At the heart of the Dash is the unique titanium and carbon fibre frame weighing only 1.3kg, the optimum material for each part of the frame to maximise benefits to the rider.
Taking an engineering-first approach to creating the Dash, along with the concept of ‘a Bike for Life’, theoretical principals were painstakingly and rigorously tested by Arial through both simulation, FEA (Finite Element Analysis) and many physical prototypes to arrive at the perfect combination.
The final result comprises a mixture of 3D printed titanium nodes, titanium tube, and carbon fibre mouldings that allow Ariel to exactly specify the characteristics for each part of the frame. The result is the very best balance of strength, responsiveness and comfort, while minimising weight in every frame member.
With learning from the Atom Ti project, with its titanium chassis, titanium was chosen as the main frame material due to its strength to weight density – the highest of any metal – coupled with compliance for a supple ride quality. The vibration damping qualities of the frame significantly reduce fatigue for the rider, particularly when compared to aluminium or full carbon frames. As with any Ariel vehicle, lightness results in an improved power-to-weight ratio, which is key to performance, handling and usability.
With no paint, lacquer, or finish of any kind required, titanium automatically forms a layer of Titanium Oxide on its surface around 4 nanometres thick (0.0000001mm) and will never rust or degrade.
The titanium nodes, where frame tubes join at the steering head, bottom bracket, seat post bracket, seat topper and rear dropouts are all made by Additive Manufacturing (3D printing) using SLM (Selective Laser Melting) from Ti-6AL-4V Grade 5 Titanium. Manufactured by RAM3D, the same process is used – on the same Renishaw machines – for printing complex combustion chamber components for space rockets and thrusters for satellites. With the internal cable runs and structural elements required for the Dash these aerospace grade, printed parts allow Ariel to manufacture components that could not be made in any other way. Internal mesh structure means wall thicknesses can be decreased to less than 1mm while maintaining the necessary strength and structural qualities for each component.
Nodes carry torque values, printed in the node, to ensure easy and correct tightening of components when working on or servicing the bike. The Ariel and Dash logos are similarly printed in the nodes. Titanium bolts and fasteners are used throughout the Dash and it is this level of detail that reflects the care that has gone into the design, engineering and build of every Dash.
The titanium nodes are welded, meticulously by hand, in an oxygen free, inert environment to Reynolds 6-4Ti Seamless ELI titanium tubing. Synonymous with bicycle frames since 1897, Reynolds association with Ariel bicycles, as well as Ariel motorcycles, goes back over 120 years during which time Reynolds tubed frames have carried 27 winners of the Tour de France.
The Grade 9 titanium tube is made by Reynolds specifically for the Dash and to lighten the tube further it is ‘butted’, meaning the wall thickness is varied through the length of each tube – thicker where stresses are higher, thinner where they are less. This seemingly small attention to detail, with wall thicknesses varying from 0.90mm to 0.75mm within a single tube can on its own deliver a 24% mass reduction in each tube.
Henry Siebert-Saunders, Managing Director of Ariel:
In our cars, we obsess about every kilogram we can save to produce the most dynamic, communicative, and exciting vehicles. But on the Dash that obsession quickly changed to saving grammes anywhere we could.
The carbon fibre seat tube and seat post allowed Ariel to ‘tune’ the parts with directional quasi-isotropic layers of material for a combination of lightness, stiffness and comfort between the seat and bottom bracket. The seat tube, which is chemically bonded to the titanium nodes, thus aids power delivery and control while saving further weight. Carbon fibre is also used for the forks, delivering an excellent combination of light weight, stiffness and vibration damping with exceptional torsional rigidity to give better steering feel and quicker turning.
This multi material approach, with a mix of cutting-edge production processes and hand craftsmanship, gave Ariel complete control over every element of the structure and produced the ultimate solution for strength, lightness, comfort, durability, performance and aesthetics. Tested to ISO4210 Standard through multiple cycles the Dash is certified for fatigue and impact as well as overall brake performance.
The frame geometry for the Dash Urban and Dash Adventure differs in a number of fundamental ways and the two models have been carefully designed with each specific use and size of person in mind. Differences in head, seat, and down tube angles as well as chain-stay lengths give the agility and responsiveness required for each model and frame size – quicker turning and agility at low speeds together with ergonomics to suit town and street use on the Dash Urban, and stability at high speed and assured responsiveness to rider inputs both on and off-road from the Dash Adventure.
All cables, hydraulic hoses and wiring are routed internally through the frame, handlebars and forks. This not only results in a unique design and very pure aesthetic, highlighting the materials used, but makes the bike easy to clean, particularly after off-road use.
Source: Ariel Motor Company
Here is the complete series of more detailed articles of the new Ariel Dash e-bike
Ariel Motor Company announces the new vehicle Ariel Dash e-bike
The frame of Ariel Dash e-bike
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