visitors and showing them the genuine article, the response has been fantastic.
Yep.
Keep up the good work. The fashion minded haters will post all kinds of low IQ commends. That’s already a fact. They do forget that the same happened with the first full suspension frames, the first forks, the first disk brake systems and more. Much more. It is really funny to recall the bike fashion “experts” hitting hard on anything new (I remember so many negative comments about the early suspension forks. So many disliked them just because they had straight legs!!!).
The same stands with the yellow fork forest (there were so many yellow forks back then!!!), the fluo colors, the frame decals, the hydration packs colors, the baggy shorts, the jerseys…. COME ON!
As for the “too many bearings” sceptics, just take a look at Motion France’s fork. Their fork is equipped with synthetic bushings which are service free!
Your design is not only promising, but has the fresh air of innovation, like the designs of the early days of Mountain Biking…
In the end I see it as another choice, not the only choice. I like the outside the box thinking. Best of luck in the development/deployment.
It takes an open mind to look at, but it's surprisingly neutral to ride. Most people who ride it describe it as "disappointingly not weird"! What many find more surprising is how weird a telescoping fork feels after a few hours on a WTF front end.
Give it a try some day and let me know what you think!
I love to geek out over bikes, and if I was a different kind of engineer I might even try my hand at bike design. But skill and (like @ghotinori said) fear are my biggest limitations. The pro's prove daily that most any bike can handle riding far above my abilities. So I wonder - even as I drool over fancy new bikes and clever ideas - what the critical areas of bike improvement really are?
Note that I don't say this to discredit the design, but more in introspective response - which I think a new design/idea should inspire in us.
A few difficulties with past linkage systems relate to 1) integration with the rest of the chassis (many replace a telescoping fork and slot into a standard front triangle's beefy steering head, which I find too limiting for a number of reasons), 2) axle path (most follow a force vector that creates a J-hook axle path and tucks the wheel; not good for stability or rider confidence), and 3) stiction and rapid wear in the system, with riveted bushings, spherical joints and other sub-optimal hardware in the load path.
We feel like we've done due diligence to avoid those things and offer a bike that is super supple and active over small impacts while offering useful resistance to dive and increased stability as travel approaches full bump. We also went the extra mile to make our control arms (as we call them), TT, and double-crown fork beefy and stiff so as to avoid torsional or lateral deflection in the system.
We aren't sure what more we can do other than to keep riding the telescoping fork bikes we already know and love. It wasn't contempt for teles that motivated us; it was love of riding and the hope that there's still a fair bit of room to evolve biking for as many as care to join us.
Mind you, I am not knowledgeable on this, or pretending to be, just curious.
There are also limitations to the use (and abuse) that Duolever could take if directly translated to long-travel bicycle use. Duolever has top and bottom links attached to the cast fork unit by means of ball joints that are in the load path, which we feel would be less than ideal on a bicycle for reasons of stiction, weight, and wear -- none of which is as great a concern on a large touring motorcycle.
Because of what we are doing with axle and load paths on the SCW 1, telelever simply wouldn't allow us to control axle path, rake, and trail in the manner we intend.
I don't even mind that it's ugly! 26'ers are ugly.
Well before I got into Mountain Bikes I was into motorcycles and road racing. I remember bikes like the ELF3 NS500 (not NSR guys!), Bimota Tesi, Yamaha GTS-1000, and various others. In truth, there was a very big need for the consideration behind these designs because the forces dealt with are far greater than what we see on mountain bikes.
On a motorcycle it was recognized that forces generated during breaking and suspension action were transmitted into the frame heading up the fork legs and through the frame head. That's why frame spars, fork legs, and triple clamps on motorcycles GOT HUGE in the 90's. This fought flex in the system that was flawed due to the path forces acting on the system had to take. Forces that caused a lack of steering and tracking precision as well as amplifying stiction.
On bikes like the GTS-1000 and Tesi, this path was optimized and forces traveled straight back instead of going up the fork legs then down the frame spars.
To this point, I could never see another reason for doing this on a mountain bike and after reading this article I still don't!
