EXCLUSIVE: Devinci Wilson Carbon - In Depth
Sep 10, 2012
Steve Smith On The Devinci Wilson Carbon
Devinci's Wilson Carbon Explained
Filmed and edited by Nic Genovese and Scott Secco
Filmed and edited by Nic Genovese
Wilson Carbon Details
• Entirely new carbon fiber front triangle
• Rear wheel travel: 216mm/8.5''
• Carbon fiber seat stay
• Split Pivot suspension
• Tapered head tube
• Replaceable ISCG-05 chain guide tabs
• Lifetime warranty (mfg. defects )
• Frame weight: 7.1lbs w/o shock (9.4 lbs w/ FOX DHX RC4 )
• Wilson SL weight: 36.11lbs
• Wilson SL 6,999$ USD
• Wilson RC 5,599$ USD
• Wilson frameset 3,399$ USD
• Availability: January 2013
Carbon Fiber Frame
The contemporary Wilson first debuted in 2011, replacing the original design with an 8.5" travel layout that employed a novel concentrically rotating axle pivot from the mind of Dave Weagle. Showing their commitment to full-fledged World Cup racing, Devinci signed Canadian racer and fan favorite Steve Smith to pilot the new bike shortly after. Fast forward to Interbike 2011, where we broke the news that the Wilson would be sporting a carbon fiber seat stay assembly, a fact that alluded to bigger projects in the works behind closed doors at Devinci. Yes, it was obvious that a carbon frame was coming, and we said as much, but Devinci was tight lipped on the subject at that point. "From the beginning of my collaboration with Devinci, we have known that at some point we would build carbon downhill bikes," Weagle explains. "Once we had experience with the seat stay assembly that showed massive gains, it was an easy decision to move to the next step and go to the carbon front triangle to see what gains we could make there."
It has taken a more than full year of development work on the Wilson Carbon to bring it to fruition, but Devinci says that the move to carbon not only delivers real benefits when it comes to ride quality, but it is also much lighter to boot. In a time when any downhill bike that comes in at over 40lbs is thought of as heavy, the complete Wilson SL tips the scales at a claimed 36.11lbs right off the showroom floor. The competitive weight is possible thanks to the frame weighing in at 9.4lbs, including its FOX DHX RC4 shock, mudguard, seat collar and drop out. No, it doesn't take the crown as the lightest frame out there, but it is respectable weight that is a pound lighter than many other options. Likely more important than its weight to many potential Wilson Carbon owners, the frame carries a lifetime warranty that speaks volumes about Devinic's confidence in its strength. It is true that many racers sell off their bikes at season's end, voiding the warranty at that point, but the fact that Devinci offers such an assurance should give riders piece of mind that the bike will be able to brush off a beating at the hands of the most aggressive riders.
Why Start With The Seat Stay?
While Devinci isn't first to the 'carbon in DH' party, they did take a different route than most other companies by producing a carbon fiber seat stay for the rear of the bike
before moving ahead with a carbon front triangle. In fact, there are multiple downhill bikes in production today that still combine a carbon front triangle with an aluminum rear end, with the manufacturer often citing both cost and design challenges when talking carbon chain or seat stays. So, why would Devinci start with the carbon swing arm that they debuted in 2011? The answer to that question lies in the Canadian company wanting to better understand the effects of using the material on a top-flight downhill bike, as well as the carbon allowing them to better tune the bike's rear end rigidity. And we're not simply talking about all-out stiffness, but rather just the right amount that won't make for either a stiff, jarring ride, or a wet noodle of a bike.
There is a point where you have too much stiffness, and so for us it was about trying to find that perfect balance point where it's not too much and too little.
- Dave Weagle
The first question that many ask about any new carbon frame concerns its weight, but there is more to the story that just how many grams have been saved compared to the aluminum version. The other part to the equation is chassis stiffness, specifically that often intangible feel that gives a bike its personality. It become clear early on that the performance difference between the original aluminum version
and the carbon model actually required different damper settings due to how the material absorbs and releases energy. At this point Devinci knew that carbon would be used for both the front and rear of the bike, but they chose to continue with the bike's aluminum chain stays due to diminishing returns when it comes to applying carbon to this section of the frame - not only would very little weight be shaved, if any, but it would also cost quite a bit more to manufacture. A bike's chain stays are also in the direct line of fire from trail debris, not to mention being under constant abuse from above and below as the chain slaps around over rough terrain.
