Fact Development Process
FROM EXPERIENCE PHILOSOPHY TO FINISHED PRODUCT
It’s a universal truth. Different types of riding demand different qualities from a frame or component. That’s why, from day one, we design for those differences. We call them “experiences”.
Before development even starts, our design and engineering teams set out to fulfill a specific rider experience with each bike. Guided by the needs of that experience (e.g. XC race, Endurance Road, etc.), they determine the best combination of properties—including stiffness, compliance, strength, and weight—for each product.
With the experience as a foundation, the development of every FACT bike or piece of equipment moves through an integrated process where design, materials, and manufacturing are all chosen in careful consideration of one another. This integration of development ensures that each product is 100% built for its intended application—to give the rider exactly what they’re looking for, every ride.
Our Pro's Help Power Innovation
Saxo had specific stiffness requirements and wanted something slippery fast. Out with conventional areo tubing, in with all-new design concepts. This required radical engineering of all tube shapes.
Saxo asked for aggressive and fast. We largely designed around Fabian’s geometry and handling characteristics for the XL Shiv, then adapted the technology for other frame sizes.
Saxo’s stiffness and aerodynamic demands were only achieved through systems integration of components like the head tube, stem, brakes, BB, and crankset. Note the seamless design of stem, steerer, and front brake.
Tube-Shaped by Design
Beyond just aesthetics, the shape of a carbon frame or component has a huge impact on how it will perform. Smart tube shapes don’t just happen; they are the result of months of R&D, field testing, and years of experience riding previous models, including those of competitors.
Here are the factors we consider when optimizing tube shapes:
Strain Gauging — Allows us to determine the ratio of bending vs. stiffness in each tube and to compare the relative importance of those tubes in different stiffness scenarios.
Fea Studies — Through this computer modeling software, we can isolate different tubes for pure bending or torsion stiffness load cases or a combination of both. Full frame studies show the effect of triangulation in the front and rear triangles and the effect of a bowed top tube on compliance.
Experience — Simple. We watch how tubes deform in dynamic and static fatigue tests and make modifications based on our findings.
Tube Location — Our tube shapes are designed to resist specific forces, depending on their location. We shape the top tube differently than the down tube, for example, because each tube sees more or less loading, plus a different ratio of bending and torsion stress, depending on the riding scenario (e.g. sprinting, descending, etc.).
Frame Size — The way we see it, different frame sizes warrant different tube sizes. If we didn’t design each tube in this manner, a larger frame would have inherently lower stiffness due to the length of its tubes (meaning they flex more than a short tube under the same load). And at the same time, larger riders are capable of applying more force on their bikes. This makes determining the appropriate level of stiffness for each size bike/rider extremely important.
By designing the top tube, down tube, seat tube, and seatstays for each frame size, we can accurately and efficiently control stiffness variables from our smallest to largest frame sizes. Though size-specific tubes require much more work from the engineers who have to painstakingly design each tubeset, the result is a proportional range of bikes with consistent ride qualities across every platform (e.g. Tarmac, Roubaix, Amira, etc.).
We approach the engineering of our tube shapes and joints through a concept we like to call carbon-centric design. Carbon can be molded into just about any shape with proper engineering, but by designing tube shapes with the properties of the material in mind, we can create a much more optimized structure.
On its own, carbon fiber only possesses tensile strength. But when a flat sheet of prepreg (resin-impregnated carbon) is cured, it gains some compression strength and some bending strength. So by properly layering these prepreg sheets during the bike’s layup process and utilizing the carbon in an efficient geometric shape, we can create tubes that are capable of resisting tensile, torsion, and compressive forces, all of which we encounter while riding.
The real science lies in the ply angles of the carbon. Zero-degree carbon plies work to resist bending and +/- 45 degree angle plies resist torsion. When twisted, either the + or - 45 degree fibers are in tension (depending on the twisting direction), but when bending, one side of the tube is in tension and the other in compression. Long story short, by putting as many fibers as possible in tension (carbon is at its best when it’s in tension), we can create a stronger, stiffer bike. This is why it’s fundamental for us to know the ratio between bending and torsion in each tube.
Beyond the properties of the material itself, here are the other considerations we make in carbon-centric design:
Carbon fibers aren’t as strong when bent at extreme angles, so our engineers focus on eliminating sharp corners, creating smooth transitions, and utilizing large radii tubes.
To maximize structural properties such as strength and stiffness, our engineers use frame and tube geometry to their greatest advantage—an example being the Tarmac SL3’s large down tube and bottom bracket junction, which helps the bike achieve a superior stiffness-to-weight ratio.
We eliminate the need for extra carbon material (which other manufacturers might use to build in a margin for error to account for less-than-precise manufacturing) by making our tooling, layup, and molding processes as efficient as possible. Our hard work early on in the design process is what allows us to make frames and components of such consistent quality.
FACT Forks Go Carbon-Centric
Carbon-centric design doesn’t stop at frames; every component we create, including our FACT carbon forks, follows the same design philosophy.
Traditional fork designs use a large flat crown surface as a seat for a standard crown race—a design borrowed directly from alloy and steel forks. However, since this shape demands 90-degree changes in geometry, it diminishes the effectiveness of the carbon fibers (considering, as we said before, that carbon is strongest in tension).
In 2007, we introduced our first tapered crown/raised bearing design and put it on our Roubaix bike. The tapered section of the crown accommodates the bearing and allows the carbon fibers to flow smoothly between blade, crown, and steerer. By virtue of its geometry, tapering also provides a stiffness/strength advantage that we can prove through FEA studies. Finding this design to be widely successful, we’ve since applied it to all of our FACT full carbon forks, and now, we even use raised bearings on the majority of our carbon mountain bikes.
Fork strength and stiffness are, without question, two of the most important attributes of the bike and something we really focus on during development and testing. Strength aside, stiffness is what makes your front wheel track well when cornering and descending, so it’s paramount to the quality of your ride.
By increasing both lateral fork stiffness and steerer tube torsion stiffness, our tapered crown design creates a more confident handling bike.