* A variance of up to 8 degrees in head angle as the susenpsion moves through it's travel? That's insane! At the limit, you don't want to alter things that can upset the current level of traction. Leaned over at the limit, a decreasing head angle put's one in danger of no longer having enough weight on the front to maintain traction!!!!!
* The mountain biking industry needs to experience the same moment motorcycle road racing did in '93 when it was recognized that everything got too stiff!!! In particular, sidewalls got too stiff and frames got too stiff. And so compliance started being reworked back in.
Trying to introduce small bump compliance is misleading. How small of a bump is considered small? And how small must it be before it's something you can say needs to dealt with by introducing compliance? Forks and shocks these days are actually pretty damn good at being sensitive. It's tires that need to be made better. The mountain bike industry needs to realize what motorcycle road racing and Formula 1 already know: that the tire is the first part of the suspension system.
And don't be so sure what the industry believes, knows, or when they get a clue. Gary Nixon complained to Honda for a good bit about how much the front forks were flexing before they showed up at an event and actually watch him bend the forks under braking at the end of a straight.
Never mind that they can't figure out how to make a tire that can remain compliant and not be prone to flatting or coming away from the bead.
They did, it's called UST, and nobody bought it.
This industry is dumb!
That said,
1) The angle "is" going to steepen when you hit a bump. How much so? And considering it's a bump, FOR HOW LONG? If you actually notice that steeper head angle when hitting a bump, you're doing it wrong.
2) If your front fork is diving a lot when you hit the front brakes (there by also causing the head angle to get steeper) USE MORE LOW SPEED COMPRESSION as a form of anti-dive.
Valid concern! If there was a way to make the steering links less conspicuous, we would've done it. Actually, the upper mount will be moved below the upper head tube on the production bike to keep them compact, but that's as much as we can do. Folding rearward would require compromising the frame to make room for them and no one wants a heavier or weaker frame!
Seriously though. It's not that ugly and good performance means a lot more to me than looking cool like a a bro. I wonder how it'd ride with a coil on there.
My wustion then is, how much bump steer does the system see? Granted, you rarely have an issue with this since steering angles at large shunts in the front are minimal. I also suppose te bump steer is small, but it must have been considered somehow?
Yes, the changing alignment between top and bottom *when turning* requires the spherical bearing on our steering link.
Bump steer in two-wheeled vehicles is a tricky variable. We chose to minimize it by aligning the two axes at sag; they go out of alignment through the travel by only a tiny amount and bump steer is virtually nil.
In the future, I plan to make some prototypes that take advantage of bump steer in an attempt to fine-tune the steering feel. There are numerous variables with far greater impact on handling, though, so this effect could get lost amidst the more significant effects.
The gearbox is another "holy grail" product in the mountain bike world and we're as keen as you are to see it succeed!
The final bike will have the upper mount moved below the upper head tube to keep it more compact. We agree it's a prominent feature, but it really is the best way to connect the upper and lower. Much more direct feel than a telescoping system - and more compact, too, at full compression.
They also say the (early, unrefined) prototype never needed new bearings so far.. i cant remember ever having problems with my bearings on my cube, scott or trek rear suspension linkage.. maybe i just dont ride as wild as you do
Difficult as it may be to believe, our design intention is to make a bike that's as predictable as possible. The Horst link allows us to keep the anti-squat, anti-rise, and motion ratio very consistent throughout the travel. Similarly, the front end is intended to reduce the bad habits of telescoping forks. It's a complicated design that's designed to simplify your ride by not forcing you to compensate for quirky dynamics.
Everyone who rides a Structure tells us they were expecting something conspicuously exotic in the ride qualities, but it's frustratingly non-weird!
A very simple argument for this design........
If telescoping forks were the best then why not use on the rear too ?
If the rear 4 bar type rear suspension system is working well....why not use on the front too ?
Why do you think many other suspension systems DONT use a simple telescoping design?..........its because it just has a linear axle path, and in many cases is not going to be able to optimize the damping requirements in the same way as curve linear axle path.
Visualy i like the shock position of the proto better...it is slightly more central. Why not try and have the shock placement lower for better CG ? Was the linkage weight too much ?
You should look into the use of AI genetic algorithms to optimize....