Smooth Where It Counts
The large majority of carbon frames are created by using a bladder molding process whereby the desired shape is constructed by laying down specific sheets of carbon into a steel mold. A bladder, made from either latex or nylon, produces outward pressure to force the carbon sheets against the mold and into the desired shape. Although that may sound simple enough, there are many more steps involved before a carbon part comes to life. The technique has been used for many years with much success, but it has limitations when it comes to complex shapes and intricate sections. One of the keys to manufacturing strong and reliable carbon frames consistently is the ability to precisely apply the correct pressure from the inside, yielding uniform compaction with as few voids as possible in the carbon layup. The bladder method has a tough time being able to do just that in tight spaces, which is why Devinci has taken a different approach. They continue to use standard bladder molding technique for the larger tubes on the Wilson Carbon frame, but utilize removable silicone inserts at the head tube junction and
lower on the frame where the down tube and twin spars come together. The silicone inserts are able to get into those tight spots, areas where a bladder would have a hard time penetrating, and apply pressure to the carbon layup during the molding process. The end result is a stronger frame due to even compaction minimizing void formation during the frame's construction, an especially important fact when you consider the high-stress areas where the silicone method is employed. Cutting the frame in two for inspection reveals a smooth inner wall, and not just at the larger down or tube tube locations, but also at the both the bottom bracket and head tube junctions.
Split Pivot Suspension
While the bike is built around an entirely new carbon fiber front triangle, it utilizes the same Weagle-conceived Split Pivot rear suspension layout as found on the aluminum model. Devinci and Dave Weagle have spent years shaping the Wilson's suspension layout into a package that devours big terrain better than any other bike we've spent time on, so it comes as no surprise to us that the new bike continues with the proven design, thereby allowing Devinci to concentrate on development of the carbon front end rather than conceiving an entirely new bike from scratch. The Wilson's rear suspension consists of four major components: the carbon fiber seat stay assembly or wheel link, the Split Pivot concentric dropout pivot, the floating brake link (in the Wilson as the chain stays
), and the control link that activates the shock and handles braking reactions.
The seat stay assembly determines the rear wheel's axle path as it moves upwards from an impact, with the high main pivot making for an axle path with more reward travel than if the pivot was located lower on the frame. The design is said to allow for both excellent square edge bump absorption and pedalling efficiency, two priorities for any competitive downhill bike. At the back of the Wilson, the rear dropout pivot rotates concentrically around the axle, and the brake caliper is mounted to the bike's floating chain stays in an effort to neutralize the effect that the braking forces have on the suspension. The layout allows the rear wheel to track the ground, even when the rider is hard on the brakes.
The Control Link
While it's the concentric axle pivot receives the lion's share of attention when it comes to breaking down the bike's design, it is the nearly hidden control link (pictured at right ) that greatly determines how the bike reacts to the terrain. The one-piece unit is machined from a solid chunk of 7050 aluminum, and rotates concentrically around the bottom bracket via two massive sealed bearings. It is home to not only the two large pivot bearings, but also to both the lower shock mount and the forward attachment point of the bike's chain stays, and as such plays an integral role in the Wilson's performance. "This piece is really the heart of the stiffness of the chain stays, and also how the bike reacts to bumps", Weagle explains, with the shape of the control link determining the suspension's leverage ratio throughout its travel.
It is often assumed that a bike's chain and seat stays are the key to stiffness, and that is true to a large extent, but the Wilson's control link is also an important piece of the puzzle. But, it isn't as simple as just producing an ultra-solid piece to connect the stays to the front triangle - the goal isn't to have the stiffest rear end possible, but rather to have exactly the right amount if rigidity. This accounts for the control link's relieved shape that is far from arbitrary. "By making changes to this part we can really tailor both the stiffness and the suspension performance of the bike", says Weagle. Its location on the frame is also inline with Weagle's goal of situating the Wilson's heaviest suspension parts as low as possible on the bike.
To The Races
All of Devinci's test lab and development work culminated with Smith taking a win aboard the Wilson Carbon on its debut race at Crankworx's Canadian Open, a fast and rough course that rivals many World Cup tracks in difficulty, not to mention that he was also up against a stacked field that had the event looking more like a World Cup stop than a one-off DH race. While there's little doubt that Smith would have won aboard the aluminum Wilson, the top placing shows just how comfortable he was on the new bike despite it being built-up shortly before the event. The next stop for both Steve and the Wilson Carbon came just a week ago at Leogang, Austria, on a relatively smooth World Championship's track that couldn't have been any more different from the brutal Canadian Open course. Both the bike and Steve did Canada proud, proving both their versatility with a solid third place that was just 1.2 seconds off of the winning time.
While it is unlikely that anyone reading this will be challenging Steve on the race circuit, it is clear that the new bike is up to the task. What's more, barring the custom Devinci Global Racing paint job, Smith's Wilson Carbon is assembled around the very same as frame the production model, including the exact same geometry.
|People assume that we have prototypes with different angles and all that, but the bike you buy from Devinci is the bike I'm riding. It's the angles I like and exactly what I'm riding at the World Cups. - Steve Smith|
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