Ducati Superleggera V4 with lighter, more powerful Desmosedici Stradale R Engine

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Forum Staff
Nov 2011
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Desmosedici Stradale R Engine for the 2020 Ducati Superleggera V4




















Ducati Superleggera V4 with a lighter, more powerful Desmosedici Stradale R Engine
At the heart of the Superleggera V4 lies a 90° 998 cm3 V4 engine, lightened thanks to the use of titanium and aluminum bolts, a new, lighter 8-disc clutch, camshafts machined to reduce weight, a lighter gearshift drum, an oil pump without a return stage from the heads and titanium manifolds that work in concert with the road-legal Akrapovic silencer. These modifications have yielded a 2.8 kg weight reduction compared to the 1,103 cm3 V4 engine and produced a gain of 3 hp thanks to the high efficiency of the Akrapovic exhaust.

For those eager to ride the Superleggera V4 in its natural habitat - the racetrack - the bike comes with a complete Akrapovic titanium exhaust (not type approved for road use), included in the Racing Kit; this makes the bike 6 kg lighter than the Panigale V4 and boosts power to 234 hp at 15,500 rpm with a maximum torque of 12 kgm at 11,750 rpm.

On the Superleggera V4 Desmosedici Stradale R engine the Desmodromic system timing procedure is performed manually by an expert; once all required tests have been completed, he certifies the positive outcome by signing the metallic plate that embellishes the rear cylinder bank.

The engine is a 90° 998 cm3 V4: featuring cylinders banked 42° back from the horizontal, it has been designed to act as a fully stressed member of the vehicle. Cylinder bore is 81 mm, with the pistons performing a 48.4 mm stroke thanks to a forged steel counter-rotating crankshaft* driven by four titanium con rods with a centre-to- centre of 104.3 mm.

The crankshaft is mounted on brass bushings and combines a 70° crank pin offset with a 90-degree V engine layout. This solution generates what's called a Twin Pulse firing order, because it's as if the engine were reproducing the firing sequence of a twin-cylinder. The distinctiveness lies in the fact that the two left-hand cylinders fire closely together, as do the two right-hand ones. On the timing chart, the ignition points are, then, at 0°, 90°, 290° and 380°. This particular firing order makes the V4 sound just like the MotoGP Desmosedici.

Pistons are made of moulded aluminum, have a single compression ring plus an oil ring and take advantage of “box in box” technology: this contains both skirt height and below-chamber thickness, helping to reduce attrition and inertial loads while maintaining the necessary strength and stiffness.

The four Desmodromic system camshafts operate the valves (Ø 34 mm titanium intake valves, Ø 27.5 mm steel exhaust valves). The valves feature titanium half-cones, a solution usually adopted only on racing bikes.

The Desmosedici Stradale R engine gulps in air through oval throttle bodies and aerodynamic throttle openings (Ø 56 mm equivalent) connected to variable-height air intake horns. This solution optimizes cylinder intake across the rev range, giving major advantages in terms of power delivery and handling. The engine breathes through a high-permeability Sprintfilter P08 air filter.

On the Superleggera V4 the Desmosedici Stradale R is equipped with an STM EVO-SBK dry clutch made of machined-from-solid aluminium with a 48-tooth clutch basket and plate set; there are 8 take-up plates and 8 drive plates with a diameter of 138 mm. The dry clutch gives greatly improved 'feel' during braking and through the corners. It also allows personalization of the degree of 'mechanical' engine braking and, with the as-standard open carbon fibre clutch cover, is characterized by that iconic mechanical rumble which Ducati fans find irresistible.

Rear wheel drive is performed by a Regina ORAW2 chain - the same as the one used in MotoGP - which turns an Ergal crown; compared to those on the Panigale V4, these two components reduce weight by 1.4 kg.

* However, in racing, there's no such thing as a free lunch: this layout demands, of course, the addition of the so- called 'jackshaft' to transfer crankshaft drive through the gearbox to the rear wheel so it turns the right way. The jackshaft adds an extra transmission element to the crankshaft-wheel connection system. This needs to be taken into consideration when establishing crankshaft power if the latter is obtained from measurements made at the wheel. During both homologation and measurement on acceleration test benches it is, therefore, necessary to consider an efficiency or, in any case, an additional coefficient that is, by law, fixed at 0.98.​