Ducati might be disappointed to be losing the now-banned winglets from its MotoGP machine in 2017 but a new patent reveals the firm has another idea that could more than make up for their loss. It’s going to turn its exhaust pipes into jet engines.
No, it’s not April fools’. Ducati’s idea is to add a clever variable-size outlet to the exhaust pipe of the Desmosedici, looking and working like the variable-area jet outlet of a fighter plane.
On fighter jets the exhaust nozzles of the engines can be varied in size by changing the angle of overlapping metal petals. The Ducati system is a miniaturised version of the same idea, using a worm gear operated by a remote electric motor via a flexible cable to alter the position of the petals.
In their open position, the exhaust will be unrestricted, much like a normal bike’s. While that’s ideal for maximum engine power, it means the gasses coming out of the exhaust are moving relatively slowly and don’t create a lot of thrust. By narrowing the exhaust aperture, the gas coming through it has to go faster and will create thrust.
While the thrust will sap outright engine power by restricting the exhaust, the idea is to use it at times when the engine’s full performance can’t be utilised. On a MotoGP bike, that’s a lot of the time – full throttle will result in wheelies or slides, leading to the traction control or wheelie control kicking in and reducing engine power anyway.
Because the thrust from the exhaust doesn’t rely on tyre grip, it can provide extra acceleration performance over and above what can be achieved with the grip of the tyre alone. And thanks to the angle of the exhaust pipes and the fact that two of the Desmosedici’s exhausts exit high up, under the seat, the thrust also works against the bike’s natural tendency to wheelie under acceleration. In that respect, the new system should at least partially replace the work that winglets have been doing in recent years.
The patent shows the system is well developed. There’s also scope for systems like these to be used on production machines. Ducati is known to be working on a replacement for the 1299 Panigale for 2018, and word is it may be a MotoGP-style V4 machine (see page 10). Since patents are only of real use to protect commercial ideas, patenting this system suggests there are plans to put it into some form of production in the future.
By Ben Purvis
