Seems it’s the summer of strange forks, first with the new Cannondale Lefty Ocho switching to a standard single-crown design, then the Motion E18 Leaf Spring long travel fork. Now, there’s the Adroit Cycleworks Linkage Fork, and it’s quite the story.

Co-devleoped between Avid Essentials and Adroit Cycleworks, the Linkage Fork’s current iteration has been in development for about two years. There was a version before, but it wasn’t as fully featured as this model. Avid Essentials popped onto our screens earlier this year with their clever retractable bike rack, and brought their expertise in long-travel Jeep suspension designs to the table. Adroit Cycleworks co-founder Aaron brought the bike industry knowledge and carbon fiber construction experience. Together, they came up with a design that promises no stiction, excellent stiffness, and massive tunability.

Why use a rear shock up front?

Adroit Cycleworks Linkage Fork uses a rear shock and parallelogram arms to give you less stiction friction and more tuning options for long travel trail and enduro mountain biking

From a performance standpoint, it’s moving on high quality sealed cartridge bearings at all of the pivot points, and shock pivots run on stock DU inserts (with a bearing upgrade kit available). The benefit is that there’s virtually no stiction, particularly when actually being ridden. But even in the lab, they say without any shock pressure, the weight of a single piece of paper is enough to get it moving. With traditional telescopic forks, not only do you have the friction from the seals, but also drag as fore/aft forces press it against those seals and bushings. None of that applied here.

From a tunability standpoint, they really liked the performance that a Fox FLOAT X2 shock has, and it also has a wide range of high- and low-speed compression and rebound damping. You also have the inhering tuning available through air volume and pressure adjustments. But that’s just the beginning. By altering the shock length and stroke, you can dictate the fork’s travel and height. Move an adjustable linkage and you can tune the progression.

How the Adroit Linkage Fork works:

Adroit Cycleworks Linkage Fork uses a rear shock and parallelogram arms to give you less stiction friction and more tuning options for long travel trail and enduro mountain biking

The design uses upper (green) and lower (yellow) control arms, similar to a most vehicles’ front suspension. the lower shock mount is attached to a shock linkage (blue), which is connected to the upper control arm (green) via a small link (pink).

As the legs move up, the upper arms pull the shock linkage upward to compress the shock. The upper shock mount is fixed onto the included/integrated 32mm stem. The whole thing fits into standard 1-1/8″ to 1.5″ tapered steerer tubes.

Adroit Cycleworks Linkage Fork uses a rear shock and parallelogram arms to give you less stiction friction and more tuning options for long travel trail and enduro mountain biking

The lower steering assembly (red) looks big, but it doesn’t protrude rearward anymore than most big long travel single crown forks. So, if your frame fits a Fox Boost 36 or Rockshox Bluto, they say it should fit this fork. Yes, it looks like it extends farther back than that, but imagine spinning any fork all the way around. If the crown of those forks would clear the downtube, then this should, too.

Adjusting the travel

Adroit Cycleworks Linkage Fork uses a rear shock and parallelogram arms to give you less stiction friction and more tuning options for long travel trail and enduro mountain biking

The fork is designed to be flexible. Not flexy, but rather, adaptable. Stock configuration will have 160mm travel with a 200×57 Fox FLOAT X2 shock. Because it has an almost perfectly linear path, though, all you need to do to adjust the travel is change the size of the shock.

Want 170mm travel? Get it with a 215×70 shock. Want to drop it down to 140mm? No problem, just throw a 165×38 in there. Keep in mind, adjusting the travel will affect the height, so if your bike is designed around a specific fork length, changing it by too much off that intended spec will probably throw your handling and geometry off. You know, same as with any other fork. The mounts are designed around Metric shocks, but you can use non-metric shocks by adding spacers.

Tuning the fork

Adroit Cycleworks Linkage Fork uses a rear shock and parallelogram arms to give you less stiction friction and more tuning options for long travel trail and enduro mountain biking

Two versions of the Linkage fork will be offered, the Base and the Premium. Base version has fixed leverage ratios and dimensions to make it an easy plug-and-play upgrade for  most 160mm bikes. It has carbon fiber legs, control arms and linkages, but sticks with an alloy crown and shock link. It’s moving on standard alloy and steel hardware. Claimed weight with shock is 1,895g (4.18lb), and retail is $999. Available for pre-order now, they say they should ship by end of June. After that initial launch, the price will remain the same, but the included shock will likely be downgraded to a DPX2. The upside? The next revision might chop another ~45g off the design. On the Base model, adjustments are limited to changing the shock’s size and using the shock’s built in damping and air adjustments.

