The Streetfighter V4 mounts the 1103 cc Desmosedici Stradale: the 90° V4 (rotated backwards by 42°) with MotoGP-derived Desmodromic timing, unique in terms of its counter-rotating crankshaft and “Twin Pulse” firing order. 

For Ducati, the 90° V4 is the ultimate expression of sports attitude for a motorcycle engine. It is no coincidence then that MotoGP Desmosedici engines adopt the same solution. 

The 90° V layout of the cylinders allows for a natural balancing of first order forces, with no need for a countershaft – with an increase in weight and power absorption - to eliminate vibration. A very important benefit in terms of the reliability and mechanical efficiency of an engine that reaches engine speeds in excess of 14,000 rpm.

The Desmosedici Stradale is designed around the Desmodromic system, essential in terms of performance. The four camshafts move the sixteen steel valves, the intake valves measuring 34 mm in diameter and the exhaust valves measuring 27.5 mm, impressive values if related to the 81 mm bore. The valve seats are made of sintered steel. Considering the high engine speeds of the V4 and the significant size of the valves, these would not be able to follow the aggressive cam closing profiles if a spring system were used. This is why the Desmodromic system is indispensable.

As on the MotoGP prototypes, the crankshaft is counter-rotating, which means it rotates in the opposite direction to the wheels, to compensate for the gyroscopic effect and ensure handling and agility in the changes of direction, as well as reducing the tendency to wheelie during acceleration and braking. 

Crank pins offset by 70° combined with the 90° V layout of the engine result in a firing order that Ducati calls “Twin Pulse”, because it is as if the engine were reproducing the firing sequence of a twin. 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 at 0°, 90°, 290° and 380°. This particular firing order makes the V4 sound very similar to the MotoGP Desmosedici.

As for maximum power, the new camshafts have higher lift (+ 0.75 mm for the intake cam and + 0.45 mm for the exhaust cam) and are also lighter thanks to larger lightening holes and narrower toothed drive wheels. The lengths of the variable-height intake ducts have been modified to match intake to the new lifts; the long-duct configuration is increased by 5 mm, while the short-duct configuration is reduced by 10 mm.

The cooling system has been redesigned to guarantee consistent performance even in very high temperatures or during extreme use on track. The effective cooling area of the water radiator has been increased by 17%, while the oil radiator benefits from a more efficient, race-derived water circulation layout that is dual flow. 

With respect to the Panigale V4, the final drive has been shortened - 15/42 vs 16/41 – to ensure more torque at the wheel and an immediate throttle response.

For the first time, the Streetfighter V4 uses throttle bodies with variable length funnels, the same as the Panigale V4. These contribute to boosting power and ensure a prompt response.