Just about every new high-end bike wheelset to hit the market these days is made of carbon fibre, with the wonder material now being used not only in the rims, but for hubs and spokes as well. These new wheels from Dart, however, rely on a completely different, all-natural, composite known as BioFiber, promising environmental benefits and "F1 grade" performance. Is this the future of composites in the bike industry?
Carbon fibre has plenty of envious properties, from its high stiffness-to-weight ratio to the fact that it can be cured into obscure and complex wind-cheating shapes. It's little surprise then that for the last few decades nearly all of the best road bike wheels have been made of the stuff.
That is up until now and the release of the Dart (Dynamic Advanced Research & Technology) four-spoke 'BioFiber' composite wheels. These new kids on the block claim to be "ideal for speed freaks seeking to lower their carbon footprint through the use of innovation."
How is this possible? Well, Dart says it has used what it calls BioFiber, an all-natural composite and the latest high-end technology as used by McLaren Racing in F1 (shown on the right below). Diving a bit deeper it would appear that it's flax fibre being used, although this isn't stated on the company website.
"Gerard LeCain, Cofounder of Dart Advanced, explains: "Flax fibre is the basis for the BioFiber wheels, but DART doesn’t use one particular product (although all are top-end F1/Aerospace sourced materials).
"DART wheels have been designed to use multifibre technology – one single company doesn’t supply all of these fibre technologies to us. Therefore, it takes three suppliers and five source products to create the materials for the composite part of our BioFiber wheels.
"That’s part of the reason why we name them our own product (BioFiber) – because our suppliers do not provide to us a finished product. It goes from one company to another for further processing before it comes to us for layup."
All of that happens right here in the UK (see we do still make things here!) and DART uses its own moulds, not open moulds. The 'Airblade 4' wheel system is designed to comply with ISO 5775-2 and ISO 4210-7 standards, meaning that it can be used for competing in triathlon and UCI events that don't involve a mass start. For UCI mass start events, wheels must have at least 12 spokes.
Naturally, there are quite a few wheels in the range to suit different conditions and riders. Dart says that although the designs look similar, each wheelset has a use-specific BioFiber layup and monocoque.
The Airforce range (available in 60mm and 80mm depths) is said to be optimised for TTs and triathlons, the Strikeforce wheels for road use and the Groundforce is for all-road, dust trail and cobbles.
All of the wheels come with a 10-year manufacturing defect warranty. Dart clearly has faith in the strength of its BioFiber rims as the original owner is entitled to 65% off RRP if they get damaged within the first three years.
The Airblade 4 series wheelsets are tubeless straight-side (TSS), hookless wheelsets and have a claimed weight of 1,680g (in the 60mm Airforce version with machined billet hubs). Dart has also collaborated with CeramicSpeed, and each wheelset features no less than six custom-sized handmade bearings for 'pro-level' performance.
Internal and external widths vary on purpose from 21mm internal and 25mm external for the TT version, up to 25mm internal and 30mm external for gravel. The wheels are currently available with Shimano freehubs, with plans to stock Sram XDR soon.
The hubs are presently 7075-T6 and 6061-T6 machined from solid billet, and made specifically shy of aerospace standards with an intended tolerance of between +/-0.02mm or +/-0.5mm. There are future plans for a 3D-printed titanium option.
So, is all this actually any better for the environment than using carbon fibre? Dart says: "There is no carbon fibre in our BioFiber wheels. Our composites feature high-performance engineered variants of differing modulus and different variants of fibre.
"We use CO2-neutral BioFiber for dampening and structural reinforcement, and our entire advanced monocoques have a far lower CO2 footprint than wheels made from carbon fibre, and without CF dust pollutants being dispersed into the atmosphere.
"Our all-natural fibres reduce our carbon footprint dramatically because they absorb CO2 in their natural development stages before they are engineered into high-performance materials and wheels."
As with many new technologies, it comes at a cost. The Dart wheels start (yep, start) at £3,499.99 per pair, which makes them a similar price to the most expensive carbon wheelsets on the market such as the Zipp 454 NSWs.
Dart says it is currently working on a range of BioFiber rims that can be built up on ‘off the peg’ hubsets as well as its own, meaning more people could benefit from the environmental benefits of BioFiber as they will then be suitable for mass start or UCI-regulated races. Dart anticipates these wheels will be its first mainstream seller, will retail for around £2,000 and weigh ~1,450g per pair.
LeCain adds: "Basically, the whole concept of DART is to adopt a McLaren-like level offering and concentrate on products that encapsulate sustainability virtues – natural fibres, aluminium and titanium all offer that in droves.
"Additionally, DART products will focus on being beautifully designed and engineered to top-level standards using the absolute highest quality and latest technology materials and will continue to be derived from the F1/Motorsport, and aerospace sectors."
Dart wheels are available to pre-order now with the first wheelsets expected to ship at the start of 2023.
As the world becomes more environmentally conscious and consumers demand lower-carbon products, it seems very likely that we'll see more brands switching from carbon fibre to natural fibre alternatives.
Will a component's environmental impact be influencing your next purchase? Let us know in the comments section below...
Jamie has been riding bikes since a tender age but really caught the bug for racing and reviewing whilst studying towards a master's in Mechanical engineering at Swansea University. Having graduated, he decided he really quite liked working with bikes and is now a full-time addition to the road.cc team. When not writing about tech news or working on the Youtube channel, you can still find him racing local crits trying to cling on to his cat 2 licence...and missing every break going...