Giacomo Guidotti, Crew Chief for Hector Barbera with Avintia Blusens, explains the intricacies of the pneumatic valve engine which the team have recently started using.
Ducati has been using desmodromic valve drive for many years. The system uses a second cam to close the valve. There is a spring, but it's an anemic thing that can only hold the valve shut, not haul from full open to closed at ~18000+ RPM.
There are companies that have actually developed quite sophisticated 2-stroke technology, but it doesn't make headlines. Evinrude has been advertising for a long time having 2-strokes that can run for miles with no oil without locking up, low emissions, high torque and a number of benefits over their 4 cycle engines.
Direct fuel injection, this is the reason why Evinrude achieved that results. It requires fuel pressure at 200/300 bars, and ( in car engines ) create a lot of unburn deposit in the combustion chamber. There's always a trade-off.
I wish car manufacturers did this. I'm talking about regular cars and not supercars only few can afford. This technology would be amazing to tune with ! No camshaft, no camshaft chain/belt, and the ability to control each valve at any time for any duration would be a dream for tuning.
Dont make the mistake of assuming these bikes have no camshafts. Its only that, due to the high rpm nature of their engines, they cant rely on the valve springs to return to their original position in time. Basically pneumatic "spring" is faster than regular metal spring so that valves properly follow the camshaft profile and dont knock on the pistons.
That is the reason of manufacturers participation in moto gp to purify the product, I'm an old timer and can remember in the late seventies aluminum frame tech being so hot that teams were sneaking into their competition pits and removing scraping of aluminum from gp bikes to analyze it's construction of alloys.
Freevalve would be better as air is basically a spring where as an electronic coil doesn't have any of those difficulties. Plus, you need and air tank big enough. Where as a coil doesn't need any of those difficulties.
On the best day under the best conditions Max 200hp! Thats the last model competing with the 990 4 strokes, which had around 230hp back in the day!! Micks last bike had 190 hp top's!!!
computer controlled bikes are here to stay. they're more reliable and can be more controlled. Yamaha actually uses a gps system to control the engine tune to what part of the circuit the bike is at.
@Nick this was a long time ago. I assumed back then they were using it for fuel tables and ignition timing. Not traction control. That seems stupid and dangerous. The gps cant tell if the tire is slipping. Are you sure thats how the system works?
@Nickno worries. Im not at all arguing ir getting frustrated. I am enjoying learning from you as well. I know the bike itself has a gyro. Thats how it knows if the back is sliding. And wheel speed sensors to know if its spinning. From my understanding the GPS just tells the ecu hey at this time, switch to this programmed map. And because theres lag in a gps signal, the engineers have to program in that factor of delay. I dont really know how they do it. But thats my guess. Because when you use a gps in your car or on your bike the speed reading isnt instant. I have an R1 so a lot of this stuff is on my bike minus the gps stuff of course. I know its nowhere as good as theirs. But it is pretty amazing and seems to work well. Ive been at heavy lean and open the throttle coming out of corners and it pulls like a monster with no tire slip. Way more acceleration than i was ever confident enough to apply without traction control
+michaelovitch They actually do around 16,000rpm max. But 1000cc valvetrain parts will be bigger (=heavier). Pneumatic valves also open and close quicker so more air can get into the engine.
+michaelovitch The pneumatic valves free up horsepower. That's their main advantage... Valve float is not hard to control with heavier valve springs, stronger valve seats and valves. But the heavier springs rob horsepower, hence why pneumatic is the best solution. This video is not very good at explaining anything. If I didn't know how to build race engines, this video would sound Chinese to me.
+ZeroBoostBuick Thank you for your answer. I knew it's a system used on F1 cars,but it seemed quite useless for me since springs are used on 600 cc at this rpm. I've been told by Richard reistje and it makes sense ,that here,the valves are heavier,so stiffer are the springs. So ,yes,they certainly gain by removing this effort on the engine. i don't know if they gain on reliability and weight however.
Sorry Mr blue, Motogp banned GPS mapping 3 years ago and all the factory bikes had it. But ridiculously it is still allowed and used in the full factory WSB bikes as is electronic suspension banned from GP, that will change very shortly.
Manufacturers need to follow change to 2 strokes.Neither racers or us need 4strokes. They need to to look how evinrude and yamaha make marine direct injected 2strokes that pass the toughest emissions standards and have 4stroke consumption.
This announcer in the beginning has no idea what he's talking about. @0:15 he says "Hector Barbera replaced regular valve springs with pneumatic valve springs". WHAT! there is no such thing as pneumatic valve springs, the air pressure replaces the springs. That's the whole point of the pneumatic valves.
