Development Story - Cane Creek's New Helm Fork

Design Engineer Brandon Blakely holds an early Helm prototype. Brice Shirbach photo


Why a Fork, And Why Now?

The news that Cane Creek is entering the high-end fork business hitherto occupied by the likes of Fox, RockShox, Manitou, and Öhlins, all brands with a long history of front suspension behind them, only underlines the mettle that the relatively small North Carolina company possesses. I mean, let's be honest here; when you're thinking about a new fork, there's a pretty good chance that you are only considering suspension from two, maybe three, brands, despite there being a handful of decent options out there. But then again, now that their catalog of Double Barrel shocks covers nearly every type of use, moving to the opposite end of the bike is probably the next logical thing for a suspension company to do, right?

Of course it is, but the rational behind Cane Creek's decision can be easily countered by the obvious observation that the current crop of mid-travel forks don't exactly feel like they've left a ton of room for improvement. That's great for us riders, sure, but it's much more difficult to jump into a mature market for the first time than it is to step into one with room left for leaps and bounds of performance gains. That wasn't the case back in 2012, however, when Cane Creek first started their fork project, but it sure is these days.


Graphic Designer Evan Voss (left) and Brandon Blakely with his dog.


So, how exactly is Cane Creek going to set themselves, and their new Helm fork, apart from their formidable competition? ''I believe in the value of diversity in life, of having variety. I think that while the Pike and 36 are great forks, there are people out there that want something different,'' Cane Creek President Brent Graves explained to me when I asked him that exact question during my visit last summer to see the Helm being developed. ''There are definitely discerning riders that want something different, even if they can't put their finger on it right now. With Double Barrel, it wasn't like people were beating on RockShox's door going, 'Hey, make a shock like this!' But the Double Barrel came out and people were like, 'Wow, now I can do this. I can tune it this way.' That is, I think, what we're going to bring to market; some unique solutions.''



Sometimes a disguise is called for. Cane Creek was able to keep the Helm largely under wraps during its development.


Five years in the pipe is a long time, unique or not, and Graves puts that long gestation period partly down to Cane Creek's 'at ease' pace that, he says, stemmed from the company's rather lucrative Aheadset patent that expired back in 2010. ''Knowing that you had the royalty checks coming in, it tempered the capitalism entrepreneurial spirit,'' says Graves. ''The sense of urgency is not there to say, 'Oh, we've got to get this done on time.' Or, 'Hey, we've got to look into adding some other products, look what the market's doing,' and so forth. We got comfortable. We just can't think, 'Oh yeah, when it's done, it's done,' and so forth. That is, to some degree, what's happened with the fork.''

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Why Not a Twin-Tube Damper?

I would have bet money that Cane Creek's new fork would feature a twin-tube damper and, as it turns out, I would have lost all that money. Instead, it makes use of a mono-tube system that's similar in layout to what's found inside of high-end forks from Fox, RockShox, and everyone else other than, interestingly enough, Öhlins. Even Cane Creek was expecting to use a twin-tube system, and it took a full year and a handful of functioning, albeit rough, prototypes for them to realize they'd have to break away from the damper design that they've become well known for.


Morrison and his team decided that a mono-tube damper makes the most sense in the Helm, but only after a year of testing a twin-tube system.


''Between initial concepts to working prototypes to play with, we probably spent about a year on a four-way adjustable, twin-tube damper,'' Director of Engineering Jim Morrison said of the process that eventually saw them abandon the idea. ''What we ended up prototyping was not a production-level anything, but it was to prove that a twin-tube damper like that would be the route we wanted to go down,'' although it ended up proving the exact opposite. ''We had several prototypes worth of parts, got those put together, started playing with them, and just immediately ran into roadblocks.''

One of the biggest challenges, Morrison explained, was just how complex a twin-tube damper is and how it all needed to be squeezed down into a fork leg. Assembly issues, like being able to have seals and all of the small parts fit inside of each other as intended, proved to be difficult in Cane Creek's own workshop, let alone a service center or even someone's garage.


An early prototype of the Helm's damper opened up.


This had Morrison questioning the feasibility of a production line being able to put out something reliable, especially when multiple part vendors would be involved: ''You could absolutely make it. It would just be challenging. In a production setting, it would present liabilities. It would not be easy to make, but it would be expensive. It would be a complex, expensive part.'' In other words, more money and less reliability for the consumer, which sounds like great reasons to choose a different way to get it done.

So, after investing a year and probably a hefty amount of R&D costs, Morrison and his team made the call to wipe the slate clean and move to a more traditional mono-tube damper. ''Solutions we were coming up with and what we were seeing, what we wanted, like what do you want in a damper, and everything kept pointing us to 'Well, we could do this. We could do that.' It just kind of eroded the twin-tube feature; it took away from the positives of it,'' he described of what was probably a difficult decision.

