And the award for most interesting bike at Crankworx Whistler goes to… Structure Cycleworks! Based in Calgary, Alberta, this upstart company has decided to do away with telescoping forks in order to create a bike that theoretically offers better stability and control when you need it most.

When a traditional fork compresses it reduces its available travel, shortens your wheelbase and steepens your steering angle. The (yet unnamed) Structure bike acts in the opposite manner- As you brake and/or compress the suspension, the front end resists brake dive, the steering angle gets slacker, and your wheelbase is maintained.

I was lined up (and deathly curious) to ride the prototype, but unfortunately another journalist smashed it into a tree and broke the fork! While we can only speculate on how it might ride, I can at least explain the creators’ thinking behind the concept…

Structure Cycleworks, prototype with team

The prototype seen above has been tested for three years on various trail networks across North America, and all its pivot locations are adjustable so the designers could fine-tune everything as they went. The blue carbon framed version is still just a mock-up of a production model, so some areas of the frame will see refinements before consumer-ready bikes are made. If all goes well, they’re hoping to hit the market in 2018. The carbon frames will be manufactured in Asia, while hardware and injection-molded parts will be made in Canada.

Structure Cycleworks, front end close up

Structure Cycleworks, front end compressed

The obvious eye-catcher on this bike is the front end. It’s hard not to notice the linkages, the missing head tube and steering link that connects the bars to the fork. Engineer Ryan Rasmussen says by using bearings and pivots instead of two seals and stanchions (which are constantly producing friction), the Structure’s front end is highly active and smooth. A Rockshox Super Deluxe rear shock provides six inches of travel from the front end.

 Structure Cycleworks, fork, frontStructure Cycleworks, fork, behind

The fork is a rigid carbon dual-crown unit, and as you compress the suspension its steering angle slackens by 6 degrees. Rasmussen says his design resists brake dive better than a telescoping fork, leaving more travel available, and because your wheelbase doesn’t shrink you don’t sacrifice stability when it’s needed most.

Structure Cycleworks, rear end

Despite its normal appearance the rear linkage on the Structure bike received just as much attention as the front. The rear end is a horst-link design which offers six inches of travel, handled by a second Super Deluxe shock. The ride tuning is all about the pivot locations, which are slightly altered for every different frame size…

Structure Cycleworks, front linkages

Structure Cycleworks believes a bike should be built around the rider’s center of gravity, so on both the front and rear ends pivot locations will vary. This ensures a shorter person with a lower center of gravity (and usually lower body weight) will get a more linear linkage that requires less leverage to become active. Larger frames will be more progressive leverage-wise, so top-heavy riders don’t just blow through travel and suffer poor pedalling performance.

The bike is definitely unique, and so is Structure’s sizing system. Three sizes will be offered, but all frames will feature cuttable seat tubes to offer more height adjustment within each. The idea is that riders can choose their frame based primarily on reach preferences, however this seems contradictory to the idea of suspension-tuning each frame size to best accommodate its rider.

Structure Cycleworks, rear angle

While this complex bike looks heavy it actually isn’t- Structure says the frame weight is mid-market, and they expect complete builds to come in at around 30lbs. The price tag, however, gets a bit heavy. While MSRP isn’t yet decided, the cost of a frame is expected to be about $2000 over most other top-tier frames.

Does all this raise a few questions in your mind? Check out Structure Cycleworks’ website for further details.

structure.bike

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56 COMMENTS

  1. That’s a $2000 premium that includes the fork and front shock, right? So more like $1000+ once you add a fork to a Trek, Ibis, etc… frame.

    • Hi dockboy,

      We’re still working out final pricing, but I feel it’s only fair to correct this unclear phrasing. Expect it to be a $2000 premium overall.

      I’m working on some creative component spec options from smaller vendors that will offer an excellent balance of value and performance. We want as many people as possible to be able to get on our bikes and see for themselves how well this integrated chassis rides!

      Another way we add value is our money-back guarantee: Ride it for four months (for the first 50 sales) and if you don’t think it’s everything we say it is, give it back. After the first 50 customers, we still offer a two month guarantee.

  2. Interesting the fork broke in a crash. Of course any frame/fork could break by hitting a tree in Whistler of all places, but wonder if it’s more susceptible or fragile then a traditional frame/fork. No way to know at this point. If has a lot more going on w/ many leverage points to fail on a front impact. Again, there is no way to tell until a few of these get in the wild.

      • Thanks for pointing that out, Beat_the_trail. The test mule was a minimalist single-crown. Everything on it was underbuilt, actually, so we could evaluate where the weak points were. This was actually the first thing to fail and it took a direct hit into a tree to do it!