The Premium version upgrades to a carbon upper crown, titanium hardware, and an adjustable shock link. This is where it gets more interesting because by moving the upper or lower position of that shock link, you can change the ramp. If it’s slanted more, it gets more progressive. If it’s more straight up and down, it becomes more linear. They say the leverage ratio is 2.6:1 when perfectly linear, but can go down to 2:3.1 by fiddling with it. Claimed weight for the Premium Linkage Fork with an X2 is 1,655g and retail is $1,499.

The fine print

The fork is designed for 29er and 27.5+ Boost wheels and tires. They say you can run a 29×3.0 (aka 29+) as long as travel doesn’t exceed 160mm. Actual travel range is 140mm to 170mm, which corresponds to equivalent travel telescopic forks. It needs to run on bikes with head angles between 67º and 62º. It’s only available with a 51mm offset for now, but they’re working on a 44mm offset for the dual-arm forks to work with bikes like Transition’s Speed Balanced Geometry (and all the other modern trail/enduro bikes with long top tubes and short stems).

But wait, there’s more!

Adroit Cycleworks Linkage Fork uses a rear shock and parallelogram arms to give you less stiction friction and more tuning options for long travel trail and enduro mountain biking

Want to go even lighter? An upcoming Single-sided version uses an L-shaped insert that’s bonded into the lower leg with a standard 15mm thru axle extending from it. Slide your wheel on, then install the special nut on the outside to secure your wheel. That nut is spring loaded, too, so once you reach the recommended torque setting, it’ll prevent over tightening. It’s a clever design that lets you keep using your standard 15mm thru axle hubs, no need for a special “Lefty” version. Current weight of the late stage prototypes is 1525g, mainly because that axle system adds a good bit of weight to be strong enough, but they’re targeting closer to 1,400g or less by the time it’s available in August. Planned retail is $1,199 with the X2.

And that’s not all…

Adroit Cycleworks Linkage Fork uses a rear shock and parallelogram arms to give you less stiction friction and more tuning options for long travel trail and enduro mountain biking

With a perfectly flat compression ratio (it stays at about 2.6:1) and linear rate with the intended shock, it’ll allow for the use of “donor” shocks to an extent. Translation: While it’s designed around a 2017-18 Fox Float X2 with a stock tune, you can put other shocks in there with minimal impact to the rate and ratio. The benefit to this isn’t just versatility, but also cost savings. Search eBay and the forums and you’ll find plenty of lightly used or even new shocks that were taken off new bikes when the user upgraded their own rear shock. So, when (if) they start selling it without an included shock, you’ll have options.

One last benefit? Easy serviceability. Just clean the shock or pull it off for service, there’s no fork internals that need to be accessed. And if one of the parts breaks in a crash, you can just replace that one single part, not the whole fork.

They say they’ve subjected it to every UCI test, and it’s passed. They say it’s a lot stiffer than most, on par with a Rockshox Boxxer World Cup fork. And they’ve spent plenty of time trail testing it, running it into curbs and more. We’ll be getting one in for long term review to see how it works.

AdroitCycleworks.com

66 COMMENTS

        • They claim that it doesn’t protrude any further rearward than a boost spaced single crown spun sideways, but there are frames out there that intentionally don’t clear those crowns and use a steering stop, instead. On those bikes, this fork is a no-go.

          Pretty interesting that the single leg fork can use standard 15mm hubs.

    • It says very clearly the claimed weights are with a shock.
      Even if they weren’t, figure 400g for an X2, still would put it around 2kg, on par (if not slightly less) than any other 170mm 29er fork available.

      • Well, that would be for the Premium fork not the standard that is already at a weight comparable to a long travel 29 fork. The 1655 figure is very low, lower than a Formula 35. Hard to believe, but great if true, with all those linkages and a length basically equivalent to a double crown fork ..

  1. That looks really cool, but I like weird things and don’t care if it matches the logo on my socks. So I

    One thing I don’t see mentioned anywhere (their web site has much less info than here): with the integrated stem, there’s got to be a limit on head tube height. No mention of what that limit is or how you’d mount it if your head tube is shorter or even how you’d adjust the headset – since the stem is part of the fixed link in the linkage I’d imagine you wouldn’t preload the normal way.

  2. I don’t get it. Motorcycles have been using the traditional fork for years with no problems. Their industry is also MUCH larger than bikes = way more engineering, R&D money, etc spent. So how come you don’t see weird gimmicks like that on those bikes?