As 46 might say, "Fhaaaak! That music, it is not so good." (Dorna, you don't need to make every freaking video MTV-ready.) The Repsol bikes can reach 17K as needed. If, as Giacomo says, the Avintia bikes are spinning only 15,500, I'm not clear how much air springs will help. If nothing else, they'll allow more aggressive cam profiles, which will probably help fuel consumption as much as power, as well as add RPM headroom for future engine updates.
My figure was taken from the statistics show on the bike in the Honda museum in Japan. Quite simply it said 230 -236 bhp. My eyes don't lie. Technically the modern bikes may be better, but who wants to ride a bike that is controlled by computers. I would bet my life if you ask any of the current MotoGP riders they would prefer not to have computers controlling every other thing. Bring riding back to the riders I say.
Mohd Sifat This is the highest level racing, there are no drawbacks when it comes to performance. It's expensive but that is no drawback to a world championship race team, it needs more maintenance but again that's no drawback to a race team, higher revs means a little more engine wear, but again no big deal to a world level race team... These bikes are worth between £400,000 to £600,000 and the actual motogp bikes (not CRT) are worth 2 - 3million£ (the customer version of the Honda is 1.7 million Euros) they have huge budgets. :)
2 stroke have reeds or disk/rotory valves, they are still valves.. but I would like to see someone add reeds to a 4 stroke engine, of course it would have to be a brand new design,
Yes :D There is just no good reason to use 4 strokes in racing (unnecessary weight and less power). On the streets it's a different thing (beyond 300cc).
Ducati does use desmodromic valve in their MotoGP bikes. www.cycleworld.com/2014/04/25/cw-tech-valve-control-history-and-why-ducati-is-committed-to-desmodromics
Ducati used to use desmodromic technology on their Engine for MotoGP using mechanical force from the camshafts, the camshafts have dual lobes for each valve, one to open and the other is to shut the valve... Mercedes used them at one point in their F1 engines also.
some of you are comparing a 2 stroke to a 4 stroke but that's apples to oranges. a 2 stroke will always make more power than a 4 stroke because it makes it's power every stroke of the piston not every other stroke.
Ducati motogp engine 100% similar to Ducati's production bikes. In fact, Ducati is the only bike makers that had the balls to bring their street bikes to motogp. Japanese bikes have zero relevance to their road going bikes, with the exception of Yamaha which only shares the cross plane crank.
This is 2 complicated and expensive to maintain, the decuir engine technologies springless valve train(similar to desmo valve) is a better option =inrBHHVVfng. if all the crt are allowed to rev at least 17k with this valve system MAYBE their gap with prototypes will reduced
Marek Sumguy Not so. Current technology allows for full electromagnetic control of the valves. No valve spring, no camshaft, no tumblers, no fancy mechanics to compensate for valve calibration. Entire movement of the valve is electronically controlled by the computer. For practical purposes a valve should here be understood as identical to a hefty loudspeaker conus and can thus be driven with a powerful (but straightforward) audio amplifier. 6000 rpm = 100 Hz which is 50 actuations per second in a 4 stroke engine. This is mere subwoofer territory for audiophiles. This also allows for all sorts of "wacky" valve travel. Like during start: keep intake valves closed and exhaust valves minutely opened until oil pressure has been detected, this to reduce load on the starter due to the compression stroke. Or during low rpm and high turbo boost open intake valve just before exhaust valve is closed in order to vent exhaust gases out of the cylinder. Or during high rpm and closed throttle, delay exhaust valve opening in order to aid with "engine breaking". Or during low turbo pressure open exhaust valve at 80% of the power stroke in order to aid in spooling the turbo up. etc., etc.. In short: EVERY piston stroke can be individually adapted to suit the power demands of the vehicle. How fokking awesome that would be. Between you and me, I suspect Audi is doing this with their LeMans diesels. Since Audi behaves rather paranoid about showing the innards of those diesels. And their diesels seem to behave noticeably different from "regular" diesels.
Man, if it was that simple they would have done it already. And you ALWAYS need some kind of valve spring... or it would consume way too much power to use electromagnetism for valve-acceleration AND deceleration at higher rpm. And how do you keep the valve closed if not by spring pressure?. Testing has already been done with electronic valves. And they were found to be less efficient than regular cammed valve actuation/control.
it opens and closes the intake and exhaust valves using air pressure and computer control instead of mechanical systems such as shafts, rockers, springs, rods... The advantage is that they can keep the valves open/closed for longer and they can also change on the fly how long to keep them open/close. Its pretty cool. You can also do that electronically, (Freevalve tech by Koeinigsegg)
@@Crazylalalalala Its just an air spring not an actuating system and is just a piston in a cylinder which compresses the the air every time the valve opens. Not rocket science.
@@Davidkxf I stand corrected. I was way over thinking it. Look like you are correct, and I was wrong. it is just a spring replacement. That can keep up with a high rpm engine unlike a steel spring. Thank you