        The final version will have a massive carbon double-crown fork. Had Mike slammed a tree on that version, I’m not sure the tree would’ve won!

          • Thanks, Von Kruiser! Only so many hours in the day, though, so I’ll probably have to check out after today. Always feel free to contact us via our (still under development) website: Structure.bike.

          • Disagree. Ryan is obviously here to control the message and pave the way for future sales. There may be a sentence or two that is helpful but the rest should be ignored. The comments section should be a commercial-free zone.

            • There is no such thing as commercial-free zone: I wouldn’t be surprise if the “competition” starts pointing out design flaws or bad mouthing in the comments sections for the sake of discredit the company. Having an explanation could be useful sometimes

  3. I’d ride it. It could turn out to be the next big thing in full-suspension bikes. I’m thinking there is still some potential in optimizing the steering linkage. It makes me think of a hobby horse though, it would take a while to get over how weird it looks.

    • BMW does something similar for some of its motorcycles and an italian brand also had an even closer design in production some time ago. Those design can be fine on some level and give some confidence to the rider. However, in general for performance the classical forks have always prevailed. On the above design i think the steering stiffness wil be so-so, also it can only be heavier than a regular fork and above all those anti dive system tend to provide less grip on loose sections.

      • Antoine191: I can tell you the steering stiffness is *better* than on a telescoping fork, but I doubt you’ll believe me; when we have some final versions available for demo, I’ll put your name at the top of the list to test one! 🙂

      • but, for BMW’s serious sport bikes, they (as well as every other manufacturer) inevitably all use a conventional telescopic fork. While the traditional telescopic fork has it’s disadvantages, the sheer simplicity of it’s design and function still reign supreme. Linkage forks will always remain on the fringe.

  4. So… 22 or so bearings/bushings/pivots to replace whilst servicing this monster? Rather you than me mate :p

    Cheers!
    I.

    • Cost wise, it could be a value. Not many high end forks allow you to swap out DU bushings once they’re worn out these days, and not many shops have the proper tools to do the job on the forks you can. Cost of a lower leg assembly is way more than the bushings/bearings would be unless you go ceramic.

      • Thanks for pointing that out, Smokestack. We also like to point out that the incremental cost from a mid-level to a high-end bike primarily gains you a little saved weight and some componentry; for another equivalent increment, we offer an entirely new type of chassis!

  5. Neat. I like that people do things like this even if it may not work out for one reason or another. They’ll learn something from it and all designs can be refined.

  6. The biggest surprise to me is that I live in Calgary and I had no idea that someone in town was doing this!…. Kinda cool to see someone trying something new right here in my ‘hood!

    • Hi Jason. There have been many front linkage designs, but ours is very different from the Whyte design – and we thank them for their pioneering work and what they taught us.

      We have moved the spherical bearing out of the main load path an into the low-stress steering load path, as this was a vulnerable point on the Whyte.

      The Whyte also wasn’t the most torsionally stiff, which has been addressed in spades.

      Most importantly, though, Whyte used their aligned the axle path with the bump force vector for ultimate plushness, which caused a dramatic shortening of the wheelbase and instability under load. We are *increasing* stability under load.

      The difference between our design and Whyte’s is greater than the conceptual difference between any two telescoping fork bikes.

    • Lifetime warranty on bearings, myke2241! If your rear pivots can survive, then our front pivots, with even wider spacing and being shielded by the frame and linkage, are expected to be even better!

  7. Structure-Ryan,
    Have you tried an integrated stem-bar combo that would allow wider triangulation of the upper steering yoke (or whatever you call the thing attached to the stem area)? Seems like it would be an easy place to gain stiffness for steering precision.

    Maybe its not needed or will add too much weight, but never understood why these designs don’t take advantage of the handlebar width and the upper fork triple clamp full width.

    • Hi JBikes,

      I’m a big fan of integration, but we want to give customers as much flexibility as possible. Our stability enhancing design enables more flexibility in sizing (ex. you don’t need to size up to your limit and run a 35 mm stem to get adequate stability), so we would have to produce a tremendous range of bars and stems to accommodate all the fit options our design provides.

      Also, the final design will relocate the upper steering link clamp below the upper head tube to shorten the steering links, then the upper clamp and upper steerer will be integrated to minimize weight.

      Best of both worlds!

      • Understand. Don’t get down by all the “tried it before” comments.
        Almost everything was tried before at some point. Execution and refinement makes a big difference. And I’ll always take more options as a consumer!

  8. I can’t recall who did it, but a major brand did a prototype of this basic design in the 1990’s. I remember seeing it in MBA or Velonews Interbike coverage.

    • Hi Jon,

      The alignment between the upper and lower head tubes changes slightly throughout the travel, making a telescoping steerer problematic. Also, the scissor links have lower friction than a telescoping system.