The shock on the Generation 2 (blue) bike is actually lower. The standover is so much lower that it may make the shock appear higher, but any lower and it would contact the tire!
but following this.. mentality, we should turn away from anything new. No matter how promising seems, no matter if the current technology (...meaning "forks"), passed through a period of wild experimentation (and problems)... (ok. for knowing that you have to be ridding bikes -on dirt- for more than 25 years)
so,
shall we ban all experimentation for the fashion nazis?
Be strong, you’re going to hear a lot from ignorant people. I know, I’ve been there…
What bottoms out first? The shock(front) or the fork/steered tube onto the top steerer tube?
The shock bottoms out just as the rubber bump stop begins to contact the lower headset. The bump stop engages only if you manage to flex the chassis those last few millimeters, which would probably be in a crash situation.
To answer more seriously, though, the control arms would probably get a bit longer and have to be beefed up, but that's not surprising. Stack will get pretty high due to all that travel plus two headsets, but nothing that can't be solved by a flat bar and, if necessary, a drop stem. Not insurmountable - and the greater the travel, the more our system shines.
I'd love to do it, so who knows!
Until then, we have a YouTube page under Structure Cycleworks with a short clip posted of riding down a pretty sketchy stretch of very round 4-6" river rock. Although we've since ridden and jumped very aggressively (and so did Mike Levy, it seems), we've focused on riding and engineering instead of keeping a videographer around...definitely to a fault.
Once we get the fork crown on the prototype fixed, we'll focus on getting hard rides on video (the crown became loose relative to the steerer after "smoking a tree head on" [see article]. No frame or linkage damage, it's important to note).
Forgive my enthusiastic niece in the video :-)
Thanks for the support! It's not for everyone, but we think those with an open mind will be thoroughly impressed!
You're not wrong about the cost. To be honest, there are entry-level full suspension bikes that cost less than what is costs us to make this chassis. Thankfully, the direct sale model allows us to sell it for a price that's not terribly out of line with the current upper tier of carbon enduro bikes. We wish we could offer this at a price that everyone can afford - maybe some day!
There are two ways I like to frame the value proposition:
1. If you look at the difference between a mid-level and upper-level bike, we believe we offer a greater incremental benefit for the extra cost.
2. If our design was the norm and someone proposed saving a couple grand with a telescoping fork, complete with its drawbacks, perhaps we would be seeing an equally polarized comments section!
It's vertical axle path a good thing? I don't think so, but the head angle doesn't change and that sounds good...
I dare not even think about an e-bike version... oh the humanity... those poor keyboards, getting smashed and spat on with all the furious hating...
Unfortunately, reversing the links would require removing material from the rest of the frame, which would compromise strength or weight. The production steering link will be mounted below the upper head tube for even better stiffness and shorter links.
Thanks! Personally, I'm all about the naked carbon, but this blue colour looks so good in the Whistler sun that even my industrial-chic tastes are being won over!
also this system slackens while compresing unlike a current fork? but if both front an rear suss compress at the same rate would'nt head angle remain constant? (unless it's a HT)
Alsi, I would'nt trust that long unsupported top tube on landing a big drop!!
The long unsupported top tube is only carrying the weight on your hands, unlike a conventional fork.
We really, really want to build a downhill version! It's a difficult business case, though, as downhill sales aren't what they once were. Still, the more travel, the more our "stability on demand" design separates itself from telescoping forks, so a longer travel implementation plays to our strengths.
This is something we debate frequently and I won't rule it out ...
(apologies if anyone else has mentioned it up ^ ^ ^ ^ there, I couldn`t see anything)
I am sceptical on the force produce on the rigid fork and on the "space" between fork and bar.
a non comment frame for sure.
Did your fashion sensibilities get offended?
Valid concern about axle path. Ours isn't forward; in the more supportive configuration, it's nearly vertical, while the more compliant setting incorporates more rearward motion.
Our experience is that replacing sliding bushings with bearings provides so much smoothness that it more than compensates for the axle path issue.
Our feeling is the front and rear need to be able to work independently, but if someone can make your idea work, I'll be the first in line to congratulate them!
