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The Heart of MV Agusta Engines: Radial Valves
The internal layout of our 4 cylinder engine is the reflection of what our racing activities, together with our research and development department, have generated over the years. A wealth of information and technological philosophy that form the basis of our engines. Among the many refined technological solutions, radial valves characterise the architecture of our in-line fours.
So what exactly is the difference between radial valves and the more traditional co-axial valves? While the latter are more popular due to a simpler layout that is well suited to the majority of engine layouts on the market, radial valves are part of a more complex and evolved project. Radial valves cannot be applied to "normal" engines but are an integral part of a bespoke project.
At MV Agusta we have chosen to pursue high standards of technological sophistication for our four cylinder engine, taking care of every last detail with precise manufacturing processes.
The heart of the engine is the cylinder head. The cylinder block and heads are designed in such a way as to centralise the valves and allow the spark plug to be placed almost exactly at the centre of the combustion chamber. The intake and exhaust valves are slightly inclined towards each other, this in itself is and advantage: it allows us to use larger diameter valves than normal. This layout creates an almost perfectly hemispheric combustion chamber that results in a superior mixture compared to traditional valve layouts. The consequences are: maximum reduction in dead spots, high compression ratio and a massive improvement in fluid dynamic behaviour. This results in a general improvement in torque and power.
A cleaner combustion chamber layout also means better engine characteristics and more harmonious power delivery. The pursuit of fluid dynamic perfection results in clear advantages especially when pushing the engine to the limit. If it were possible to gauge rider sensations when opening the throttle, you would be able to detect the extreme precision and strength with which our four cylinder engines deliver power.
Historically there have been other manufacturers that have used radial valves in their engines. Along with Ferrari for their automobiles, Norton also used radial valves in their racing engines since the 1930s, and more recently Honda used radial valves on their limited edition RVF750 race bikes. The technical sophistication and inherent rise in costs in engine development has seen a shift to more traditional, less expensive and easier to produce layouts. MV Agusta, however, has decided to pursue the ideal technological route: an expensive choice, but one that has found consensus in extreme projects such as the F4 and Brutale.