''If you go back to the initial decision to do the twin-tube damper, why do that? Well, that's because that's what we do. Well, we also make shocks. We haven't made forks, yet. Forks are a new thing for us, so is the twin-tube damper even something you want in a fork? What are the advantages of the twin-tube?''


From the bottom up: a twin-tube damper using the piggyback from a Double Barrel shock; a prototype twin-tube damper made to fit into a fork; a prototype mono-tube damper.


After all that time and effort, what Cane Creek ended up with is a mono-tube damper that uses an expanding bladder as a compensator. Sound familiar? Yup, that's the same basic architecture that Fox uses for their FIT4 damper, and also that of RockShox's Charger damper. This is not a coincidence. ''I would say that things are converging on that point, and I think they're converging for a reason. It works, and you can make a lightweight and very functional system,'' Morrison said of why most suspension companies are coming to the same conclusion. ''You can make it more complicated, but we haven't found a reason why.''

That said, Morrison certainly did look at a few possible ways to refine what is now a traditional and proven damper layout.


The damper's expanding bladder compensates for fluid discplacement, just like you'll see with most other mono-tube systems.


The most interesting of these was to charge the sealed area outside of the expanding bladder with nitrogen, much like how a rear shock's internal floating piston has a charge behind it to provide back-pressure. A few prototypes were built, but the idea was abandoned, again for it simply not being needed, especially because the mono-tube layout doesn't require the same type of back-pressure that Morrison's early twin-tube prototype dampers called for.

''We sat around talking about it, and we couldn't theorize a reason why it would be positive, and our testing has proved out that it essentially didn't do anything except add an additional spring rate,'' something that Morrison obviously didn't see being beneficial for any reason. ''As much as we would love to set our damper apart with them, 'Yeah, we're nitrogen charged and blah blah blah.' If there's no functional reason to do it, why add the cost and the additional complexity? With our damper, our goal is to something that we hope will set us apart because of how we've tuned it. The tune is what we really hope to talk about on the damper side.''


Spot the air valve on the left of the top cap? It was to allow the backside of the bladder to be pressurized with nitrogen, a trick that turned out to not be required.

You're looking at the production fork's damper.


So while the big news, besides the fork itself, is that Cane Creek has gone with a traditional mono-tube damper, they're emphasizing that it's what they've done with the shims, ports, piston, and oil that is going to set the Helm apart; Or, in other words, the fork's tune. And that tune is the result of countless hours of testing by riders of all skill levels, from intermediate to those who race downhill in the pro class such as Design Engineer Brandon Blakely. A Roehrig dyno was also put on the task - you can see it in action below replicating a run of Blakely's in the Cane Creek workshop.

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The Helm's Air Spring

Doublair Spring - The Helm is air-sprung, as you'd expect it to be, and Cane Creek's clever Doublair volume adjustment system allows riders to reposition a sealed piston to tune how the fork ramps up through its travel. A schrader valve at the top cap is used to set the spring rate, with an aluminum shaft running down into the positive air chamber. All standard stuff, really, but on that shaft is an air piston that's held in place with an aluminum wing nut; undoing the nut with your fingers lets you slide the piston up and down the shaft and then clamp it into one of eight different positions. Because you're effectively adjusting the air volume of the chamber, you're accomplishing the same thing as adding or removing volume spacers but without the plastic bits.


An early prototype of the adjustable volume Doublair system (left), and the aborted Triplair spring (right).


Cane Creek had been working on a second air spring system, called Triplair, that they decided against pursuing due to the added complication and setup woes that it might have caused. It was going to be offered as an aftermarket option, and it consisted of a floating air piston rather than the fixed version of Doublair, as well as a second air valve on the top cap that would have let riders pressurize the area behind it. The idea was to be able to run a lower spring rate but achieve the same sag, and it was designed to provide more support in the middle of the stroke. Setup was far more complicated, however, requiring riders to pressurize the Triplair chamber highly to fully extend the floating piston before going through the positive and negative air spring balancing procedure, and then going back to the Triplair valve (that needed an air adapter due to space constraints on the top cap) to pressurise it to be about thirty-percent higher than the positive chamber.

I rode the Triplair system at North Carolina's Beech Mountain Resort, and while it was neat to fiddle with, I had a hard time picturing many riders taking advantage of it. Factor in the positive and negative manual air equalizing (details on that below) and it all seemed a bit much to me. It looks like it did to Cane Creek, too, as they decided to focus on the simpler Doublair spring design that the Helm comes with from the factory.


The production fork's Doublair volume adjustment system - unthread the black wing nut to slide the piston up or down the air rod to adjust ramp-up, then thread the nut back down to lock it in place.


