When it comes to making carbon fibre frames, USA brand Felt Bicycles definitely don't hold back. In this blog post we take a trip down "technical valley" to explore the material in more detail and how Felt Bicycles create some of the very best carbon frames using TeXtreme. So sit back, grab a cuppa and enjoy!
WHAT IS CARBON FIBRE?
Once limited to applications in the aerospace industry and the pinnacle series of motor sports competition, carbon fibre has been the material of choice for high-performance bicycles, wheels, and other cycling components for several decades. Carbon fibre provides bicycle engineers with the potential to create a riding experience that offers an unmatched combination of comfort, stiffness, strength, and efficiency. With its incredibly high strength-to-weight ratio and malleability, carbon fibre is second to none for building the world’s best bicycles. In its raw form, carbon fibre is a conjoining of thin, strong fibres. These fibres come in a variety of grades based on overall strength and modulus.
The higher the modulus, the stiffer and lighter it is—in the simplest of terms, "modulus" is a term for the stiffness of a given material. However, this doesn’t mean that the best bikes are completely constructed from high-modulus carbon fibre. On the contrary, the key to building bikes is to mix and match different types of carbon fibres in order to find the ideal balance between stiffness, strength, and weight. In addition, no bicycle is crafted from carbon fibre alone—it’s used in conjunction with resin, which acts as a bonding agent to hold the structure together. It’s a complex puzzle to create a carbon fibre bike that not only rides well, but can sprint away from the competition. But just like how the finest food ingredients demand the skills of a master chef to yield a truly exquisite meal, bicycle frame materials require engineering expertise to produce a truly great bicycle.
ALL ABOUT UNIDIRECTIONAL CARBON.
Unidirectional carbon fibre is the most common type of carbon fibre used in bicycle construction. As its name implies, a sheet of unidirectional carbon has its fibres oriented in one way, or in parallel (as in, “one direction”). To help visualize the characteristics of unidirectional carbon fibre, think of a wine glass. If you drop it on a hard floor, it will shatter because it’s so thin, stiff, and brittle. Now think of a plastic cup. You can drop it and nothing happens because of its flexible properties. Carbon follows similar rules. As you increase the modulus, the stiffer and more fragile the fibres become. And if you go in the other direction, the fibres are not as stiff, but more compliant and durable. As such, there is no such thing as a bicycle frame constructed completely from high-modulus carbon fibre, at least not one that would be safe or pleasant to ride.
It would likely break apart the first time you hit a big enough pothole. High-modulus carbon fibre can be tricky to work with and there must be balance between stiffness, weight, strength, and durability. Also remember that not all unidirectional carbon fibre is created equal—there are countless varieties and versions created by various composite manufacturers around the world, each one with different weights, durabilities, vibration resistance, and other attributes that can greatly affect how a completed structure will perform. Think of different types of carbon like paper: Plain, white sheets of paper are intended for computer printers; thicker, colourful construction paper is ideal for crafts; and thick-stock, supple, and durable paper is best for archival printing and bookkeeping. Every type has its unique properties and ideal uses.
In addition to unidirectional carbon fibre, woven carbon fibre is also very commonly used in bicycle construction. As its name implies, woven carbon is composed of relatively narrow strands of unidirectional carbon fibre woven together, just as one would do with textiles on a loom. Because carbon fibre is such a uniquely versatile material, yet has inherent weaknesses when it comes to the way its threads are oriented, weaving carbon strands together gives composite experts and engineers more ways to manipulate the structure that they’re designing. But just like with unidirectional carbon fibre, not all woven carbon fibre is created equal. All have their unique properties. One of the very best types of carbon fibre that Felt have long used to elevate the performance of their bikes is TeXtreme. Read on to discover what makes TeXtreme so special.
WHAT MAKES TEXTREME SO SPECIAL?
Because Felt Bicycles was the first company in the bike industry to utilize TeXtreme in its products, many cyclists believe that it is a type of carbon created by, or unique to, Felt. However, this is not the case. TeXtreme is a type of woven carbon fibre created by the Swedish materials company, Oxeon, who make it available to dozens of brands in a wide array of industries including aerospace and motor sports. However, it’s still a rarified material in bicycle construction due to its high cost. However, pursuant to Felt's mission of giving all cyclists the best riding experience imaginable, they're okay with taking the monetary hit in order to create the very best bicycles in the world. So what makes TeXtreme ideal for use in bikes? Strength and weight.
MORE THAN MEETS THE EYE.
TeXtreme features a unique makeup that Oxeon calls "Spread Tow" technology. "Tow" is a term that refers to the specific type of thread used to weave carbon fibre sheets. TeXtreme’s Spread Tow design offers the strength of two layers of unidirectional carbon at around half the weight. Also, similarly, TeXtreme requires less resin than a comparable combination of fibres, further reducing the overall weight of the finished structure. As an added bonus, TeXtreme’s wide "checkerboard" pattern is also quite aesthetically pleasing. You can learn more about TeXtreme at Oxeon’s website.
WHAT ARE LAY-UPS & SCHEDULES?
The term "lay-up" or "lay-up schedule" refers to the overall recipe for how the various types and shapes of carbon fibre sheets are pieced together (or "laid up" in a mold before resin is added) during the bicycle frame manufacturing process. A schedule is often composed of lists, charts, diagrams, or some combination thereof, which details the various dimensions, moduli, fibre orientation, and resin content for each piece. Together, this information provides the road map that leads to a finished frame. Every bike model can contain hundreds of these entries. Many people think all carbon bicycle construction is the same. And, sure, every bike manufacturer can tweak ply orientations and materials, and use different resins to hold everything together. But if you don’t put in the time during the design phase to truly understand structural relationships, you’re just creating generic bikes.
Felt has invested heavily in its product — in its engineers, the designs, tools, and materials they come up with. I hope you've taken something away from this weeks blog post, if you want to chat more about a particular model or even test ride on just call the shop on 01179866885.