The way we've addressed this is to make it easy to get weight over the front and allow some transfer under braking. Rather than seeking 100% brake anti-dive, we reduce dive by only 30-40% vs. a telescoping system (depending on position of our frame eccentric). In real-world riding, what this means is that the bike feels stable and brakes harder while still remaining communicative and allowing weight transfer when you really want it.
Whereas many riders utterly avoid the front brake on descents, now it's a more viable option, and on dusty corner entries over bumps our linkage front allows much harder brake application while maintaining far better contact with the ground (bump compliance on linkage fronts is a revelation). It's one of the main reasons we pursued this design, and we think Mr. Duckworth would approve.
We really hope you'll demo a bike with us next year to see for yourself.
There's no real incentive for frame makers to work on linkage forks, the big names have no incentive to be the first to tackle the problem, it's a big investment for uncertain returns. Bad business. The smaller companies certainly don't want to go near this, even if they succeed they fail; if there's real promise and a market for the product, a large company will piggy back off of their work, maybe avoid a patent with their own RnD, maybe just duke it out in the courts, or maybe, just maybe, actually pay.
The only hope for linkage forks is a smaller company like this, but it seems to me there is a high chance of going bankrupt during the process, or even afterwards; so much RnD is going to be inherently expensive and result in a product that some consider has too much personality, and most consider an unknown quantity, and it will cost a lot.
This company looks to me like something designed to showcase a concept, sell a tiny number of bikes, and hopefully be bought up by something larger for the RnD value, patents etc. But to be honest I expect it to go under, then some big companies to aquire the patents and do nothing useful with them.
Even as (if) linkage shows itself to be superior in DH or Enduro WC, it will be prohibitively expensive initially for a slight performance increase that a tiny segment of MTBers actually need/want/will notice, vs the already super developed normal bikes. Uptake will be very slow, development will be ongoing and probably won't be covered by profits. The fact that a company have a superb bike that even dentists can't afford isn't really going to boost their bread and butter sales much. In the grand scheme of things consider that even SLX isn't a very significant product in terms of overall company profits and XTR (from what I have heard) isn't even necessarily covering costs (but at least it shows what is possible, can be trickled down to improve cheaper products, and creates a good image which helps bread and butter profit products to sell (at least XTR shifters RDs cranks etc are similar in form to other shifters RDs and cranks, unlike the fork vs linkage fork).
There isn't even the incentive to secretly develop a WC winning linkage machine then blow everyone out of the water for a few years since 1) you need an extremly capable rider anyway 2) UCI will probably ban it if something like that happened. 3) Even if UCI accepts it and you do it, a lot of potential for negative image and views of your company for doing it (especially if most of them can't afford it, and given that people have little time left for "innovation" after all the recent non-standards crap), from the very people you're trying to get riding it.
You will be amazed to discover how many capable designs were not commercially successful because of their looks.
At our days, it seems that anything that does not look like a session (or have 3 water bottle mounts), has to be destroyed. This is quite unfair. Just give the chance to those designs to evolve, mechanically AND aesthetically.
To support my position I will also add this:
For those (especially spoiled brats) who were not there, when our sport started, when the first suspension systems fought their way to the norm (and fought really hard), just do that following 3:
1) First run a search on the magazines of the early mountain bike era. You will be amazed to discover that there was a very negative stance over suspension forks and even more over full suspension bikes! If the frame was consisted by wider tubes than the (back then) norm, it was an abomination, it had to be killed with fire…
The first suspension fork companies had to fight their way against all these “experts” ho were judging looks by their… roadie tastes!
The same people now, at the same places (as… experts) are defending the same aspects that were rejected by their expertise back then… (WOW).
2) Then. Take a minute and check the early suspension era on mountain bikes. All the much known label products started with problems. Early Marzocchis were dripping oil everywhere! (The joke was that you may find were a Marzocchi went by following the oil drips!!!). Rock Socks were exploding their suspension leg ups (made from plastic), and had to deal with temperamental elastomer units. Manitou had to deal with their own problems and so on….
