Desmosedici Stradale

For Ducati, the V4 layout at 90° is the utmost expression of sportiness for a motorcycle engine. It is no coincidence that it is the same solution used in the MotoGP Desmosedici engines.

Compared to a classic in-line four-cylinder, the lateral compactness of the V-engine allows greater centralisation of the masses and makes it possible to limit the weight on the front end of the bike. Furthermore, the shorter crankshaft generates a smaller gyroscopic effect. All these aspects have a positive impact on the bike's dynamics, helping to make it light and fast when changing directions.

The optimal integration of engine and chassis is a fundamental concept behind every Ducati project. That is why the Desmosedici Stradale was developed to be mounted rotated backwards by 42°, like the Ducati MotoGP engines, to optimise weight distribution, use more extensive radiators and to shift the swinging arm pivot forwards as much as possible.

Like all Ducati engines, on the Desmosedici Stradale the design of the Desmodromic system is a key factor for obtaining top performance. The Desmodromic system in the Desmosedici Stradale uses components that have been completely redesigned and miniaturised to obtain very compact heads, achieving a level of sophistication, compactness and lightness never seen before on a Ducati bike.

On normal motorcycles the crankshaft rotates in the same direction as the wheels. In contrast, in MotoGP the counter-rotating crankshaft rotates in the opposite direction. The Ducati engine specialists have borrowed this technical solution from the racing models for the same reasons it was applied in the competitive world. In fact, this solution has advantages related to two aspects of physics: the gyroscopic effect and inertia.

The 70° offset of the crank pins combined with the 90° V-engine layout generates a firing order that Ducati has called "Twin Pulse" because it is as if the engine were reproducing the firing sequence of a twin cylinder. The peculiarity lies in the rapid firing of the two cylinders on the left side and then on the right side of the motorcycle. In the timing diagram, the firings are situated at 0°, 90°, 290° and 380°. This particular firing order gives the V4 a sound that is quite similar to that of the Desmosedici MotoGP.

Each throttle body has two injectors: a sub-butterfly one for low-load use and another above it that comes into play when maximum engine performance is required. The throttle bodies of each cylinder bank are moved by a dedicated electric motor. Thanks to the full Ride by Wire system, this allows complex electronic control strategies and modulation of engine 'feel' according to the selected riding mode.

Magnesium occupies a prominent position among the lighter metal materials. It is not by chance that in alloy form it is widely used in competitions. The Desmosedici Stradale uses magnesium alloy for numerous components, including head covers, oil sump, generator and clutch. A technical choice that also has a positive impact on the bike's look.

The crankcases are made of aluminum using gravity die-casting and coupled with horizontal cut. The upper casing includes the four aluminum cylinder liners with nikasil coating that ensures low friction and protection against wear.

The collaboration with Ducati Corse has made it possible to achieve a compact, lightweight and high performance engine. Weighing 142.2 lb, the Desmosedici Stradale is only 4.4 lb heavier than the 1,285 cc twin-cylinder Superquadro.

Pistons having a diameter of 81 mm churn in the barrels of the cylinders, with two piston rings, low friction, plus oil scraper ring. They are moulded in aluminum and utilize the "box in box" technology that makes it possible to contain the skirt height and the thickness under the piston crown thus reducing friction and inertia loads while maintaining the required durability and stiffness.

The compression ratio is 14:1, a high value that once again reflects a design of competitive origin. The pistons are coupled to steel forged rods with a center distance of 101.8 mm.

The perfect functionality of the six-speed gearbox is enhanced by the Ducati Quick Shift EVO (DQS EVO), which offers a fundamental evolution: changing gears with the throttle open. Furthermore, DQS EVO follows different logics to shift up and down. Integration with the slipper clutch and engine brake (Engine Brake Control) ensures the system's absolute effectiveness even on the track.

The wet clutch with progressive control optimally combines high torque drive and rider comfort. In competitive riding conditions, with sudden downshifts and strong engine braking, the slipper clutch counteracts the loss of stability of the rear end, offering excellent control while braking deep in corners.

Like the MotoGP engines, the Desmosedici Stradale uses a semi-dry casing lubrication with delivery and recovery stages to ensure proper lubrication of all moving parts at all times.

The water pump, located in the V of the cylinders, is powered by a shaft driven by a cascade of gear wheels. Its location is designed to reduce the size of the circuit as much as possible, improving its efficiency and optimising engine weight.