In tandem: how additive manufacturing and bicycle production have come together

There’s an unmistakeable cycling trend in the 3D printing industry, with companies across the additive spectrum demonstrating their capabilities by printing functional bicycle components. Most recently, composite AM specialist Arevo complemented the announcement of a new CEO by unveiling a 3D printed bicycle made from carbon fiber composites.

It’s not just 3D printing companies, either: cycling companies are increasingly turning to AM for producing and even redesigning critical bicycle parts. Famously, British pros Chris Froome and Geraint Thomas used 3D printed cockpits made by Italian bike manufacturer Pinarello in the opening stage of last year’s Tour de France. Just last week even, Froome was spotted riding a bike equipped with a plastic 3D printed chain keeper.

But what is it exactly that has drawn the AM sector to cycling and vice versa? Clearly, there are elements on both sides that have led to innovation in the emerging 3D printed bicycle category. Let’s take a look.

Unchaining design

One of 3D printing’s biggest overall benefits—design freedom—is in large part responsible for its draw to cycling manufacturers. Long tethered to traditional manufacturing processes, bicycle manufacturers have relied on tried and true production and design methods for decades. The advent of 3D printing and other digital manufacturing processes—as well as the emergence of new materials—has opened the doors for redesigning and reengineering, and has breathed new life into the bike manufacturing sector.

With the ability to easily prototype and test new designs for bike frames, handlebars and accessories, manufacturers such as Pinarello, Australia’s Bastion Cycles, Empire Cycles and others are exploring new design possibilities for bikes. These new possibilities partly come from AM’s ability to produce complex internal and external structures—such as lattices—to create parts with optimized strength and functionality.

Prova Cycles, a small Australian company specializing in bespoke, hand-built bicycles, made headlines recently for its 3D printed stainless steel bike components, a driveside chainstay yoke and a non-driveside dropout. The stainless steel parts, designed to have thin outer walls and a mostly hollow lattice interior, showcase incredible strength while reducing the weight of the bike.

A bicycle AM timeline (click on the year to see highlights)

Racing ahead with lighter materials

While steel has historically been the go-to material for bike production, in recent decades lighter materials such as titanium, carbon fiber and, to a lesser extent, aluminum have become increasingly sought after. Having a lightweight bike offers a range of benefits to a cyclist. For one, it enables riders to go much faster and climb more easily. Second, it makes the bike easier to transport and carry. And third, lighter bikes can be easier to handle and are more responsive, which is especially appealing for competitive cyclists.

Carbon fiber and titanium have emerged as two of the best materials for cycling because of their lightness, strength and vibration absorption. Titanium and titanium alloys stand out for their incredible durability (compared to carbon fiber which risks damage under certain strains). When combined with AM and CAD design, titanium has proven to be a remarkably versatile material, useful for not only racing bikes but also more rugged mountain bikes.

Working in collaboration with UK bike manufacturer Empire Cycles in 2014, metal AM specialist Renishaw demonstrated the ability to produce a 3D printed bike frame from a titanium alloy that offered a higher density than its aluminum counterpart and a 33% reduction in weight. This impressive weight reduction was achieved by integrating a mostly hollow, optimally structured interior into the titanium frame, which would have been impossible using traditional manufacturing methods. This example, which gained huge media attention, was a one-off (largely because of the high cost of producing the bike), though Empire Cycles has made clear its interest in pursuing additive technologies for bike manufacturing.

As Empire Cycles writes on its website: “The design freedom afforded by additive manufacturing is immense and inspiring. A bit daunting in fact. Continual improvements can be made easily. Rapid iterations can be made. There’s flexibility to make design improvements right up to production. And as the component cost is based on volume and not complexity, some complex shapes and ultra-light yet super-strong parts are possible at minimal costs.”

Bespoke spokes

Perhaps the most important advantage that 3D printing offers bike manufacturers is the ability to produce bespoke components. For racing cyclists especially, having a bike frame and handlebars optimally built for your body and movements can be critical in giving you that tiny edge you might need to win the race.

Of course, custom, handmade bicycles are already established in the cycling world, but 3D printing adds new possibilities into the mix. For instance, the technology enables custom parts to be designed and produced faster than custom bikes made using CNC machining or molding.

MOST, Pinarello’s in-house component brand, turned to additive manufacturing to produce custom titanium handlebars for British cyclists Chris Froome and Geraint Thomas for last year’s Tour de France. Pinarello, which has been manufacturing bikes since 1952, said 3D printing was used to lower production costs and lead times for the bike parts which were designed based on the computational fluid dynamics of each rider and finite element analysis. These high-profile handlebars were made using a powder bed AM technology, and even bore the unmistakable rough finish of 3D printed titanium.

The AM cycle

For additive manufacturing companies, producing a 3D printed bicycle—even as a functional prototype—has provided a suitable and accessible way to demonstrate their technology’s commercial viability. In other words, 3D printing a functional bicycle frame from titanium or carbon fiber which integrates complex internal geometries and load-bearing capabilities is an effective way to showcase a 3D printer’s potentials for a range of industries.

Silicon Valley company Arevo emphasized this when it recently unveiled a $300 carbon fiber bike frame printed using its innovative robotic AM system. “We can print as big as you want,” commented Arevo CEO Jim Miller. The company, which is in talks with bicycle manufacturers, is also hoping its demonstration will draw the interest of aerospace companies.

Similarly, 3D printing service Sculpteo demonstrated its digital manufacturing services by designing, manufacturing and ultimately riding a bicycle made almost entirely (70%) of 3D printed or laser cut parts. “It serves as a proof of concept of what can be easily achieved with our services, and our wide range of materials,” the company wrote on its blog.

In early 2017, Sculpteo designers Alexandre d’Orsetti and Piotr Widelka began a 1,000 km cycle ride from Las Vegas to San Francisco on the 3D printed bikes. Along the journey, Sculpteo further demonstrated its services by providing 3D printed replacement parts along the way. Spoiler alert: the journey was a success!

Pulling ahead

Admittedly, there are some limitations to implementing 3D printing technologies for bicycle production. The biggest one—cost—explains why 3D printed bikes are still rather niche and are geared mostly towards aficionados and pros.  After all, not every casual cyclist needs a custom-built bike worth thousands or tens of thousands.

However, advances are being made on that front. As Arevo demonstrated, it was able to produce an entire bicycle frame using its composite 3D printing material for just $300—a cost it says is comparable to production costs in Asia for a similar product. This feat could be an indication that affordable mass customization for bicycles (even commuter bikes) could be on the horizon.

Ultimately though—and not unlike other AM-adopting industries—it seems that as additive manufacturing automation improves and hardware and material costs are driven down, implementation will increase. In other words, while only a handful of specialized bike manufacturers are working regularly with 3D printing, exploring its benefits within the bike-making craft, it will be interesting to see how the technology is increasingly adopted and applied as AM itself becomes more mainstream.