TECH - Design Methodology
Wind Tunnel time is critical to Felt's continued success


When we introduce a new model of bicycle, its debut comes at the end of what has been a long and rigorous development process. From initial concept to finished product, the process can, in some cases take years to complete.

The first step is a lot of dialog. Between our pro teams and athletes, our engineers and product designers, there is never a shortage of ideas (and opinions). It is a big round table process guided by what we want to achieve as an end result. Before turning on an engineer’s workstation, we zone in on the cycling discipline, goal and ultimate objective. Then the real work begins.

Our engineers design every frame and fork from the ground up using sophisticated CAD software called Pro-Engineer as well as Solidworks. This software allows them to specify every dimension of every tube, as well as the shape of each. Components such as derailleurs, wheels, and brakes can be fitted to the 3-D model to check all fit and function before a single sample is made. The engineers determine the handling geometry as well as the dimensions for each size frame. This is where a bicycle’s character begins to take shape. At this stage, the engineers start to plan for aerodynamics and stiffness through tube shape and wall thickness. For our full-suspension designs, this is the point at which the linkage is designed and wheel path is determined. This is the phase in which we developed some of our most iconic designs, including Equilink™ and the Bayonet™ Steering System.

In designs where aerodynamics is a factor, the 3-D solid model is imported in computational fluid dynamic (CFD) software called Star CCM+. CFD is like having a virtual wind tunnel in a workstation. Tube profiles can be reshaped and refined dozens of times before any sort of prototype is made in order to maximize the bicycle’s efficiency against the wind. By the time we enter the wind tunnel with a prototype, the design has been through hundreds of hours of analysis. If we’ve done our homework, what we learn there is that the design is ready to proceed. Nonetheless, it does present another opportunity to refine the design a bit further. This is when we take an actual physical prototype model to the wind tunnel and test the design. The prototype is tested, and we can make small tweaks to finalize the design. This is done before the molds are cut. So we use the wind tunnel for development as well as validation.

This process is uniquely different from what most other companies do. It has become fashionable for many bicycle manufacturers to market the fact that their bikes might be wind tunnel tested. The truth is, anybody can book wind tunnel time and test their bicycle. The difference is, Felts are wind tunnel developed.

The final phase of our development is where a first mold is cut and carbon fiber prototypes are made, or in the case of aluminum frames, they are welded. With carbon we will experiment with different lay-up configurations as well as different blends of material. To these samples we perform static load and stiffness tests in the lab to gauge the strength-to-weight and stiffness; our own internal strength standards are higher than even the most stringent U.S. and European governmental regulations require. We inspect these prototypes closely for manufacturing tolerances, surface finish and alignment among other details. Finally, we ride the prototypes to make sure they deliver the ride quality we are seeking. It was in riding prototypes that we hit on our signature UHC blend of carbon fibers.

Each model has a different design cycle based on its use. Full-suspension and aerodynamic models will spend a great deal of time in development before a first prototype is made, while carbon fiber road bikes and hard tails will go to prototyping much sooner, but stay in that phase much longer. Getting the blend of materials just right to find that lively feel while maintaining strength, stiffness and low weight can require riding many prototypes.

The stamp of approval comes when we get a thumbs-up from our teams and athletes. If it works for the very best in the world and they approve of it (and ultimately win on it), we are comfortable bringing it to market.

By taking a flexible development approach based on the needs of each bicycle, rather than applying the same approach to each bicycle, we are able to focus our efforts on the most critical elements of each model. There are other ways to develop a bicycle, methods that are faster, cheaper and less expensive. They don’t interest us. Our method takes longer but it results in a better bicycle. We’re here because we want to make the best bicycle possible.