BikeRadar was recently offered the opportunity to take an in-depth look at British Cycling’s radical track bike used at this summer’s Olympic Games, the Hope HB.T Paris.
An evolution of the original Hope/Lotus HB.T that British athletes used at the 2020 Olympic Games, the changes compared to that bike are relatively minimal at a glance.
The HB.T Paris still uses the same wide-stance fork and seatstays that shook the cycling world to its core when they were revealed in October 2019, for example.
Nothing in elite sport can ever stand still, though, and when British Cycling announced the updated model in July 2023, there were plenty of new, unexplained details that set the pulses of tech nerds racing.
The fork, for example, had been redesigned with a sawtooth profile on its leading edge, while the cockpit had been smoothed and refined.
Out back, there was also a striking, 3D-printed split seatpost (among other existing 3D-printed parts) made by Renishaw, an additive manufacturing specialist with a factory near Cardiff, South Wales.
As part of a factory visit involving two of Team GB’s gold medal-winning riders, Emma Finucane and Sophie Capewell, we were offered the opportunity to get up close and personal with the Hope HB.T Paris.
We also had the opportunity to quiz Capewell on the bike’s performance and talk to Ben Collins, a lead additive manufacturing application engineer at Renishaw, about how 3D printing is influencing cycling at the highest level, and when everyday riders might start to see it make a meaningful impact on their bikes and rides.
No standing still
The bike we saw in Cardiff was in a pursuit setup, meaning it had a set of bullhorn base handlebars and aero extensions in place of a more traditional drop handlebar.
The wheels are round and the frame’s front triangle is a familiar mix of aerofoil-shaped carbon fibre tubes. However, the rest of the Hope HB.T Paris diverges significantly from conventional wisdom.
Both the fork and seatstays are radically wide, to disrupt the airflow over the rider’s legs at the front of the bike, and then to hide in the rider’s wake at the rear. The idea is the bike is faster overall with a rider present than without.
After all, as expensive as these bikes are (according to the UCI’s Final Equipment List for the 2024 Games, the Hope HB.T Paris – which comprises the frame, fork, seatpost, stem and handlebar – costs a whopping €29,188), they still can’t ride themselves.
As previously noted, the trailing edge of the fork legs now features a sawtooth profile.
British Cycling is coy on the exact function of these, but we can practically guarantee they serve an aerodynamic function – perhaps turbulating the airflow before it hits the rider’s legs, for example, thus increasing the effectiveness of the fork’s wide-stance design.
Although its implementation is different, it appears similar in concept to the bumpy seat tube on Filippo Ganna’s 3D-printed Hour Record bike.
The bike we saw was a frame-size XXL1, and takes 'long and low' bike geometry to a whole new level, with an enormous 516mm of reach and only 486mm of stack height.
To put that in context, a modern road racing bike such as Giant’s TCR Advanced Pro features only 412mm of reach and 596mm of stack in its largest size (XL).
Ever more AM
The fork legs and seatstays on the HB.T Paris are joined to the frame using 3D-printed junctions, designed – surprise, surprise – to be as strong, light and aerodynamic as possible.
These junctions have also been updated on the HB.T Paris compared to the original bike.
The seatstay junction, for example, now features a larger 3D-printed section, while the interface between the fork legs, handlebar and head tube has been significantly refined.
Notably, while the 3D-printed rear dropouts remain, the fork dropouts now appear to be moulded directly into the carbon blades.
Up-front, the aero extensions and the integrated risers have also been updated, with deeper, more ergonomically shaped aerofoils used. This can help to reduce any gaps between the rider's forearms and the extension, potentially reducing drag.
As before, these are 3D-printed and each set of extensions made for Team GB is customised to suit the proportions and bike fits of individual riders in the squad.
Perhaps the most striking new component on the bike is the 3D-printed split seatpost.
In the flesh, the design is even more impressive, with the upper aerofoil section tapering to a knife-like thickness on the trailing edge.
According to Renishaw, the backwards-leaning shape and gaping hole allow “airflow through the centre of the bike”.
It appears similar in concept to Trek’s IsoFlow – the kite-shaped hole in the seat tube that first appeared on the seventh-generation Madone in 2023.
Trek says IsoFlow helps to accelerate the airflow through the hole, leading to a reduction in the size of the trailing low-pressure wake that follows a rider and bike pushing through the air.
Dr Oliver Caddy, lead project engineer at British Cycling, says that while constructing a part such as this using “traditional methods” and materials such as carbon fibre was possible, additive manufacturing enabled British Cycling to customise the seatposts and cranksets to each individual rider, in a time-effective manner.
