This is the article: =========================================================== Having pioneered the use of winglets in MotoGP over the last few years, Ducati’s engineers will be understandably miffed to see their work go to nothing this year as that technology is banned. But far from crying into their espressos the firm’s boffins have come up with something even more ingenious. At the moment, only a lone patent document reveals any details of what might turn out to be the firm’s secret weapon when it comes to maximising performance on the track. The tech hasn’t been seen on the 2017 Desmosedici GP17 yet, but on paper the design appears to show a lot of promise. It’s an exhaust that works like a jet engine to add thrust and help minimise the loss of winglets by helping keep the front wheel on the ground during acceleration. It sounds crazy, but bear with us because the line between genius and madness is so fine as to be invisible. If it works as hoped, this idea will fall on the genius side. The system is actually quite simple. It works like the tailpipe of a fighter jet engine. If you’ve ever seen Top Gun you’ll be familiar with the way that military jet exhausts have variable geometry. An array of interlocking petals surrounding the jet pipe’s exit allows it to be widened or narrowed, altering the thrust coming out. Ducati’s patent reveals identical sets of petals, operated via electric motors, inside the exhaust tailpipes of a Desmosedici. Just as on a fighter plane, the petals allow the size of the hole in the end of the exhaust to be made larger or smaller. The idea is that when the hole is smaller, it will create more thrust. Just as you would purse your lips to blow out a candle, the smaller exhaust exit increases the speed and thrust of the gas coming out of it. There’s a downside to that, of course. Bike exhausts are usually as unrestrictive as possible to ensure they don’t sap the engine’s power. This system would definitely harm the bike’s overall output if the exhaust outlet remained small all the time. But by having a variable-sized exit, Ducati gets the best of both worlds. It makes a lot of sense. For much of the time, a GP bike simply can’t put down all of its power. Either there isn’t enough grip or the laws of physics mean it would flip over backwards if the engine was unleashed in full. In those situations, normally the only solution is to hold back the engine’s performance. The jet-style exhaust gives an alternative method of thrust, allowing a bit more fuel to be converted into forward motion. Normally, once the rear tyre is putting down as much power as it can without spinning, you’re at the limit of possible acceleration. With this system there’s an additional way to get even more forward motion without asking the tyre to work any harder. What’s more, because of the angle and position of the Desmosedici’s exhausts, the thrust tries to rotate the bike forwards around its centre of gravity. That means it’s helping to reduce the bike’s tendency to wheelie, foiling another of the physical laws that usually forms a firm limit as to the potential maximum acceleration on a bike. The downside? Presumably the bike will burn more fuel in getting this additional performance. But if it gives a race-winning edge, that’s something the team will surely be happy to live with. At the moment it’s not clear whether Ducati has tested the idea, or when it might appear on a race bike. It’s also not known whether the firm has wider plans for the concept but Ducati rarely patents technologies that it doesn’t hope to use in production at some stage. There’s a new Ducati superbike expected for 2018. A jet-assisted exhaust could be an interesting selling point to mark it out from the competition…
They would need to supply fuel to the exhaust if they intend to create thrust as in a jet engine - might as well fit a secondary jet engine to the tail unit. It won't be allowed in racing and the euro emissions wouldn't allow it either. IF it's not 'fuelled' then it's bollocks anyhoo. Was it filed on 1st April in a particular year? Did you check
Great idea. Use the gas thrust of the exhaust outlet to add in effect a few extra horsepower propelling the bike along. Presumably the left and right sides will be programmed to operate differentially to assist with cornering. Brilliant - until the whole thing gets banned. I would give it two years. Perhaps the next stage of development will be to shape and position the exhaust in such a way as to extract air from the underside of the fairing, thereby creating a bit of downforce without wings. Until that gets banned too.
apparently there is another patent for a mast, main sail and spinnaker to harvest the prevailing winds. Also a great idea proven in racing. May be a lil crazy when tacking round the hairpins and that but the idea is sound.
A MotoGP engine at full chat must produce a large volume of high pressure, high energy exhaust gas (even without an afterburner!) and it seems such a pity to waste all that energy if it can be put to good use. Like helping to propel the bike along, or reduce air resistance, or increase downforce - all of which are possibilities. More power to their elbows.
It would be a very low pressure, and is already there anyway, it would only be altered and increased slightly by the reduction of the exit aperture - this in turn reducing the engines power as said in the article. The biggest effect (although still minute) would be for the exhausts to be high level to counteract the rear tyres contact patch power delivery and subsequent vertical lift of the front wheel. Without additional fuel to create thrust I feel it would be unnoticeable.
Hang on, not yet... It is more likely to gain an advantage by exiting the hot exhausts into a low pressure area behind the bike thus reducing drag in strategic areas - common in F1 and even drag racing but maybe not looked at with bikes as yet. From a Google exhaust thrust has been experimented with and tested from way back in the days of the merlin engine. The old adage that nothing is new is often correct