Manual Negative Air Spring - At the opposite end of the Helm's air-side fork leg is the manually adjustable negative spring. This doesn't require a shock pump, however, but rather just the push of a button. After pressurizing the positive chamber, you unscrew the aluminum cap that protects the button, and then you back out a small threaded collar that allows you to depress the valve, thereby instantly equalizing the positive and negative air chambers. You can stop at that and go for a ride, or, Morrison says, you can bleed a few PSI out of the positive air chamber to have the negative pressure be higher, which then creates an extremely low breakaway force. DVO uses their OTT (Off The Top) dial to adjust the force of their fork's negative spring for similar reasons, which is to be able to tune how the stroke feels at the top of its travel and match that feel to the spring rate that the rider requires.

You can also use the Helm's negative air spring bleed button to adjust axle-to-crown length slightly by holding it down and then compressing the fork, sort of like the trick that you could do with a Manitou fork, although Cane Creek was very clear about not recommending this as a tuning option. You can, however, use it to lower the fork if you need to squeeze the bike into the back of your vehicle or travel box.


Prototype air assemblies being assembled, and an early example of the Helm's negative air spring balance button.


The production fork's negative air spring balance button - unthread the gold collar, depress the button to equalize the positive and negative air springs, and then thread the gold collar back down.


The manual negative air spring provides additional tuning, for sure, but it's obviously more complicated and requires an extra step during setup compared to the self-adjusting negative air springs that most of Cane Creek's competitors use. So why do it? Adding tuning options aside, Morrison wanted to avoid having to use the bypass port that a self-adjusting system requires because that calls for an air seal needing to slide over a non-continuous surface, which he feels is only asking for trouble in the long-run.

Also, a bypass port means that different air legs are required for forks of different due to where the port is located, whereas going with the manual negative air spring allows Cane Creek to use the same air legs for any travel Helm, thereby making both manufacturing and purchasing easier while letting the consumer adjust their Helm anywhere between 100mm and 170mm of travel in 10mm increments via clip-on spacers. So the slightly more complicated manually adjustable negative spring does, in the end, make for a simpler product in a way.


Installing or removing 10mm spacers onto the air rod lets the fork's travel be set between 170mm and 100mm.

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Downtime and Deadlines

With a full year and plenty of time and money invested in a twin-tube damper that eventually proved to be a dead-end of sorts, and an effective but tricky three-part air spring that was left behind in favor of a simpler system, it's fair to say that the Helm's birth wasn't a walk in the park for Cane Creek. And nor should it be; it is their first suspension fork, after all. But the most challenging times for Morrison's team wasn't saying goodbye to the twin-tube system or the Triplair spring, but rather the time spent in between designing, manufacturing, and what has to be most exciting: testing what you've created.


The Helm's chassis going through some destructive testing.

The 15mm D-Loc axle is square, and the anodized black lock on the right fork leg latches it in place. Tension is adjusted via a nut under the QR lever on the opposite side.


''You get the design and you can sit there and stare at it on the computer for as long as you want, but you just need to try it. You've got to go do it, and some of the parts are pretty easy to make here; we can turn them around in a few days or a week. But some of the parts are just really challenging to make, so they take maybe ninety days before you actually get to try that thing,'' Morrison described of the evidently frustrating process.

''And, inevitably, you put it together for the first time and you immediately find something that you can make better. So then you modify it, or you have to make new parts; but, generally, you end up modifying stuff, so you end up in this nether realm where you're not where you were with the design. You're somewhere better, but all the parts are modified by hand, so you have to make another leap and say 'Okay, we're going to make all-new parts,' and you have to wait.''


Crown and steerer units cut apart during testing, and rapid prototyped compression adjustment dials.




Engineers are known for their ability to solve technical challenges, not their marketing and business skills - that's a whole other department - which sees a guy like Jim focused more on making the best possible product than meeting a looming deadline. ''It could always be better, but there's a day when you have to say, 'This is right for right now.' We're going to have to get that last two-percent next month and proceed with this right now. Right now, I think our big challenge is that we've been ninety-percent there for maybe a few months, and in the last two weeks we've gotten ninety-eight-percent there. And every time we turn around it's like, 'We just got this, and now let's do this to make it a little bit better, or let's go test this.' We're just running up against deadlines.''

Those were some of Morrison's last words to me before I left their prototyping shop during my visit to Cane Creek last spring, and those deadlines that he spoke of have long since passed. Eight months on from my visit and the Helm has been on the production line for at least a few weeks now, with the new fork already being shipped out to distributors for aftermarket sales, Cane Creek's main target at this early stage of their first fork's life.



I joined Cane Creek for a Helm test session at the Beech Mountain Resort Bike Park where we focused on air spring setup.




Cane Creek also sent me two Helms a month ago for testing and early ride impressions, which, as you can probably imagine, has been pretty interesting. One of the forks is in the dark blue special release color and the other in the black of the standard production fork, with the former left at its full 170mm of travel and tested on the front of Rocky Mountain's Slayer, while the other is set to 160mm and bolted onto Ellsworth's new Rouge.

And what do I think? Find out what I make of the Helm here. If you have questions about the new fork, post them in the comment section below and Cane Creek will get an answer for you.

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