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Trellis Frame - One of MV Agusta's Cornerstones
First of all, the strength of MV Agusta has always been to be able to choose the best components on their motorcycles, without suffering the compromises dictated by cost factors. This too is an aspect of primary importance, since adopting the trellis frame is considerably more expensive than opting for a traditional beam frame.
If the latter, in most cases, is produced via casting and extrusion of aluminium, and defined by a mould in its profile and geometric characteristics, the trellis structure provides a far more complex process, almost craftsman-like, for the articulation and the type of work that it involves. To give shape to the intricate cage made of intertwining tubes you must first find the right balance between rigidity, elasticity and resistance, which means designing the pipe diameter, the thickness of the material used and the type of connections to be made between the tubes, in addition to their layout.
The nature of this structure is capable of offering numerous advantages over a more traditional frame, especially for projects that can be defined in more targeted and precise terms of rigidity, torsion and bending in every section of the frame.
One of the steps that contributes to the increase of the number of manufacturing hours and the general cost is given by the precision with which the tubes must be processed in preparation for welding to get a perfect joint. The welding operation is another significant process: in addition to maximum efficiency, since it has the function of "holding the bike together", it must also appear homogeneous, with clean lines, almost embroidered and pleasing to the eye. It must be perfectly integrated with the concept of technology embodied in the structure of MV.
The welds are made using a system called TIG (Tungsten Inert Gas), the process involves the use of a tungsten electrode under inert gas protection, which can be performed with or without filler metals. It is a purely manual welding method which produces high quality joints initially used in the aeronautical industry (during the Second World War) to replace the numerous rivets that, although of similar strength, were significantly heavier.
The advantages of a tubular trellis frame are therefore represented by a comparatively smaller structure with higher torsional resistance and unparalleled accessibility. It basically means better harnessing the horsepower of a 1000cc high performance engine, with tighter and smaller dimensions around the body of the motorcycle, as well as allowing ease of maintenance and accessibility of the hands and tools of those who must work on the motorcycle.
In all this, care should be taken in supporting one of the most common statements: "the trellis frame is more rigid than others". This is a very simplistic view and cannot be fully supported. The trellis is made with patterns of stiffness and elasticity according to the goals of the engineers that design it. In the case of the Brutale and F4, where the 4-cylinder engines deliver significant power, it is clear that it has been designed to be a solid and sturdy cage, in order to avoid negative effects under extreme use where there may be consequences such as a distinct lack of precision in braking, cornering or acceleration. However, if it were excessively rigid, there would be other repercussions...