This was especially important given the shorter than usual turnaround time between the delayed Tokyo Olympic Games in 2021 and Paris 2024.
A sprinter’s dream cranks
While the 3D-printed cranks don’t appear all that different from standard carbon ones at a glance, Capewell immediately singled them out as “the best cranks I’ve ever used” when asked whether she and the other Team GB riders could notice a difference when given new, supposedly better pieces of kit to use.
For most riders, after all, a crankset is a crankset – even brands that love to talk about tiny differences in performance between different components don’t spend much time talking about crankset stiffness.
As an Olympic gold medal-winning sprinter, though (Capewell, Finucane and their teammate, Katy Marchant won gold in the women’s team sprint at Paris 2024, breaking the world record on the way), these are clearly things that matter.
Capewell also said she felt the 3D-printed integrated drop handlebar (which is made by Lotus, along with the fork) was tangibly stiffer than a standard, non-integrated setup – especially when using a long stem to achieve a stretched-out, aerodynamic riding position.
This, she said, helps make the bike handle better and feel more “direct” when putting out big efforts.
To this point, Collins said Renishaw’s cranks are among the lightest and most aerodynamic available, yet can withstand 350kg of force on each arm, thanks to their complex internal lattice structure.
To optimise this, Collins says Renishaw uses “topology optimisation software” to increase the thickness of the internal lattice and strengthen stress points, while reducing it elsewhere to save weight.
The spindle is also massively oversized compared to the 24 or 30mm spindles typically used on road and mountain bike cranksets.
Olympic tech for everyday riders?
Asked when – if ever – this kind of tech might make its way to the kinds of bikes everyday riders can afford, Collins pointed out that, to an extent, it’s already happening.
3D-printed saddles are increasingly prevalent, for example, while mainstream brands such as Pinarello are using additive manufacturing for both high-end, special-edition bikes (such as Ganna’s Hour Record bike) and smaller parts such as saddle clamps for its Dogma F road bike.
Likewise, Atherton Bikes is building trail bikes, such as its latest A.150.1, which use 3D-printed titanium lugs (made in Renishaw machines) paired with carbon tubes.
At the moment, though, it’s fair to say this technology is almost exclusively reserved for high-end bikes and parts, produced by relatively small brands.
For a technology such as 3D printing to go mainstream, it needs backing from bigger brands – both inside and outside of cycling – to help bring costs down.
In cycling, large brands such as Giant and Shimano are heavily invested in other manufacturing technologies such as carbon fibre and forged aluminium (respectively). If either was to begin producing 3D-printed bikes or parts on a large scale, the cost of retooling would be significant.
Collins says “entry-level” additive manufacturing machines from Renishaw, which feature a build volume (the space within which it can produce things) of 250x250x350mm, currently cost around £350,000 to £400,000, but its “most productive” machines can cost around £700,000.
And it’s worth remembering the cost of the machines doesn’t account for the cost of materials (such as titanium, aluminium, plastic or other composites) needed to produce things with them.
Beyond machines and materials, though, Collins says there’s also the cost of re-skilling staff in new design and production techniques to consider.
And if the potential performance gains aren’t enormous compared to producing parts using existing techniques, then many brands may not view the increased costs as worthwhile.
After all, national federations might be willing to invest hundreds of thousands of pounds or dollars per rider on bikes for the Olympics, but it's not something most riders can or want to do (although, if you do, the Hope HB.T Paris and other Olympic track bikes are technically supposed to be for sale to the general public nowadays as per the governing body’s regulations – albeit you’re unlikely to find them in your local bike shop).
Despite these challenges, though, Collins sees the increasing adoption of additive manufacturing in large industries such as medical, aerospace and consumer electronics as something that should help bring the “cost per part” of 3D-printed things down in time.
It’s worth remembering carbon fibre was once a super-expensive wonder material, but even the best cheap road bikes will typically come with a carbon fork these days.
So, while your next bike might not be 3D-printed, perhaps the one you buy in 10 or 20 years could be.
Specs | Team GB Hope HB.T Paris
- Frameset: Hope HB.T Paris
- Drivetrain: Renishaw 3D-printed alloy crankset with carbon fibre chainring
- Wheelset: Hope tri-spoke and track disc, tubular
- Tyres: Vittoria Pista speed, tubular
- Handlebar: Lotus 3D-printed
- Seatpost: Renishaw 3D-printed
- Saddle: Pro Stealth
- Weight: Unknown
