The ‘Manto’, or mantle in English, is the middle layer of Earth’s internal structure, located between its core and outer crust, making up the majority of the total planet’s mass. In a similar way, gravel cycling represents a middle point between asphalt roads and more technical trails, allowing most routes to be covered with high performance.
In this context, Aurum has just launched their gravel bike Manto; a most anticipated release that comes after years of experience in road cycling. It brings together all their know-how into this mixed-surface discipline to provide an ‘unbound performance’ bicycle.
Just before the launch on April 28, we had the chance to take a closer look at the bikes in Velodrom, the top-notch cycling shop in Barcelona. At first glance, we saw the Aurum logo on top of the flat background color, as it is similar to the road models. The tube line and geometry look very neat and one can observe the detail put in every little aspect, from the integration of the seatstays into the vertical tube to the smooth lines and cable integration. Definitely, every detail counts and is designed to make you go comfortably fast.
What makes Manto excel
When considering the frame geometry, for both Contador and Basso (the founders of the brand), it was essential to translate the high-performance riding style from the Magma (road model) into the Manto. They revised and adjusted all dimensions to allow for wider gravel tires and off-road riding, keeping the same lively feel and snappiness characteristic from Aurum. The Manto keeps a very similar rider position as the Magma but it has a longer reach with a shorter stem. Handling-wise, they increased the front center and trail to gain stability, without decreasing the quick handling.
Power transfer is essential in high-performance riding, which is determined by the frame stiffness. To get the most out of each pedal stroke, they use an 86 mm wide bottom bracket with a similarly large downtube proportionally shaped for each frame size. The lower end of the seat tube tapers out to blend smoothly into the bottom bracket providing additional stiffness, while the thinner round upper part brings some comfort to the rider.
One can find long and thin seatstays connecting the rear wheel axle directly to the top tube. This long span of thin tubes, together with a special directional carbon layup, provides vertical compliance to the rear triangle for increased comfort over long rides. In addition, the vibration damping on the rear triangle helps to keep the tires on the ground for additional grip and control.
Using aero-proven NACA airfoils and based on the Magma, Aurum engineers designed the best cross-section profile for all tubes. Specifically, they centered their efforts on the aero-shape development for the headtube, downtube, and fork legs, as these are the primary surfaces to battle the aero drag while blending every other area of the frame smoothly.
As confessed by Aurum, achieving a low weight was an important goal for the Manto project but it was not the main focus since in gravel riding stiffness and compliance are more important. To keep this balance between weight and riding characteristics, they relied on Experience Carbon Technology (ECT). This is about using the right type and grade of carbon for each area of the frame, combined with an intricately optimized layup to avoid excess overlapping of fiber plies. This layup also varies depending on the frame size, which adds up another level of complexity and implies additional manufacturing costs. However, for Aurum it is essential to deliver the highest level of performance in all their frames.
Additional specification points
Aside from the previously mentioned features, there are other little aspects that make the Manto a very interesting bike, adapted for every rider and compatible with current industry standards.
The frame is provided in five different sizes, ranging from 48 to 58 mm. As one would expect, the withstood loads and torsional forces vary a lot from one frame to the other. Thus, the shape and dimensions for each frame have been individually designed and optimized to achieve balanced and coherent riding characteristics for riders of all heights.
Manto’s geometry has been designed and optimized for 700c wheels with tires between 40 and 45 mm wide to offer the best rolling feel and deliver a fast bike. No information on 650b tires is provided from Aurum, but given all the efforts put into the design, it would be a pity not to use the right setup.
The frame is designed for internal cable routing, directly through the stem or with a 3-hole cap for more traditional builts. Besides, the frame adopts the universal derailleur hanger (UDH) for future component compatibility and easy-to-find replacements.
Regarding customization, the T47 threaded bottom bracket accepts both 2X and 1X drivetrains, both electronic and mechanical (for mechanical only 1X). Also, the frame is delivered with frame protectors to avoid damage from the gravel paths and different cage mounts can be found in the downtube and top tube. One can choose among three different color configurations, Castilla yellow, Astur green, or Mediterráneo orange, names that represent different areas of the Iberian peninsula.