All those, dependable now, products had a rough start with lots of problems and lots of rejections from the, so called back then, exerts…
The same principle applies on all the aspects of modern mountain bikes! Check the chaos or the early geometry issues. If you check carefully, you may find here and there voices telling that the long (and very acceptable back then – always by the “experts”) stems are not the way to go! Some people (I am one of them) were ridding longer bikes in order to use a very short (and hard to locate) stem! Make sure to check how gradually the stems got shorter and shorter, because of... what?
3) Now take a minute (or as long as you need) and compare the time and effort it took (and the money) to perfect the telescopic fork of today. How many companies, aftermarket manufacturers, versions of products, models, etc., to reach today’s standards. And how those standards, even the aesthetic ones, changed along!
IMAGINE now, if the same effort was directed towards the link forks! How many, different and refined designs we would have now to choose from.
Also.
I’ve seen that many people compare the Whyte bike with today’s bikes, in order to ban it! But if you want to be honest you have to place this product among the competition of that era. You cannot blame this wonderful fork by the frame’s geo!
Valid concern! Between the wheel and wide handlebars, that region is remarkably well protected. Mike managed to hit a tree sideways on his test ride and left a core sample of a tree embedded in the stem bolts, but the linkage is fine; not something anyone else managed to do in years of testing, so thanks for the additional data point, Mike!
As long as it's intact, the steering will be fine. Any product can fail, of course, and we don't want to see your ride cut short with a nasty failure, so we've made the links almost twice as wide for the final version. Far wider than we think is necessary, but it adds only a couple grams and it looks as burly as the rest of the bike!
It should, but we'll have to confirm. None of us use a vertical mount rack and we hadn't thought about it. Thanks for pointing it out!
But if this does work, servicing a shock is way easier than servicing a fork.
Not only is servicing a shock easier, but this shock has one of the lowest leverage rates on the market and less force on it, since the front wheel generally experiences less load than the rear. The service intervals on our front shock will be particularly infrequent.
That being said I don't think this will fork will become accepted unless they invest some proper money into sponsoring some of the best riders.
Once you see the pros compete and do well on these things everyone will want them. The people will ask for them and other bike companies will jump onto the change because they see they can make money there. Most bike companies have their focus on making money and not improving the quality of bikes in general.
But as long as Structure Cycleworks doesn't sponsor several of the best pro riders, this will always stay a very small niche market.
For the average rider this will be nothing more than "I once saw some dude ride on the trails on a very weird bike"
Can't promise we'll be at Interbike, but let's try to connect some time. Drop us a line and let's chat - it's always a pleasure to talk to fellow start-ups and innovators!
It's nice to see so many people appreciate this niche of design history!
Haha I don't know man, you've never seen me ride. ????
I do like you mentioning custom water bottles however, and I'm suprised no other company has come out with one yet. It surely can't be impossible to get a custom size/shape bottle for a space in a frame. If it's possible to get a tightly toleranced carbon fibre frame manufactured, surely it's not too hard to get a funky shape hollow plastic shape made with provision for a screw top to use already available bike bottle tops.
I am keen to see how this bike pans out, the proto looks very smart and even if the looks upset some people, better is better.
bimota.it/en/?p=119
There is plenty of perfectly functional direct sales bikes that everyone knows and will buy at the price they are happy with. However this is completely unproven and untested bike trying to be sold for the same if not more expensive amount. If your going to charge the same amount or more for what we all know as perfectly functional and reliable bikes then why would I want to invest in something I know nothing about based on 1 review?
But how is this not conflicting with the Hossack patents? www.hossack-design.com
Or have they run out?
Great idea! We'll try to get one from the blue bike, even though it's a non-rideable rapid prototype. For now, try this:
www.instagram.com/p/BXx_WvQBArH
But I don't think this is the answer.
No one has ever detected feedback delay from the front tire getting caught in a rut on our prototype alloy bike. On the other hand, a telescoping fork presents a big, deflecting moment arm that definitely does allow deviation of the axle from a rider's desired steering angle. We've all felt it, particularly on long-travel forks; we're just used to it.
