We have covered steel and titanium in recent posts. Now it’s time to talk carbon fiber.

Our approach to carbon fiber is fundamentally different than the one taken by most production bike builders, who focus primarily on the lightness and stiffness of carbon. While those are both positive characteristics of the material, we believe, in any rider-specific bike, they have to be balanced against the needs for the bike to fit properly, handle well and last a lifetime.

Though we are sometimes perceived as exclusively a Ti frame builder, we are working with carbon fiber every single day and have been for many years. We have, at this point, built thousands of custom carbon and Ti/carbon mix frames. Carbon fiber is a material we value highly for its aforementioned lightness and stiffness, but also for its natural vibration dampening characteristics. So whether we’re building an all carbon Diamas, or a mixed material machine like the 622 SLX, we always focus on why carbon belongs in the design, and then work to maximize its benefits.

There are two basic types of carbon tubing that we work with. One is round carbon tubes, like the ones we use in our Elium line, the 622 SLX and the Mudhoney PRO. These tubes are built to our specifications for diameter and wall thickness. By mixing and matching a wide array of round carbon tubes, and mating them to titanium lugs, we can tune the stiffness and handling characteristics of mixed material bikes in much the same way we do with our all Ti frames.

The other type of carbon tubing in heavy use at Seven is shaped. Just as we have an array of round carbon tubing, we also keep a significant selection of shaped tubes on hand for use in our A6 carbon line. While the outside diameter and appearance of the tubes remains constant from model to model, the wall thickness varies, altering the performance characteristics of each tube.  Cut, mitered, wrapped and bonded in house, our shaped A6 tubes give us complete customizability of fit, handling, and road feel (within the range of possibility for carbon).

Ali Engin’s photos of athletes in motion are elegant and graceful, even under the most grim and grimy circumstances.  His photo of Seven-sponsored rider Mo Bruno Roy dashing up a set of stairs against a vast blue sky, surrounded by onlookers, captured the dramatic tension of top-level cyclocross so well we decided to make a poster of it.  To us, his image says it all about the essence of racing cyclocross;  painful yet exhilarating, terrible but beautiful.

Ali’s pictures always make dramatic and dynamic use of light. Colors burst through his lense. His unique style sets him apart from many other talented photographers working at our favorite events, and we were lucky to be able to work with him on this project.

Check out more of Ali’s photos at his website:

http://www.alienginphotography.com/

A few weeks ago, Mo Bruno Roy returned her original Mudhoney PRO prototype. Affectionately called the Mo Honey PRO, that bike was the test case for the bike that became the production Mudhoney PRO, the bike that customers all over the world have ridden over the last season. Mo’s original was put together with hand cut and filed lugs, and she raced it hard this season so we could know more about our basic design assumptions, and to gather experiential data for the second iteration, Mo Pro 2.0, of this race-specific machine.

During our debrief with her, and with her mechanic/husband Matt Roy, we noted a few big, necessary changes. First, Mo wanted to change her riding position. She wanted to come forward, and up a little. To do that, she needed to make some component changes, and to maintain the handling she prefers after those changes, we needed to adjust the geometry. Easy enough.

Next, she wanted more tire clearance at the chain and seat stays. The original prototype was built with tight tolerances for racing, but we learned that just a little more mud clearance would be better. That presented a unique challenge, because Mo’s frame is small. In order to get the clearance she wanted, we experimented with a single-bend, butted seat stay designed specifically for carbon bonding. That little bit of bend gave us just what we were looking for, and it represented a step forward for the super thin stays we’ve been working with for Mo’s race bikes. The complimentary chain stays required 20 separate operations in initial machining. This is serious stuff.

In the past, we’ve built bikes for Mo that could be adapted to multiple purposes. A little attention from her pro mechanic husband would convert one of her race rigs for road training. Not this bike. Mo runs a somewhat unique crank set with 34/44 chain rings, and her seat/chain stays are optimized to work only with those rings, coupled with a 32mm tire. This is as race specific as a bike gets. It’s a bike for now, for winning races.

