Profiles for Bicycle Components by Specialized

In this article, we’ll be discussing Profiles for Bicycle Components by Specialized, WIPO publication 2019232249. The publication date is Dec. 12th 2019 and the filing date is May 30th, 2019.

Update 7/9/21: This app has finally made it to the US. 20210206449

Update 7/24/22: Still pending

Update 1/30/23: Granted

This patent was published December of 2019, but I think it’s an interesting enough patent to write about. It’s important to note that this patent is not a US patent, it’s a WIPO application. WIPO is the World Intellectual Property Organization with 193 member states. WIPO was created to ultimately resolve IP disputes across country boundaries, so it’s basically the world patent office. This patent has not been filed in the US, as far as I can tell, but it has been filed with WIPO.

Additionally, this patent is not brand new and was published about a year ago. It’s unlikely you’ll ever hear Specialized publicize this idea because it’s so abstract, but I would guarantee the designs in this patent are implemented to some bikes already in production. I wanted to write about this one because it’s interesting to see how far some of the companies will go to protect an idea.

Update 12/17/20: It’s important to note that many other manufacturers are patenting their aero frames. Orbea, Cervelo, and Trek have applied for aero bike patents. This particular Specialized patent is interesting because they’re using very specific equations to define the shape of their bike and the equations are in the claims, but don’t think Specialized are doing something nefarious here. They’ve done some serious research to determine an optimized shape and this application suggests the optimization.

After some digging, the PCT has published a Preliminary Report on Patentability on this patent. This isn’t really a ruling, more of an opinion. This opinion basically states that Specialized need to provide some more proof that this application overcomes already patented bikes.

Brief Summary (tl;dr)

Specialized are trying to patent very specific aerodynamic profiles for a road bike. They have defined desirable equations, based on an aspect ratio, that will influence metrics such a circumferences, drag coefficients, and area moment of inertias. An aspect ratio is input into the equations and the other metrics are determined. These other metrics are what Specialized believe are important enough to patent.


I used to be an aero guy in NASCAR, so this particular patent speaks to my soul. Downforce and sideforce are key components to a fast race car. Both of these metrics are difficult to improve without also increasing drag, but in the case of our NASCAR racecars, “drag is the motor guy’s problem”. That line has always stuck with me. No matter how much downforce we’d add, we would almost always take the drag hit. Our Vehicle Dynamics crew dictated this rule, as they could simulate a lap time with various aerodynamic metrics, called an aeromap. In short, they’d take nearly any amount of drag for any amount of downforce. If we could add 20lbs of downforce with 20lbs of drag, that’s a win.

In bike road racing, aerodynamics are also a key factor to speed. Ultimately, drag is king and the motor is the rider. Some teams go to incredible lengths to fine-tune the drag force of a bike. It’s no secret that Trek have used Siemens HEEDS software to optimize their road bikes. HEEDS is a software that performs automatic optimization, in this case, of a shape based on pre-defined parameters. In an example scenario of a wing, an engineer specifies a minimum and/or maximum for parameters such as chord line, angle of attack, width, etc. Effectively, a table of parameters is then created, where the table is then used to calculate and output a performance metric, such as drag, downforce, etc. HEEDS iterates the table thousands of times and spits out a graph that looks something like the graph below, where each iteration has a unique design that is accessible and usable. So, the computers are doing the designing, and the engineers are just setting parameters.

These manufacturers are using some serious technology in these bikes to improve infinitesimally small margins. It’s possible Specialized used something like this to come up with this patent.


I’ll introduce some aerodynamic metrics that Specialized use in this patent.

Aspect ratio (AR) – This one is important to remember. The aspect ratio may be calculated as the ratio of the maximum lateral width of the cross-section to the maximum longitudinal length of the cross-section. So, AR is the ratio of the width and length of a wing. In this case, the length and width of a seat tube or fork.

