Bicycle design requires an immense amount of analysis and we were very impressed by the level of research and the detailed report of how each component of the bike had been improved.
The Cervélo Rca introduces aerodynamics to the world's lightest bicycle frame while maintaining class-leading stiffness. Using their Concurrent Aero & Structural Engineering (CASE) approach, engineers and designers worked together in a cross-disciplinary process to maximize the structural and aerodynamic performance of the final design. Utilizing in-house F1-level engineering design tools - (CAD, FEA, CFD), Cervélo was able to virtually test all aspects of frame performance. The Rca also features the cycling-world debut of new technologies such as 3M™ PowerLux™ Composite, which allows reduced weight for equal strength, and Integran/PowerMetal Nanovate™, enabling a safe, secure yet very lightweight fork.2. The Brief: Summarize the problem you set out to solve. What was the context for the project, and what was the challenge posed to you?
With such technical and sporting success seen by the Rca's predecessor, the R5ca which was the world's lightest and stiffest bicycles frame and was ridden to victory at the 2012 Giro d'Italia, the mission for the new RCA was clear: Improve on it. First of all, make it even lighter. Second, keep the optimum stiffness. And third, add as much aero as possible. Long known as the team focused on driving technical advances aimed at making riders faster, Team Garmin-Sharp riders requested a light, stiff bike that was also aero. Their request and our mission matched perfectly: (1) Make it lighter. (2) Keep the stiffness. (3) Add aero. To successfully meet these requirements called for all our engineering capabilities.3. The Intent: What point of view did you bring to the project, and were there additional criteria that you added to the brief?
In order to begin engineering the RCA, we systematically quantified the performance effects of every parameter of the frame. Knowing how each parameter affects the weight, stiffness, comfort, and aerodynamics of the bike gives us the control needed to tune the various parameters to achieve an optimum blend of all the performance attributes. This parametric analysis is the engineering preparation necessary before beginning design of the next Cervélo. It’s doing our homework. Of course, the effects of many frame parameters are already well known, such as oversized frame tube dimensions increasing stiffness. Basic tube cross section dimensions strongly affect frame performance (weight, stiffness, comfort, aero). That’s why existing Cervélos have Squoval or TrueAero tube shapes; relentless engineering towards either light weight or aerodynamics naturally results in those distinctive families of cross sections. But other frame dimensional parameters, such as depth of the chainstay crotch or lateral spacing of the seat stays, also have an effect. What happens to frame performance if you choose a larger radius between the seat tube and down tube? Smaller? If you choose a longer down tube chord, or shorter? What happens to overall frame stiffness if you take material from the chainstays and put it in the seat stays? In order to maximize performance and minimize weight, we quantified the effects of those parameters and more.4. The Process: Describe the rigor that informed your project. (Research, ethnography, subject matter experts, materials exploration, technology, iteration, testing, etc., as applicable.) What stakeholder interests did you consider? (Audience, business, organization, labor, manufacturing, distribution, etc., as applicable)
Having our own advanced composite R&D lab in the heart of the U.S. military-industrial-aerospace region makes engineering the lightest and stiffest bikes easier for us. Project California functionally allows us to have full control: Our aerospace engineers, our composite analysis tools, our CNC cutting table, our tool design and mould fabrication, our moulds, our test lab, all under one roof. The fact that every Rca will be completely cut, kitted, laid up, machined and bonded by hand, in this same lab, makes it possible for our engineers to push the performance limits farther than ever before. Project California has already excelled in raising the light weight and stiff bar in the R5ca, and this same technology has already trickled down into every R-series Cervélo made today. As the designated sole manufacturing site of the new Rca, Project California is a foundational component in the creation of the new Rca. Laminate Tools lets our engineers predict structural properties & behavior of complex anisotropic materials. This stress-based analytical layup development process results in the right carbon, in the right spot, giving optimal performance with no excess weight. One key to quickly optimizing the lay up is software that can accurately predict direction and magnitude of stresses and strains throughout a complex multi-layer, multi-geometry composite structure. Simple FEA isn’t enough: we’ve added Laminate Tools to our engineering capabilities to enable ply-by-ply analysis, modeling each of over 400 pieces of carbon fibre individually, including their individual dimensions, location, orientation and varying material properties. As you reduce weight by taking out carbon, you have to be sure the carbon left behind to do the work is in the right place, in the right orientation, in the right amount and of the right type to withstand the demands of the job. Other bike companies might farm out this analysis step to outside consultants for their most expensive model only, or use the “make it and break it” technique of physically testing moulded prototypes, but neither of those techniques provides the engineering precision or insight of being able to see analytical results directly, nor the in-depth technical insights necessary to successfully trickle to successfully integrate the increased performance throughout our model line. Having our own advanced F1-level CFD simulation and analysis capabilities in our Toronto headquarters makes engineering the most aero bikes easier. Our software, our aerodynamicists, our CAD models, our visualization tools, all painstakingly validated and calibrated to our wind tunnel test results, make it possible for our engineers to push the aero performance limits farther than ever before. Another necessary element to engineering the new Rca is our industry-leading wind tunnel test protocol. We use only the best wind tunnels, fully qualified and aerospace-certified to provide minimal blockage, minimal boundary layer thickness, uniform velocity and flow conditions throughout the test section, and a long expansion section behind, to let the wake form naturally without affecting upstream flow or pressure forces that can create unrealistic flow conditions, which can corrupt the drag measurements.5. The Value: How does your project earn its keep in the world? What is its value? What is its impact? (Social, educational, economic, paradigm-shifting, sustainable, environmental, cultural, gladdening, etc.)
The Cervélo Rca has virtually no economic value for Cervélo. In fact, even though each of the limited run of 325 frames will sell for $10,000, the project will still lose money. The value of the Rca is two-fold: both as an example of a process and as an example of a product. The process, utilizing CASE (Concurrent Aerodynamic and Structural Engineering) and virtual testing of 93 iterative frame designs, creates and new paradigm for how bicycle frames can be designed. And the product, a bicycle frame that weighs less than a full water bottle yet is stiff enough for the world's best racers, while at the same time giving riders an aerodynamic advantage, creates a new paradigm for bicycles themselves.