We opted to build for cantilever brakes, too, but only because race ready, drop bar, hydraulic disc brakes aren’t quite ready yet. Again, we wanted to build her the optimal race bike for right now, not a bike with compromises for future adaptation.

The final design hurdle we chose to address was toe overlap. Conventionally, a frame this small would have some overlap, and through the years, this was always something Mo was comfortable with, even though we offered to do away with it for her. This time out, we made some adjustments to the geometry to eliminate it, and that gives her more confidence in the technical sections of the cyclocross courses this bike was meant to destroy.

A lot of work went into pre-build design on the Mo Pro 2.0, and that led to a marathon build session that lasted long into the Friday night before Mo’s first race on it, on the Saturday. Seven Production Manager Matt O’Keefe did the final machining on this one himself, before handing it off to Staci for the rock star decal treatment.

As ever, our sponsorships are aimed at exactly this sort of collaboration. We built the original bikes to prove a concept we wanted to bring into production. After building the first generation prototypes, we then designed all the fixturing we would need to do the same design for customer bikes. In turn, the fixturing informed the accuracy and evolution of the second generation bike, which taught us about new ways to manipulate thin stays for small builds. It’s this thread that connects all our design and build work and allows everything to move forward, and to be able to pursue that thread with the input and participation of pros like Mo and Matt makes bike building fun. It reminds us why we do this.

Another solid reminder came in a Christmas tin a few days later. Her feedback on the bike itself is exactly what we wanted to hear, that it combines the best of her first Seven race bike and the first generation Mo Honey PRO. That confirms that we’re listening, and without listening you can’t build great custom bikes. It doesn’t matter whether you’re building for a pro like Mo or someone who will never race a day in their lives. The process is the same. Listen to what the rider wants. Apply everything you learn to everything new you want to do. Keep building. Keep iterating. Occasionally, just occasionally, stop to eat the cookies.

Matt made a cool time lapse video of the build that you can see here. And we were also fortunate to catch the eye of the Velo News staff at our very first race. Emily Zinn did a photo gallery of the project for their site here.

When you build prototypes you expect to see them again. As the first iteration of an idea, they are the canaries in the mine of innovation, and, if all goes well, when they return they bring back a load of valuable information with them. We now have Mo Bruno Roy’s elite race bikes back after they’ve been flogged hard on mud, grass and sand the world over. One is her Mudhoney SLX . The other is her Mudhoney PRO, known as the Mo Honey PRO when we first built it. Now we’ve done a debrief on what worked and what could have been better, and, as always, it’s time to get back to work.

Finally, some mud. Also known as the New England World Championships, the GP of Gloucester is part of “holy week” in our local cross world, and this year we had what some might call perfect cross weather, gray and drizzly and a little bit raw.

The Grand Prix of Gloucester is considered one of America’s best cyclocross races, and it was well attended by riders and racers from all of the country and the globe. For Seven Cycles this is a hometown event and our bikes could be found in nearly every race category throughout the weekend. From factory employees in the amateur categories to our sponsored professionals in the men’s and women’s UCI Elites, our Mudhoney’s were ridden hard and fast through the perfectly wet and muddy conditions featured in Gloucester this weekend.

The course was classic Gloucester; it opens with an uphill stretch of pavement through the start/finish, winds up past the beer garden steps and then dives down into muddy off-camber chicanes.  There were barriers (of course) and wide-open power sections through the grass.  Gloucester has one of the steepest and meanest loamy rocky run-ups in cross where anyone who is really running is a lot fitter than me.  There were deep mud holes and ever-changing slippery lines twisting through the trees, and day two featured a sand section that crosses the oceanfront beach at Stage Fort Park.  Spectators could watch the race and catch some amazing views of this classic New England seaport from atop a giant rock – a prominent feature in the park and a major attraction for the young ones in the crowd.

The UCI Elite women’s race featured no less than four women racing on our bikes – nearly ten percent of the field and three of them were top-ten finishers this weekend.  Mary McConneloug posted 5^th and 8^th place finishes, and Mo Bruno Roy was 11^th and 4^th.  Overall this was an outstanding weekend of racing for Seven Cycles.

- Joe W.