    • performance doesn’t really matter. as long as it’s wacky and expensive, people will buy it (see also: lauf). this thing might not be terrible, but reading the copy is galling.

      also UCI tests, lol.

    • There are enough engineering texts in the moto field that show the distinct advantage of these sorts of forks over telescopics but like the cycling industry, the latter are so entrenched that to move away from them would require a paradigm shift in the industry and manufacturing. BMW is using a version of this on many of their bikes but they have always more or less had an enclosed design/manufacturing system, and you can find plenty of examples in the custom/small scale production area. I like the idea for all sorts of reasons, especially if they have it worked out properly but at that cash…….!

    • Telescoping forks on motorcycles are full of problems. The industry accepts them and the riders don’t know any better..

      • Everything is full of compromises. Linkage front suspension can be heavier, harder to package within a desired wheelbase, not as stiff (from a steering standpoint), costlier, more maintenance prone, etc. Its better than telescoping forks in other areas. There is rarely a universally better solution.

        • Linkage forks are stiffer for steering, lighter weight and have toe potential to be much easier to maintain with the same pivot hardware we’re using on rear suspension today.

    • Also don’t forget motorbike are heavier and faster Sotheby’s chassis is much harder to move hence the easier/better suspension tracking even with more friction. A test showed for example that a downhill bike should not be too light to get best suspension tracking. Also most ebike testers say the suspension track better.

    • A motorcycle weighs much more than a bicycle and has a much bigger power plant (hard to compare hp but a cyclist would be around 0.3-0.5hp). Friction on the seals, weight penalty versus manufacturing costs, speed etc. are massively different. It would be similar to postulating that as big rigs use air-brakes therefore we should put air-brakes on passenger cars.

  3. I always get every excited by parts that have limitless adjustment options! So many ways to get lost in the woods…

  4. Service is easy, just remove the shock and SERVICE it. Huh? A Float X2 takes special tools to even open the air can, let alone replace the air seals(not sold separately, not possible to service without overhauling the damper). Who do they think they’re fooling? At least a cartridge equipped fork can be serviced with only a few simple tools.

  5. Looks goofy, might work well. I have a couple beefs- I wish the axle path were more J-like, or at least more tunable. And if they’re going to do a one-sided version, I think it would be smarter to go with a 20mm axle.

    • Did you have a Girvin? The J-Path was good on flats but bad on steeps because front-end suddenly tightens up right with you hit a bump pointed downhill … over you go!

  6. Neat idea for sure but I don’t understand what problem this solves…can someone help me out? I’ve never heard someone on the trail complain about stiction or their steering lock being hindered by a traditional fork.

    • Back in the day (say, 1994 or so, so quite some time ago), traditional forks had quite a lot of stiction and flex. Linkage forks competed with them by virtually eliminating stiction and flex. They really did have a lot to offer compared to telescopic forks. But then traditional forks beefed up- they got bigger stanchions, one-piece lower leg-brace assemblies, bigger steerers, and thru axles. And so the need for linkage forks shrank.
      Still, modern iterations of traditional forks have some stiction and flex. I do wonder if the Adroit fork or any other modern linkage forks offer much of an advantage over, say a Fox 36- or if ordinary forks have developed so much that linkage forks or that they’re just for people who want to stand out from the crowd. At the SRP they’re asking, I won’t soon find out.

    • Depends on what your def of a problem is. Linkage forks keep a near consistent head angle as the fork cycles through travel. The wheelbase stays relatively the same too, and that’s more important in this day of LL&S (Long Low & Slack). The slacker the bike is the more pronounced of a change the shortening wheelbase provides as the fork cycles through its travel. And again with an issue with LL&S bikes these days, bushing bind and wear are more pronounced. They’ll need to make it compatible with head angles under 65 soon though. One final bit, it should dive less due to brake forces. Telescopic forks today are pretty damn good, but a linkage fork has the potential to outperform one if designed right.

    • Yup had one, it sucked, the HA actually got steeper during compression, I had some nasty OTB’s on that bike. The rear susp was good tho

        • But they don’t have to. Theoretically this design could move the wheel forward through its stroke, negating the geometry change due to compression alone.

          • No, that’s not possible. Rear suspension compression is the only thing that negates a change head angle during a front compression. So on a hardtail, the head angle will always change during compression.

            • The headtube angle on the frame will always change on a hardtail, but the theoretical angle could be kept static. Just have the correct forward axle path on the linkage fork.

