Powered By

Free XML Skins for Blogger

Powered by Blogger

Monday, 8 August 2011

Aprilia Rsv4

The engine of the RSV4 Factory is a super compact 999.6 cc 65° V-four cylinder engine designed for maximum power (180 hp). Aprilia's engine uses a Ride by Wire multimap system, a solution that Aprilia claims opens up new frontiers for engine management, with practically infinite possibilities for further development.

Besides the triple map Ride by Wire system, a sophisticated electronic injection system with two injectors and adjustable height ducts are fitted.

Aprilia RSV4 Factory has an adjustable geometry chassis allows parameters such as the position and inclination of the headstock, the height of the swingarm pin and even that of the engine to be changed.

The components are the state-of-the-art in motorcycling technology: Öhlins Racing fork, rear monoshock and steering damper, Brembo monobloc callipers, forged aluminium rims.

The needs of the optimised dynamic intake system feeding the V4 defined the strong-charactered front, with extra-large air intakes that not only develop considerable overpressure in the airbox (approx. 35 mb @ 280 km/h), but also completely separate the headlamps from the bottom of the fairing.

Smaller, lower and narrower than any 4 cylinder bike before, the RSV4 Factory's extreme compactness is its strength, together with an almost obsessive pursuit of perfect ergonomics (crucial for perfect riding control), which has always distinguished Aprilia's road going motorcycles.

Aprilia engineers have known for years that a narrow V engine layout is the ideal technical solution for obtaining a class-beating chassis architecture that emphasises the performance of the engine. Aprilia was able to draw from its extensive expertise gained in years of two-stroke racing to evaluate all possible solutions when designing a new four-stroke sportsbikes and arrived at a new 65° V-4 engine.

The narrowness of the engine allows for a very oversquare bore/stroke ratio and Aprilia claims the new engine design can rev beyond 14,000rpm. All valve covers and external housings are made from magnesium.

A unique timing system makes extremely compact heads possible (measuring only 250 mm high at the rear), especially in the area beneath the frame spars, which are thus much narrower than would otherwise be possible. The lateral timing chain drives the intake camshaft only and follows an optimised path for improved timing precision and chain durability. A gear pair at the centre of the cylinder bank transmits drive to the exhaust camshaft. This solution made it possible to obtain an extremely compact head in the exhaust area. The V4 is even more compact than the V60 Magnesium twin mounted on the RSV 1000 R. A countershaft dampens vibrations even more than in a 90° V engine. The crankcase is a monobloc configuration with integrated cylinder liners for maximum rigidity and consistent performance.
Aprilia Rsv4
Aprilia Rsv4Aprilia's RSV4 Factory engine features full Ride by Wire technology. There is no direct connection between throttle grip and the throttle valves, which are completely controlled by a latest generation Marelli control unit.

Each bank has a dedicated servo unit actuating the two relevant throttle bodies only. Hence the two banks, and subsequently the quantity of fuel injected, can be managed independently. While this solution has been tried and tested by Aprilia, it has never been applied before on such a powerful engine, thus opening up practically infinite possibilities for power delivery control. This technology immediately benefits the rider who, thanks to the triple mapping that can be controlled directly from the handlebar, can change the engine delivery mode and thus the motorcycle's temperament at any time.

Aprilia Rsv4
Aprilia Rsv4The fuel supply uses two injectors per cylinder: one injector is placed downstream of the throttle valve and a "shower" injector is placed in the airbox and starts working at high loads and revs. The technological excellence of the V4 engine is complemented by electronically controlled variable length intake ducts. At low revs and loads, the long duct favours torque and smooth power delivery. When top performance is required, the upper part of the intake duct raises, thus shortening the duct and leaving the engine free to express its full power potential. A butterfly valve in the exhaust further optimises power delivery.

Aprilia Rsv4
Aprilia Rsv4
Designed using the knowledge acquired during GP racing, the spectacular swingarm of the RSV4 Factory, like its frame, is made by combining castings (the internal part and the swingarm pin/wheel connection areas) with aluminium bent sheet elements (the external part) to form a very rigid but super light box section capable of minimising the moving masses, exalting the reactivity and sensibility of the motorcycle to the suspension adjustments. The asymmetric conformation, with an arch section on the right side and a reinforcing arch on the left, made it possible to implement an exhaust system with optimised internal volumes without penalising the rigidity of the swingarm. Here too, FEM modelling was used in the design process to optimise cross sections and thicknesses. The swingarm of the RSV4 Factory weighs only 5.1kg.

The multi-adjustable suspension, taken for granted on a motorcycle of this level, are combined with adjustments of the headstock position and rake (through interchangeable bushings), the rear end height, the swingarm pin height and - introducing a new capability exclusive to this bike - the engine position in the frame. The Aprilia RSV4 Factory is the most highly adjustable production motorcycle in the world, just like a real race bike.

Suspension
The Öhlins Racing upside-down fork has 43-mm stanchions and is titanium nitride coated to minimise friction. The wheel travel is 120 mm.

The Öhlins Racing rear shock absorber is equipped with a “Piggy Back” nitrogen canister and can be adjusted for spring preload, compression and rebound damping and length, thus allowing the height of the rear end of the bike to be changed to adjust the set-up to the different riding styles and tracks. The wheel travel is 130 mm.

No comments:

Post a Comment