Dragonfly Design Report: Frame

At Mecatecno we have designed the Dragonfly with a clear idea in mind: to bring together the capabilities of a gas-powered bike and the benefits of a green technology by building the lightest, easiest and least demanding trials motorbike we could imagine. To achieve it, we have put into practice a number of innovations, developed 100% by our engineering team. These design and innovation concepts have been developed and tested according to our idea of Electric Trial practice. We invite you to know more about it in four design report issues. This is the second one.

CFA (Combined Frame Assembly)

Main frame: ø18mm CroMoly tube
Side tie bars: CNC milled 6086 T6 Aluminium
Skid plate: 6mm 7075 T6 Aluminium
Structural motor plate: CNC milled 7075 T6 Aluminium
Anti twist skid plate clamps: 6082 T6 Aluminium

CFA is a system designed to take full advantage of the electric propulsion. This means in other words, not having to stick to the geometric rules of the gas-powered (thermic) bikes.

In general terms, a thermic bike frame has to be structural by itself. All elements are hooked to it, and it is subject to a great deal of weight, tensions and constant vibrations. As opposed, the Dragonfly frame is not structural by itself. Like the human body, in which the bones wouldn’t stay in place if they weren’t tightened by the muscles, all the surrounding elements participate structurally adding strength where it is requested. This concept, together with the fact that the number of elements is much less, quite lighter and free of vibration, allow a great deal of benefits.

• General reduction of tubular frame weight and dimensions.
• Better distribution of the suspended mass and better placement of the center of gravity that has a direct impact on stability, balance and weight sensation.
• Great control over frame rigidity with high impact strength on the central area, and controlled torsion close to the steering head that allows for a smoother riding.
• Reduction of skid plate area and dimensions that has a direct impact on the part strength.
• Simplification of assembly steps that has a direct impact on the motorbike maintenance.