Circumference (U) – The circumference may be the length of the perimeter of the cross-section, which may be the arclength of the leading edge LE plus the arclength of the trailing edge TE plus twice the sum of the side.

Cd – The drag coefficient Cd may be calculated based on a free stream flow of fluid flowing in a direction parallel to the X-axis and in the -X direction as oriented in the figure.

Ixx and Iyy are sometimes referred to as 2nd moments of area, moments of inertia of plane area, or second area moment. The moments of inertia Ixx, lyy are geometrical properties of the area of the cross-section which reflects how the cross-section’s area is distributed with regard to the X-axis and Yaxis, respectively. These relate to the shape to mechanical properties of stiffness in certain directions. As the reader, you don’t really need to know this. It might be too much, but I’ll include it anyway.

Polar moment of inertia is the sum of Ixx and Iyy. You don’t really need to know this either.

Intended novelty

The intended novelty of this one is interesting. Specialized are attempting to patent equations and the aerodynamic profiles of components of a road bike determined by the equations, based on specified aspect ratios (AR). The aspect ratio is used to calculate a circumference (U), a drag coefficient (Cd), and an area moment of inertia (Ixx and Iyy).  

Specialized probably don’t want to use equations to protect the idea, but the concept and shapes are likely so complex that explaining them in actual words would be nearly impossible. Using these equations may narrow the scope of the idea.

Here are the equations, used to create an aero profile, Specialized are attempting to patent, taken straight from the claims. If you are part of Specialized or part of the law firm that wrote this patent, please go down to the ‘conclusion’ section for important notes.


‘Win on Sunday, sell on Monday’

I believe this phrase started in NASCAR. It’s a simple phrase that’s been around longer than I’ve been born and it still rings true today. Having been racing for a long time, I think the bike world has really taken hold of this idea. I’ve notice a huge uptick in Commencals after Cecile Ravanel clean up the EWS and Amaury Pierron crushed the World Cup circuit.  Hell, my wife and I both own a Commencal. The correlation between winning races and selling a product is extremely strong. It shows the product has the pedigree to win, and don’t we all want to look like winners?

“America is all about speed, hot nasty bad-ass speed”

Eleanor Roosevelt 

Specialized are in the business of winning, and business is boomin’. They’re always fast in everything discipline they enter. Whether you like them or not, no one can deny their racing prowess and their progression towards speed. Specialized are full of racers and if you were to tell them that they would have to race behind closed doors with no spectators or TV audience, I can guarantee that these guys and girls will be racing and working just as hard. I understand the obsession with the pursuit of speed and the addiction to winning and competing. It’s an awesome feeling.


This patent has some complex verbiage, so I’ll only talk about the high level points. Figure 1B shows a bike with a few cross sections C-C, D-D, E-E, and F-F.

These cross-sections correspond to each of the figures 1C-1F, where C-C is 1C, D-D is 1D, and so on.

Figure 2 shows example cross-sections that are related to the cross-sections in fig. 1B. Each profile (210, 220, etc) has an example scenario on the right side of the graph. For 210, given the desired aspect ratio of 1.55 and using the equations of this patent, the circumference (U), coefficient of drag (Cd), etc. can be determined and are shown on the right side of the chart.

Specialized state the trailing edge shape may have more adjustability:

One or more coordinates at or near the trailing edge TE may not be used in some embodiments. The shape of the trailing edge TE may be changed from the particular configurations shown and described herein and still fall within the scope of the disclosure, and thus still provide the enhanced performance characteristics, etc.

Figure 3 shows more example scenarios, but with different ranges of aspect ratios. It appears as though Specialized are saying that, given a range of aspect ratios, the circumference, Cd, etc. may be bounded by a range of values. What’s the point of the equation if you can claim a range outside the equation?

I would assume the range gives designers some leeway in the shape of the circumference of the profile, since the circumference is the only shape-influencing metric being calculated. So, for a profile with an aspect ratio of 1.5 – 4.6, U has a range of +/- 3%, Cd has a range of +/- 6%, and so on.