  9. for Structure-Ryan –
    Will you be providing any demo’s at the larger bike gatherings?
    I really like the geometry this offers on paper, but I feel much of your success will be dependent on how it rides and people being able to actually experience it before buying.

    • Hi JBikes,

      We agree and we want to get some demo bikes out in the wild as soon as possible. One thing at a time, though, and we’re currently working overtime to get the bikes produced!

      For those who are as excited as we are about this design, we offer a four month money-back guarantee for the first 50 (two months after that)!

  10. I like the use of pivots over sliders as they really do have less resistance to the initial motion, which is awesome. But I’m a little worried about what sounds like a wheel motion which moves forward as it compresses. This has been tried before with the USB fork and it does undoubtably prevent brake dive, but it also prevents the suspension from working effectively on impacts coming from the front of the bike, as the wheel needs to move backwards to effectively absorb them. And apart from vertical landings from jumps most bike impacts do indeed come from the front.

    • Hi Geoff,

      The wheel path in the most supportive/stable setting is essentially vertical; the more plush setting is more rearward.

      The idea of aligning the wheel path with bump forces sounds appealing and has been tried before, but the consequences to dynamic geometry created far larger problems than what was solved.

      We have been experimenting with the level of anti-dive and dynamic geometry enhancement and we’re really liking the two settings we offer. We agree that some earlier anti-dive systems were overly aggressive, compromising braking traction and impact management.

      Compared to the best telescoping forks, the more aggressive setting is dramatically smoother over small impacts, due to the bearings, and feels similar over most impacts. The only time it may give up a little plushness to the best telescoping forks is on large, rounded impacts when there is zero brake force applied. Under even the tiniest bit of braking, the bending force on telescoping bushings puts traditional forks at a disadvantage – not to mention losing 35-40% more travel to brake dive.

      When using our less aggressive setting, the WTF system feels smoother in all situations, while retaining most of the anti-dive and geometry enhancement.

  11. 15 pivots and associated bearings and clearances. Quality control is going to be a b*tch. Also, it is going to be heavier than the current telescopic forks. All for what? A vertical wheel path? It’s not even rearward like it should be. Basically, this will sell to those with thick wallets and thicker heads. It just doesn’t have any real benefits over current front suspension solutions. It may be a fad, but it in no way is ‘the future of bikes.’

    Actual engineer, not just an armchair one.

  12. Hi Jon,

    From one actual engineer to another …

    QC is always a challenge and this is certainly no exception. We’ve chosen one of the finest factories in the bike industry, which also produces the upper-tier frames for a few companies that make “regular” and “premium” versions. Our design is not the most tolerance-sensitive they produce, so we’re confident they can do it. It’s no more challenging than a rear suspension design and rear suspension tolerances are generally not a problem, so why would this be any different? Also, the spherical bearing in the steering link, which is necessary for our system, greatly diminishes the tolerance sensitivity of the steering assembly.

    Regarding the wheel path: It’s true that a rearward path is more aligned with most bump force vectors, but the rearward path is the main reason for the reduction in steering stability under load that’s inherent to telescoping forks. Some front linkage systems have attempted to better align the wheel path with bump forces and, in doing so, worsened the dynamic geometry problem. The smoothness of bearings, rather than bushings, more than compensates for any loss of “plushness”, allowing us to use a small portion of this “plushness surplus” to create our Stability on Demand dynamic geometry. To ensure we offer the right balance of support/stability vs. plushness, the SCW 1 has an eccentric (similar to a flip chip) that allows the rider to choose more support/stability or more plushness.

    If I haven’t convinced you, take one for a test ride next summer!

    • As a mechanical Engineer and mtber through and through, and old enough to have begun my odyssey in the mid 80s I’ve seen and ridden a lot. I’ve not seen anything particularly exciting for a while. This design has me itching to ride it and let that experience guide my opinion. I’m optimistic.

      • Thanks, rob! You’ll be able to test one next summer or you can get in touch via Structure.bike and put down a deposit to get into The Foundation, our early adopter group that gets a limited edition finish, some Structure bonuses, and a four month money back guarantee!

  13. I actually really dig this, nice to see someone not scared to try alternative ideas and I like the idea of front and rear suspension being part of a single chassis rather than compromising ideas to suite the current fork market.

    I get a tonne of arm pump and I like the idea of a more supple front end and no diving when riding steep trails.

    • Thanks, ali! Chassis integration lets us design everything to work together exactly how we want it. By moving via bearings, rather than sliding bushings, the reduction in friction is tremendous.

  14. Frankly I find it very exciting and refreshing. I see some real potential here. Real Innovation in the industry has been lacking. I’ll be watching this closely.

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