            • entirely possible. for an extreme case image the top link of this design removed and replaced with a single pivot. The wheel will move outward as it compresses. Rake and trail will increase, for intents, making the effective HTA slacker

  7. I’d like to see a wheel travel path diagram, or better yet an articulating cad rendering. The original Girven looked cool when it came out, but actually racing on one really sucked. The problem was that the wheel moved backwards as it progressed through its travel, which would land you on your face if you went over anything larger than a log. Hopefully these guys are old enough to have ridden old technology like this and not just have seen one in an old magazine that they thought looked cool.

    • Given the shorter upper linkage, it would seem this could in theory maintain effective HTA or be tuned to decrease it.

      • How do you define “effective HTA”? You could tune the fork with a forward or vertical axle path to maintain Front Center as it compressed, but that wouldn’t maintain the HTA, and would eventually lead to a Trail measurement that became negative, no? Maintaining the front center would be good for stability and weight distribution, but negative trail would be bad for stability, so you would be robbing from Peter to pay Paul.

        • You are right, trail would decrease, but not necessarily negative. The issue will be the weighting between increases in wheelbase due to rake and the effect on trail – all in comparison to a standard fork.
          I’m not even sure it’ll be better in actual ride conditions, just that the design allows for that tuning capability compared to a standard telescoping fork.

  8. The big advantage to a linkage fork like this (besides vastly reducing stiction) is that your wheelbase remains stable under dive greatly reducing pitch sensitivity and perhaps reducing our need for these modern chopper style head angles. One of the downsides is that pivots get loose and have to be serviced a lot more than fork bushings. Normal forks need regular oil and wiper service. It certainly looks more promising than that Lauf (?) that was shown the other day. That didn’t look like it would survive your first 3′ drop much less a regular beatdown.

    I love this fork and I would be ecstatic if it performs up to par. But I have to be honest the weights seem optimistic to me for so much more going on than a slider fork which then causes me to question the other claims. I’ve been burned enough to not be an early adopter but its the first linkage fork that actually looks robust and well thought out and I look forward to the reviews.

  9. I wonder how the left(y) front tire is removed with the brake caliper mount. Is it similar to a cannondale lefty? Otherwise, Adroit take my money already!!!!

  10. I always loved my Noleen ELT. I am not to happy about the integrated stem though. I am very sensitive to handlebar height and reach, would like tuning options here.

  11. Honestly this is awesome. Reminds me of a modern Girvin , i want one, now . Bored with traditional forks.

  12. Given the different length linkage arms I’m assuming it decreases effective HTA as it compresses. If so, pretty nice. Not sure how it rides though. For example, BMW’s telelever works great but has a vastly different feel which isn’t always the best.

  13. whatever else, the 15mm “thruaxle” in place of using a Lefty hub is dumb as shit. I get why, but if Cannondale had done the same they wouldn’t be selling them anymore. The Lefty stub axle is 25mm at the leg and tapers down to 15mm, and that’s part of the reason people who like Leftys actually do, because the single sided axle was properly thought out.

    • Yes I’m very surprised it passed all test. There is some serious bending moment in here. Even if the axle is super strong steel it will bend. Lefty hub was the smart choice.

    • They didn’t really give details on how the fixed axle transitions into the leg as it leaves the wheel hub (its not just a 15mm TA bolt through based on the article). Hard to say it its actually weaker without looking at the design and the axle itself. Pedal spindles are less that 15mm…although those are known to break

      • Ok, i reread it. The same structural problem exists. The axle has to be 15mm straight through the hub as it’s designed to work with standard 15mm thru axle hubs. That thing is going to be a noodle, and the disc is going to rub the caliper.

        • No you are assuming the moment reaction point is also 15mm. It may or may not be as no details are given. The attachment may flare up to a much larger diameter as it transitions into the fork leg.

          • It absolutely has to be. A 15mm thru axle hub will not accept any larger. The reaction point is the disc side bearing.

            • The torque reaction point is where the axle connects into the fork.
              That said, to keep it tidy, one will tend to need to increase diameter in the hub, hence C-dale’s design.

  14. I wounder about shock tuning and seal friction. Remember that most of a rider’s weight is on the back of a bike, approx 40/60 to 30/70%. Rear shocks are designed for higher pressures (stronger air seals) and higher loads (increased damping). It’s hard to imagine that simply lowering the air pressure is going to make a rear shock ideal for a fork. It’s not like they’re over-leveraging the shock to make it plusher.

    Even if everything else is dialed in, it might need a special, low-pressure shock to perform its best.

    • That’s just ridiculous, Pete.

      Where is the need for a ride report, when you have nearly infinite quantities of conjecture, armchair engineering, and nay-saying available.

      You really should have known.

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