Frame and two-member swing arm
There have been no substantial modifications to the frame used on the previous 999R, which is still of the trestle type, constructed in high strength steel tubing. The suspended engine is a bearing component and contributes to the torsional rigidity of the assembly. The cross-member supporting the starter motor on the series production bike is removable to enable use of a larger capacity fuel tank, as provided by the championship regulations. The footplates can be moved to two different positions. A great deal of attention has been paid to weight distribution and the location of each single component, which plays a fundamental role in transferring the loads experienced during dynamic riding (braking, acceleration, curves). Indeed, the individual components must be as close together as possible to contain the arms on which the masses act and as a result the momentum generated, so as to ensure highly responsive handling of the motorcycle. This is yet another reason why Ducati has followed the principle of maximum integration in designing the bike, with the aim of achieving a high density of components in a reduced volume. The swing arm is identical to that of the motorcycle which will be raced in the Superbike championships. The fulcrum support is an aluminium casting, while each arm is composed of two sheet profiles pressed and welded together to achieve a box cross-section. The left hand member also includes a lower reinforcing member. The wheel shaft is supported by two forged units welded to the ends of the arms. These components are equipped with a failure screw specified to a specific breaking strain which thus ensures that the wheelbase cannot be lengthened under stress. The wheelbase is the same as that of the 999 and the distance between the wheel centre and swing arm fulcrum is 490 mm +/- 12.5 mm (the variability is enabled by the chain tensioning slot). If the failure screw is removed and the rear wheel is set to its furthest back position, the swing arm centre distance is 512.5 mm. In this case the motorcycle's wheelbase is such as to counteract sudden variations in position during dynamic braking and acceleration (thus reducing rear wheel grip failure under braking and counteracting front wheel lift under acceleration while guaranteeing sufficient drive).
Forged aluminium alloy wheels
The rear and front wheel rims are made of forged aluminium, a technology which enables weight reduction while maintaining resistance to mechanical stress. Compared to castings, it is possible to use thinner sections since the material is distributed evenly throughout the component. The lower weight of the rims not only reduces the suspended masses (which significantly improves suspension performance), but also greatly reduces the gyroscope effect and improves the handling of the bike at high speeds (the bike is more agile when entering curves). Forging is done with a hydraulic press using special dies with a load of thousands of tons. The material thus becomes plastic while maintaining its original molecular structure and hence guaranteeing the mechanical properties of the finished part, even with greatly reduced sections. Casting, on the other hand, requires the metal to be liquid, which alters its molecular structure, and the material is poured into a mould for cooling. There is thus no certainty that the material perfectly fills all the mould cavities. To ensure that the mechanical strength of the part is adequate, castings must therefore be thicker and heavier than forged parts.
The front forks and the new rear shock absorber
The callipers of the front brakes are radially mounted to special mounts on a new -hlins fork, the legs of which are surfaced in TiN for improved sliding. The two legs have modified, smaller diameter springs and the spring guide is now in plastic rather than metal. This reduces the formation of detritus which tends to pollute the oil. The lower section of the cartridge rod is fitted with a counterspring, which counteracts the main spring at maximum extension during violent acceleration. The usual cam system allows the steering head angle to be adjusted and thus also the trail (91 - 97 mm). The rear shock absorber has been improved by making rebound damper adjustment completely independent (with a one-way valve), so that the rebound damper no longer acts on the compression damper.
Fairings: the new front fairing
The headlamp mount and the new mirror mounts are now in magnesium alloy. The fairings with scoops, front fairing between the two side fairings, the front mudguard, chain guard, silencer heat shield and windshield fairing are all in carbon fibre. The tail section, on the other hand, is in techno-polymer. The forms of the fairings are identical to those on the 999R, while the windshield fairing has changed and now lacks the upper flow guides while featuring a plexiglass windshield with a new shape. Overall, apart from improved aerodynamics, the new system provides better rider protection at high speed (when crouched over the fuel tank) and better visibility of the instrumentation (the black rubber surround of the plexiglass windshield does not block the rider's view of the instrument panel warning lights).
More sophisticated engine ECU
The new 999R's engine ECU uses the same sensors and actuators as the preceding version. However, the ECU itself has been changed to the IAW 5M2 unit, again produced by Magneti Marelli, and is now capable of handling a larger number of inputs and outputs, to allow for future expansion of the regulation strategies. The injectors (IWPR2), again from Magneti Marelli, are identical to those used on the race bike and have a higher flow rate for the same opening time. They have 12 atomisation jets and tighter, more constant flow tolerance. The form of the spray and the very small droplet size make an essential contribution to the outstanding performance of the engine. The spark plugs are surface discharge units, Champion RG59V. They do not have the traditional protruding ground electrode, so that the spark no longer follows a fixed route, but is rather generated around the central electrode in the most favourable direction. This greatly reduces the probability of misfires and hence failure of mixture combustion in the chamber. The coils are of the stick type and are therefore located in the spark plug seat on each head. The electrical connection is no longer directly mounted to the body to avoid potential damage due to vibration.
The CAN bus - a more streamlined electrical system
The use of a CAN (Controller Area Network) network with two main nodes: instrument panel and engine ECU (Magneti Marelli IAW 5M2), has greatly simplified the electrical system, with a significant weight reduction. To limit the number of cable bundles the designers have eliminated duplications in the number of sensors on the motorcycle. Their signals must therefore be shared by the various on-board processors. This can only be done by sending the sensor's signal to the closest controller, which is then charged with sending it on to the network so that it can be used by the processors which need it. The CAN bus network is composed of only two cables carrying trains of digital signals, each of which carries precise, perfectly decodable information. The nodes of the network (the instrument panel and the engine ECU), have special hardware which enables them to recognise which signal trains concern them and must therefore be processed by their processors. This technology enables a considerable simplification of the electrical system, which in some sections is composed of no more than the double CAN bus cable.
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