Specialized provide some graphs showing the relationship between aspect ratio and the other metrics. Therefore, these graphs create:

…a “family” or “library” of designs may be identified using the equations and/or plots described herein.

Specialize then show some example cartesian chart and example graph of an aero profile using these equations. These examples have a specific aspect ratio and a circumference that is calculated based on the equation in this patent.

Specialized state that these numbers are estimates:  

In some embodiments, estimates for the shown data points may be used and still fall within the scope of the disclosure. For example, FIG. 6A lists the N: =2 actual data point as (3.54, 7.63). In some embodiments, the actual data point used for N=2 may be (3.5, 7.6), or other approximations of the coordinate shown in the table.

In the end, Specialized are stating that their bikes may be designed using these equations and their performance numbers may lay on the lines in these graphs.


First off, this application appears to have some errors. Ignoring the spelling and component errors, there seems to be equation errors. But, I could be wrong here…

Second, in the claims, Iyy is defined as: Iyy=(3501.1 x AR + 2.552) mm^4 , but in figure 3 and 5D, Iyy is defined as Iyy=3501.1AR^2.552. These are completely different equations and will surely bring some rejections or issues in protecting this patent.

Third, the claimed equation for Cd does not match the results in fig 2. The equation in the claims is Cd=1.6027xAR^-1.087, which given an AR of 1.55 would give a Cd of 1.68. Given a Cd of 0.7 (like in fig 2) the equation should read Cd=(1.0627xAR)^-1.087.

Fourth, Figure 4 and the associated description makes no sense. Why are we introducing a %resid metric for a scaled component to 20mm, when in [0078] (error in the par number) states the drag and U values are based on a scaled 20mm width. What are we scaling from? There’s no indication as to how %resid is calculated, the paper just gives an example scenario and then says “%resid is XX”. If anyone in the patent industry can explain [0078-80], I am all ears.

Lastly, I do very little WIPO work, but from a US patentability perspective, there may be a reason this wasn’t filed in the US. From a USPTO paper by Molinelli:

Recently summarized in the SC [supreme court] decision in Mayo Collaborative Servs. v. Prometheus Labs, Inc., 566 U.S. 66 (2012)(Mayo), the SC has stated “Phenomena of nature, though just discovered, mental processes, and abstract intellectual concepts are not patentable, as they are the basic tools of scientific and technological work” Mayo at 71, quoting [the SC decision in] Gottschalk v. Benson, 409 U.S. 63, 67 (1972), (Benson). In a famous 2014 decision, Alice Corp. Pty. Ltd. v. CLS Bank Int’l, 573 U.S. 208 (2014) (Alice), the SC used a slightly different classification, asserting the judicial exception for “[l]aws of nature, natural phenomena, and abstract ideas,” which are “the basic tools of scientific and technological work” Alice at 216. In Alice, the Mayo “phenomena of nature” is expanded into two classes, “laws of nature” and “natural phenomena;” and, “mental processes” and “abstract intellectual concepts” are combined into “abstract ideas” indicating the definitions are not precise with bright lines. Alice at 217.

In short, the SC state that phenomena of nature are not patentable. It’s possible that this application may be considered a law of nature and cannot be owned by an individual or company.

3 thoughts

  1. Not really clear what is new here. Aerofoil libraries have existed for decades, with parameterised designs. Maybe bringing CD, Ixx and Iyy together in a couple of equations is novel? However, when the accuracy is plus minus 20%, is this really anything more than fitting curves to a set of numbers measured in the wind tunnel?

    1. The libraries of aerofoils are definitely not new. but it’s possible this very very specific set of equations are novel enough to get a patent. And yes, the accuracy/range of the equations are suspect.

  2. I’m amazed how many errors you find in patents from large companies such as Canyon and Specialized, are these normally drafted by engineers and then transcribed by attorneys?

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