O.M.F.G! It’s Aprillia’s new RSV4
Posted by nicolascallegari on July 2, 2009
Check out the original story on Wheels 24 here: http://tinyurl.com/ngn7ds
Aprilia’s RSV4 Factory, claimed to be the world’s most advanced superbike, has finally arrived in South Africa and it’s clear designer Sergio Robbiano has kept his 2006 promise that “everything else will be old after the RS4”.
The Aprilia RSV4 is the only V4-engined superbike in production, and it’s already proved to be competitive against the best that Japan, Italy and Germany can serve up at the highest level of superbike racing. Max Biaggi is fifth in the world superbike riders’ championship halfway through the RSV4’s first season of competition, and Aprilia lies at a comfortable fourth in the manufacturers’ championship.
According to Aprilia the RS4 is as close as you will ever get to the real WSB deal. The adjustable geometry chassis allows parameters such as the position and inclination of the steering head, and the height of the rear swingarm pivot to be adjusted. The positioning of the engine in the frame can also be altered to change handling characteristics to suit rider preferences and different circuits.
The Factory version that’s just arrived has Öhlins Racing front forks, with their 43mm stanchions titanium nitride coated to minimise friction. As in Biaggi’s and Shinya Nakano’s race bikes, the forks allow precision adjustment of pre load and compression and rebound damping.
Looking after the rear end is an Öhlins Racing shock absorber that can be adjusted for pre load, compression and rebound damping, and length, allowing ride height to be optimised to suit rider preferences.
Brakes up front are some of the finest radial calipers, Brembo monoblocks, mated to 320mm diameter stainless steel floating discs developed by Aprilia especially for this machine. A Brembo “Serie Oro” system utilising a 220mm stainless disc and dual piston caliper with a racing type pump and integrated reservoir slows down the rear wheel.
Naturally it was a challenge for Aprilia to develop a brand new four-cylinder engine – their first – which would be capable of delivering the performance the chassis deserves. The Italian engineers’ creation is said to be superb, though, and Max Biaggi proved it at Monza in May by establishing a new World Superbike top speed record of 326km/h.
“The super compact 65 degree V4 combines the factory’s mechanical engineering know-how, gained in winning well over 300 World Championship races, with state of the art electronics, to produce a truly significant engine for the 21st Century,” says Aprilia.
The bike utilises full ride-by-wire technology with no mechanical link between the twist-grip and the throttle valves, which are controlled by the latest generation Marelli control unit.
Each cylinder bank has a dedicated servo unit, actuating the relevant throttle bodies only, allowing the processor to manage the fuelling for each cylinder independently. Three engine mapping programmes are available, controlled from the handlebars, allowing the rider to change the power delivery mode to suit prevailing conditions.
By using a 65 degree V-angle layout rather than the 60 degree of their V-twins, Aprilia was able to build the engine very over-square, with the resulting large bores allowing for very big valves and high revs. The bike allegedly revs happily to 14 200 r/min and produces its peak power of 132kW at 12 500 r/min, with the torque peak of 115Nm arriving a little earlier, at 10 000 r/min.
To keep control the weight of the RS4 as tightly as possible, Aprilia’s engineers made use of ultralight materials for the engine, with all valve covers and external housings being made from magnesium. The frame, at just 10.1kg, weighs virtually the same as that of the twin-cylinder RSV, while the trick aluminium swing arm weighs just 5.1kg.
The Aprilia RS4 Factory is the closest you are likely to ever get to the WSB version, but at R245 995 this privilege doesn’t exactly come cheap.
To ease the blow Aprilia will throw in a 24-month unlimited distance warranty.
Technical specification
Engine: V-4 cylinder, 4-stroke
Displacement: 999.6cc
Bore x Stroke: 78 x 52.3mm
Max torque: 115Nm at 10 000r/min
Max power: 132.4kW at 12 500r/min
Dry weight: 179kg