The test we will insist on passing is this: If you hold the front wheel of a Structure bike between your legs and twist the bars back and forth, the linkage system should deflect no more than a telescoping system in which one leg attempts to lengthen while the other tries to compress. In fact, we're shooting for less deflection than in a telescoping system, which is why we use such large surface areas on the control arms and TT and a double-crown fork. Carbon fiber is definitely the right material for our bikes; we'd never argue otherwise.
1. The face of the guy riding the bike in that first photo pretty much says it all.
2. So pretty much THIS? www.youtube.com/watch?v=Z37PR0-kdhA
We remember it! We commend Whyte for taking a risk and we thank them for what their efforts taught us.
The Whyte is one of the reasons why we don't have a spherical bearing in the main load path. It also illustrated the value of using the flexibility of a front linkage to focus on dynamic stability, rather than going for ultimate plushness. The smoothness of using bearings in the pivots already addresses that, freeing us to pursue the much more important goal of increasing stability under load.
The linkage on the blue prototype is already stronger than we believe necessary, but, just to give a visual impression of strength, we have increased the spacing and diameter of the steering links by over 50%.
Enjoy your test ride!
www.pro-bike.it/wp-content/uploads/2012/02/Cannondale-concept-bike-Alex-Pong.bmp
Is this a similar idea to how the struts work on Subarus?
Sincerely,
An curious, yet ignorant human
You'd think a truly impartial 'review' would've given that kind of info
The final version is still being drawn, so there's nothing to weigh, I'm afraid. For now, let's say weight will be on par with our enduro segment competition. More accurate numbers will be provided in the coming months as we finalize the lay-up.
I give a lot of credit to Mike and Pinkbike. Several cycling industry journalists have walked past us without even asking a question. Mike jumped at our offer to check it out and insisted we don't tell him a single thing, to ensure he could ride it without any bias or expectation. Friendly guy and super professional. I've always felt his reviews were among the most honest in the industry and I have more respect for him than ever.
When the time comes for a thorough review of the final product, I can only hope every reviewer is even half as passionate about his or her job.
www.youtube.com/watch?v=Pw9gaEiQAxY
There will be an eccentric to adjust the support vs. plushness feel and it's not impossible to create a couple different lower head tube units. We'll consider it!
- Looks a bit dweeby
- Linkage joining the bars to the fork looks kinda flexy. Steer one way, go the other.
We're working on the cable routing. It will be even cleaner on the final bike!
That's true, but it's quite a different situation. A shock has much less bushing area and shorter stroke, but the real difference is that a shock doesn't have an enormous bending moment on it while it's trying to slide.
Who am I kidding?
NOPE
[I'll copy what I wrote elsewhere]
We remember the PRST-1 and PRST-4 and we commend Whyte for taking a risk and we thank them for what their efforts taught us.
The Whyte is one of the reasons why we don't have a spherical bearing in the main load path. It also illustrated the value of using the flexibility of a front linkage to focus on dynamic stability, rather than going for ultimate plushness. The smoothness of using bearings in the pivots already addresses the latter, freeing us to pursue the much more important goal of increasing stability under load.
Just as the telescoping mountain bike fork has come a long way since the RS-1, the front linkage has evolved since the pioneers!
We understand your service concerns. We wouldn't want to work on our own bike if it was as bad as you think!
All frame pivots will have easily serviced bearings. Pull out the through-shaft and punch them out from the other side. You can probably have all of them replaced - if you even need to, as they'll last quite some time - as quickly as just a couple bearings on a frame that requires a blind hole bearing puller!
www.bikeradar.com/mtb/gear/article/mtb-tech-fails-50572
... if we all decide in the FUTURE we want to look f*cking ridiculous while riding our bikes then it totally is the Future
Reminds me of Mr garrisons " IT " from south park! Nope I'm good, don't even care what it does sorry!
Team- "But sir will this generate sales?"
Team Leader- " No, Just a Pinkbike Article!!"
Team- "Brilliant idea sir"
lmao
must have been downvoted by the Homers working for the company
And since nobody will actually buy this and use it, I'm not even going to start talking about the dinamic loads on the bearings that will lead to premature wear much faster than in any rear suspension.
