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Current Lead Times: Simple-Custom Framesets: 1 week. Full Custom Bikes: 7 weeks.

U.S. Built Custom Bicycles in Titanium and Titanium-Carbon Mix

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Titanium/Carbon Mixes – The Best of Both Worlds

laser cut titanium lugs for a 622

If you were to take a carbon fiber tube and wrap it against the wall, then hold your ear to it, there would be little if any sound emanating from the tube.  If you did the same test with metal, it would sing like a tuning fork.  The same holds true for frames, metal sings and carbon whispers.  These two qualities make for very different experiences on the road.  Carbon bikes, like our Diamas line, make pitted and potholed roads feel like you are pedaling over wall to wall carpeting; smooth, with very little feedback.  Metal bikes, like the Axiom, Resolute, Sola, and Mudhoney, on the other hand, provide constant feedback keeping you in tune with the surface of the road.  Once we start customizing and manipulating tube sets, we can alter how compliant or how stout the frames will be, but the material dictates how the road’s vibrations will be relayed to the rider.

There is a gap between whispering and singing, and to some, that’s where the perfect bike resides.  By adding carbon tubes to a titanium frame, or vice versa, we can fabricate a bike that hums, bridging the gap between the two materials.

Various carbon and titanium tubes at a desk

The idea of a titanium frame paired with carbon seat stays for the intended purpose of soaking up road vibrations was a notion that Seven pioneered and first implemented with the Odonata back in 1997, and though there have been some updates and improvements the same basic model exists today, now known as the Elium SL.

The ride of a ti/carbon bike is so pleasant, that we offer them in road, cross, and mountain bike disciplines.

The Life Cycle – Abridged Version

Long wooden crates at the garage door entrance

Every few weeks a freight truck wends its way down our steep, angled driveway to drop off two or three of these long wooden boxes. They contain raw titanium tubing in 18 foot lengths, all different gauges. The process of loading the unwieldy boxes onto a four-wheeler and moving them past the shipping department, through paint and into the machining area, one at a time, is something like a tugboat pushing a long cargo barge up the narrow, jagged length of the Mississippi River. It takes a strong sense of spatial relations and a fair amount of experience.

Wall of titanium tubing

The boxes get unpacked and the various tubes sorted by size into these vertical bays. This is our vault. This is our wine cellar. This is where the process of building a new bike begins, Matt O’Keefe standing here in front of the stock, a customer’s order in his hands, selecting the assortment of tubes that will go into their new bike.

A very long titanium tube poised to go into the lathe

We cut down the lengths to size, before butting each tube to give a very specific ride feel and handling characteristic. Then we miter the ends to fit together just so, tolerances hovering somewhere near the thickness of a human hair, the raw tubing shedding material in small increments, becoming a bike.

Titanium tubeset in a box

The modified tubes collect in small cardboard boxes, the frame builder working through a series of work cells, each with several mills or lathes in it, each set up for a very specific job, until the tubeset is complete. Then they get jigged up, so we can test the build against the frame drawing, refine any last details.

Mudhoney SL

Eventually, you get one of these. There are, as you can imagine, some important intervening steps, but this is the abridged version of the story. Suffice it to say we weld, machine, finish, polish and decal, before we get to this point. Sometimes we paint.

Barrels of titanium shavings for recycling pickup

What titanium doesn’t make it into the frame gets carefully collected in a barrel, building up over time into a strangely beautiful pile of titanium squiggles and spirals. The recycler comes by to pick these up and return them to the mill where the process starts all over, a closed loop of magic from which we extract custom bicycles.

The end..

Crafting Carbon

Diamas top tube with a filament wound 622 tube

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).