Pinarello Bolide F HR 3D 2023 the new bike of Filippo Ganna's hour record
Pinarello presented the new racing bike with which Filippo Ganna will try to break the hour record.
The new frame has been designed to minimize the frontal area, also thanks to the removal of the "3: 1 rule" by the UCI.
The wheel hubs and bottom bracket have been made narrower than normal. The bottom bracket has been reduced to 54mm (from 70mm), wheel hubs from 120mm to 89mm at the rear and from 100mm to 69mm at the front.
The next obvious improvement was to take advantage of the elimination of the "3: 1 rule".
This allows for longer and thinner airfoil sections to be used. It is well known that airfoil sections with a type ratio of 6: 1 or even 8: 1 perform significantly better than the old 3: 1 ratio.
We recently saw some bikes with very wide forks and chainstays. Do they work? The test results we have been able to gather so far are unclear. Such a system must be designed to reduce the overall aerodynamic drag of the bicycle and cyclist.
In general, in a design of this type, the bicycle will create greater aerodynamic drag but, if perfected sufficiently, it should reduce the cyclist's aerodynamic drag, generating an advantage over the aerodynamic penalty of the bicycle.
In our case, the results were too unstable and the potential gains were not large enough to adopt a project of this type.
So, we opted for the classic and proven method: narrow fork and chainstays, both close to the disc wheels. This method also creates a low weight solution and presents no unknowns in terms of production.
Metal 3D printing was first pioneered in world-class cycling by Pinarello in 2015, when the UCI timed by Tissot record-of-the-hour bike handlebar was wielded by Bradley Wiggins for a record distance.
3D printing is known for its ability to create difficult shapes with ease and to allow each unit to be tailored to a single athlete. To find the right skills, knowledge and equipment, we collaborated with Metron A.E. in the UK.
The frame and fork of the HR bike have been designed to take advantage of a new alloy called Scalmalloy, a high-strength alloy of scandium, aluminum and magnesium, an aerospace material specifically designed for 3D printing.
The choice of material and machine is fundamental.
Metron used a large format EOS M400 machine to 3D print the parts in Scalmalloy.
In fact, the frame was made up of only five pieces, with the front triangle made in three pieces and the seat stays and chain stays in two more pieces.
These pieces were made individually and, after meticulous cleaning and removal of the supports, were glued together using an aerospace-grade epoxy resin.
In addition, titanium was used on the fork crown and handlebar extensions, which are the areas of greatest stress.
A bicycle destined to be ridden by a World Champion, in addition to having exceptional aerodynamics, must also have extraordinary resistance.
For this reason, an exact copy of the frame that will be used in the UCI timed by Tissot time record attempt has been sent to the EFBE (a mechanical test laboratory) in Germany for an independent endurance test.
The frame, fork and seat post were subjected to a grueling test regime that included the full range of fatigue, impact and torsion tests as specified by ISO4210.
The result: the new Bolide F HR 3D is the first fully pedalable and UCI compliant aerodynamic bike that exceeds ISO4210 and will be ridden by a World Champion in a UCI Hour Record attempt timed by Tissot
Understanding of aerodynamics has evolved a lot in recent years. Today it is understood that we must reduce the total aerodynamic drag of the cyclist and the bicycle together, rather than focusing only on the bicycle, because, after all, there is always a cyclist on it. As mentioned, some solutions involve a potential increase in the aerodynamic drag of some parts of the bicycle, but with the aim of reducing overall drag.
The new handlebar was designed precisely to achieve this goal: After several CFD optimization cycles, a handlebar geometry was created that reduces the rider's drag more than the unconventional shape penalizes it. Overall, the aerodynamic drag is reduced. Again, 3D printing was required to produce an extraordinary shape.
In the case of the handlebar, the proven titanium (Ti6Al4V) was used on an ARCAM EBM machine. To ensure that the extraordinary shape of the extensions did not create structural problems, Metron has decided to subject them to an advanced test regime so that they can be safely driven during a UCI timed by Tissot Hour Record attempt by a powerful athlete like Filippo. Ganna.
Over the past 15 years or so, high-end bicycle designers have made significant use of modern aerodynamic research methods previously used in aerospace engineering and Formula One, especially CFD. The improvement of this technology in recent years has allowed the CFD to move from a research tool to a design tool. Cloud computing and web-based solutions now allow infinite computing power. Our simulations were performed on AeroCloud, provided by the Norwegian company NablaFlow. AeroCloud runs fully on AWS (the cloud solution of choice for many F1 teams and the FIA for their CFD simulations) and has allowed us to run multiple configurations simultaneously, providing detailed aerodynamic data for use in the design and validation phase. The simplified configuration implemented made it possible to load the models without problems and to feed the results directly into the design process, allowing us to search for the so-called marginal gains.
Some may say that this approach is not as accurate as it could be. Any researcher, moreover, is confronted with the question of accuracy with respect to the number of iterations. Experience shows that a better overall result can be achieved by running many carefully thought-out and reasonably accurate simulations rather than a few super-accurate simulations. The main reason is that doing many different iterations and analyzing the results helps engineers come up with ideas, try them out, and keep iterating.
To spot small changes, the bike and rider are broken down into individual parts and their contribution to overall drag is recorded. In reality, the secret ingredient "is the way in which these parts are added together, in which priority is established and in which one decides what the next steps should be. Pinarello and Metron have developed and perfected the method over the course of ten years of collaboration, so the improvements keep coming; we are not yet close to the “aerodynamic peak”. After the simulations, only tests in the real world can prove that the design work was successful. The Bolide F HR 3D has already proved to be the fastest bike for Dan Bigham in his personal Hour Record of 55.548km set on August 19 this year. Dan, who is a performance engineer for INEOS Grenadiers, was testing an unbranded prototype of the new Bolide F HR 3D that he had helped develop. Dan has also worked on the development of other key components that will be used on the bike, such as the crankset.The new Bolide F HR 3D can be ordered from an official Pinarello dealer starting today and, due to the 3D printing production technique, will be built only on request.