Our Mudhoney PRO in a custom blue, painted to match a ’72 Chrysler Baracuda

Cross season is upon us. When you have your head down, building bikes all day, you sometimes lose track of time, but then all of a sudden, you’re building Mudhoneys, and you realize, “It’s coming.” A very exciting time of year. This season we are also building the new Mudhoney PRO, for enhanced enjoyment of muddy endeavors.

Mudhoney PRO in the prototype phase

If you’ve ever been over your handlebars into a sand pit, you know that the forces that come to bear on a cyclocross bike can be both unexpected and catastrophic.  You also know that trying to get all that sand out of your mouth is much more complicated than simply swishing some post-race beer around and then spitting, like you were at the outdoor dentist.

Because of the big hits a typical CX race bike takes, we think that a pure carbon frame is the wrong tool for the job.  There simply isn’t enough forgiveness in that material to justify the weight savings you would get over a metal bike.  That doesn’t mean carbon fiber has no place on the course though.

Carbon fiber is good at two things. First, it eats high-frequency vibration better than metal, so having some carbon in your CX frame is good when you’re flying over grass or even grinding a big gear on a paved section. You’ll be smoother and get better power transfer.  The other thing carbon fiber is good at is being light.  Light can be good when you’re racing, right?

But it’s not everything.

Metal is good at some things, too.  Titanium, for example, will give a frame a suppleness and a maneuverability that an all-carbon fiber frame doesn’t have.  In the technical section of any course, in the switchbacks or in the mud, titanium will give you the ability to use your whole body to steer with.   A titanium drive train will be easier to power in chattery sections than a carbon one.  Sometimes a little flex is a good thing.

At Seven, we have the ability to build an all-carbon cyclocross racer and make it every bit as customizable as any of the other bikes we build.  When we set out to expand our cross line though, an all-carbon bike never even crossed our minds.  Instead we built the machine that would come to be known as the Mudhoney PRO.

The 2012 Mudhoney PRO

The Mudhoney PRO aspires to wring every last advantage out of the two materials in its design.  The carbon fiber top, seat, head, and down tubes form a light triangle.  Matching seat stays settle your saddle.  By putting titanium lugs and chainstays into the mix, we get suppleness where we want it, plus added durability.  A titanium drive train will improve tracking and traction; it will hold the ground better than a carbon one, especially in the more technical sections.

Marrying materials in this way isn’t easy; it takes advanced bonding techniques to gain all these advantages and still be able to offer a lifetime warranty.  Luckily, we’ve been mixing titanium and carbon since 1997.

We can’t guarantee you won’t go over the bars of the Mudhoney PRO.  When it comes right down to it, sand is unpredictable, and we could all use more practice carrying momentum from the fast parts of the course into the technical sections.  What we will say is that you won’t find a cross racer that tracks truer and holds the ground better.  And there’s always that post race beer to look forward to.

The 2012 Mudhoney PRO

We knew we could build a better cross bike, but it was a big challenge.  The Mudhoney line has served us, and the riders who race them week-in and week-out, very well.  What we know from years of experience though, is that the top step of the podium isn’t always the last step up you can take.

Cyclocross demands a lot from a bike frame.  Finding the way forward meant balancing performance against durability.  The massive torque generated by cantilever brakes made redesigning the seat stays difficult. The big impacts sustained on the fiendish obstacles race organizers throw at riders have to be absorbed somehow.  We wanted to use enough carbon to make the bike light, but to incorporate enough titanium to give proper torsional stiffness and to remain supple through the pounding of race day.

We came up with the Mudhoney PRO.

The PRO’s seat stays are titanium at the top to improve braking efficiency, but carbon at the bottom, where lightness and vibration dampening are important.  There is titanium in the drive train for maximum power transfer, and titanium in the lugs to absorb shocks.  The Ti also leaves some finesse in the frame. It’s livelier than an all carbon bike.  No other cross bike tracks so well or maintains traction quite the way the Mudhoney PRO does.  Carbon top, down and seat tubes make the Mudhoney PRO our lightest cross frame and one that shrugs off the chatter of uneven ground.

This is a race bike, pure and true.