P.D. I tried finding some information about the competittiveness of their enduro bikes in the enduro world but had no success, maybe you can help me out? Anyway, BMW also used cardan transmissions in some of their bikes, and time has proven that design to be inferior, so I really hope nobody uses that as an argument when some dipshits design a bike around that concept.
It may not be able to handle the necessary torsional loads or it may surprise you. I don't see a whole lot of difference between the length of the front linkage vs that found on the rear of a bike, however I do concede that the front of a bike sees different force vectors than the rear.
I may be a lowly geologist, but my father is a mechanical engineer with several patents to his name with respect to designs for cantilevered actuators and hydraulic lifts who sees no major challenges in creating a system that shows very little loss of stiffness in the vectors that forces are expected at the front of a bike when compared to a traditional telescopic fork. Keep in mind, longer forks are more flexible than one would think. The major loss in stiffness would be along the longitudinal axis of the bike, not the rotating axis of the steering system. Wheel deflection on a 29er would produce similar loss in stiffness when compared to a 26er and they don't seem to have insurmountable handling characteristics.
P.D. not every single idea has to be embraced for the sake of it, especially if there are so many arguments against this one. Let people be sceptical, instead of embracing inventions without questioning them. Too many "revolutionary ideas" in the mtb industry have failed miserably, and have cost investors and riders too much money
Torsional stiffness has been a huge consideration for us! The fork is a large, hollow, carbon double crown and the steering links take very little load. Your stem will spin on the steerer long before the steering links flex appreciably.
A telescoping fork with its long legs, bushings, and loose tolerances (any tighter and the fork couldn't slide) isn't exactly optimized for torsional stiffness. I don't suppose I'm going to convince you that our design can have considerably *greater* steering precision and feel, so I can only invite you to try it when it's released!
what you really say, is that you are not interested to be informed about anything (really) new at all!
But,
This is the right place to get informed about the "new" & experimental. Without guys like them nothing that you ride today would actually exist... (think on this for a day or two).
And,
i will repeat what i wrote above. If you were there, at the time that the suspension forks fought their way into... acceptance, back when the full suspension bike concept had to deal with fashion nazis who wanted curved thin steel (and rigid forks), the disk brake was considered to be a motorcycled trend, then you would be able to understand. You found all those ready and well developed, in such a way that all these are your norm...
Give these guys the credit they deserve. Without them you would be ridding a very different (& rigid) bike!
I didn't say "this specific linkage design", I asked how many MX bikes had linkage forks - any type of linkage design, I wasn't limiting to this one.
The answer is the same though. None.
If we're going to look at absurd comparisons to MX bikes let's go a little further. Why do we bother with more complex rear suspension designs when all motocross bikes are either linkage driven single pivots or direct-mount single pivots? Why do we not see water bottle mounts inside the frames of dirtbikes? Why don't mountain bikes have ultra wide rear tires when compared to front tires? Why do we bother with handlebar shifters when clearly foot shifters are more effective in MX?
What I'm getting at is that you clearly aren't thinking things through to their logical conclusion. Yes, dirt bikes are the motorized cousin to mountain bikes. But there is enough different about them that direct comparison is silly. Also, one linkage is not equivalent to another and to suggest that "any old linkage" should be considered shows an obvious lack of understanding in basic engineering principles.
It's just so obvious now, all other designers will be kicking themselves for being stuck in that old front suspension paradigm box...
Where do I invest, it seems like some a commercial solution I'd be a fool to miss this opportunity.
Some people are forward thinkers, others are sheep. Forward thinkers are often wrong, but at least they try something. If everyone was like you, we'd still be waiting for random lightning strikes to start our fires for us.
Geez, that seems a little harsh. I guess the good news is that every other negative comment now seems pretty tame.
Quick Google yielded: i.ebayimg.com/00/s/NzY1WDEwMjQ=/z/AM8AAOSw1S9WgSkA/$_86.JPG
This is by far one of the most hideous looking bikes I have ever laid eyes on.
I really don't see a breakthrough in innovation here
Hahaha
The same people who once wear fluo tights (because they were in fashion), now wear wide, parachute-like shorts and ride bikes that were considered in=motorized motorbikes...
With all this negativity we are just doing circles.
Damn!