Ducati, the 1098 and WSBK rules

[Punjistick]

Wiki had this to say: "In a conventional engine valve springs close the valves, and the camshaft (directly or indirectly) opens them. This system is satisfactory for traditional mass-produced engines that do not rev highly.[1] Steels used for valve springs were a major engine performance limitation until vacuum melt processes to extract impurities from the steel were developed in the 1950s. Even so, in the 1950s, valve springs often would fatigue and break after extended operation above 8000 rpm. The desmodromic system was devised to enable sustained high rpm operation."

[joeswamp]

That wiki entry confirms what I remember from engineering school 20 years ago: that desmo valvetrains were a cool idea in the 1950's, not so much today because of improved valve spring alloys and we now understand the system better. 50 years ago lots of folks used these systems in high revving race engines, but now nobody does except for Ducati. You've gotta figure that if the desmo system provided a significant advantage then everyone in big $$ racing (MotoGP and F1) would be using it. F1 I believe is now using pneumatically actuated valvetrains.

So my guess is that Ducati uses desmo systems because that is their philosophy.

Here's a good summary of valvetrain design issues:

Four-stroke cycle engine valves - Wikipedia, the free encyclopedia

[Karaya One]

You are now seeing F1 style pneumatics for valve operation being considered.

[Tabby]

Having the Desmo setup allows much more aggressive valve opening and closing rates than springs supposedly allow. It is still a valid design, but in motogp, it is now competing with pneumatic springs, which apparently have none of the metal springs weakness. In production I4s, there isn't as much of a need for a Desmo system, as the current valve trains are stable at the piston speeds the I4s run at. The biggest generalized reason is because the valves of a four only have to open roughly half the distance.

[Doc]

You've gotta figure that if the desmo system provided a significant advantage then everyone in big $$ racing (MotoGP and F1) would be using it. F1 I believe is now using pneumatically actuated valvetrains.

So my guess is that Ducati uses desmo systems because that is their philosophy.

I believe Desmo valves are patented so no one can use them.

[Tabby]

Ducati was not the first to use a Desmo system. In the 30s or 40s, not sure here, Mercedes had a desmo setup in one of their formula cars. Apparently you could spin the whole valvetrain with your fingers, when the head was on a bench. Way cool! There may have been others as well. Ducati just popularized its' use, and indeed, put it to good use. I don't think there is a patent. Maybe on Ducatis actual mechanism.

[highsider]

Are these the same valves that require constant, expensive maintenance? What a great idea....

I think Degsy once told me that no Ducati has ever finished some bigshot endurance race because of those stupid valves. What a stellar idea. They make less power, but hey - they're expensive and they break a lot!

[Tabby]

Without any bias, every design has tradeoffs. I guess it is what you are willing to accept. Me, I'm lazy. Give me a no-hassle valve train. If it does the job with minimal fuss from me, I like it.

[akira700]

Desmo engine makes less power?

At least in Moto GP the Duc is the power king.
Watch race one ? Stoner was making the others look
downright silly down the straight ! Never was the power difference
so obvious.

This is all getting confused as we initially started talking about
the WSBK effort... its obvious Ducati can make a decent
non-V-Twin engine. Why dont they use that tech to spill
over into their Superbike efforts? Most of the $$ is in the development.
That part is already done. I say Desmotronic engines for the masses !

[joeswamp]

I believe Desmo valves are patented so no one can use them.

Patents don't prevent others from using the design, just means they have to negotiate a fee (which they would if the advantages were so clear cut). In any case the concept of a springless valvetrain is so old that only the details of Ducati's latest designs would still be protected. As somebody else mentioned, Mercedes was really into desmodromic valvetrains in their 1950's race engines -- my understanding is that they were the biggest pioneers of this kinda setup. I believe Alfa and Jaguar might have had them briefly as well.

[Tabby]

Desmo engine makes less power?

At least in Moto GP the Duc is the power king.
Watch race one ? Stoner was making the others look
downright silly down the straight ! Never was the power difference
so obvious.

This is all getting confused as we initially started talking about
the WSBK effort... its obvious Ducati can make a decent
non-V-Twin engine. Why dont they use that tech to spill
over into their Superbike efforts? Most of the $$ is in the development.
That part is already done. I say Desmotronic engines for the masses !

Also, with the 800, Ducati went back to an even firing order, or "screamer" design. "Big Bang" or passive traction control engines, if you will, will no longer be needed, as electronic traction control constantly evolves. So the reasons for a twin in Superbike, are to me, sticking to stubborn tradition, purely for the sake of being different. There was an old cliche. Ducatis are the thinking man's Harley.

[TLRMan]

You are now seeing F1 style pneumatics for valve operation being considered.

Suzuki is doing it now on their GP bike....

My bad about Honda running a V5....Oooops!

[benVFR]

Yah the Suzuki has been pneumatic for a year or two now. The 990 had it at the very least last year to prepare for the 800s.

I've seen a couple pictures pointing out how "tall" the airbox is on the Suzuki with a note that it's cause the pneumatics take up more space then usual.

But this is totally pointless.. as others have said nothing on the Ducati street twins seems to have any need for Desmo valvetrains... do any of the street Ducatis rev any higher then an RC-51 or TL? The only thing it seems to be good for is sound & dealership service margins.

This whole "win by changing the rules" thing is ruining lots of kinds of racing. Any innovation and new groundbreaking engineering just gets you penalized to balance the field. It seems to be an issue in auto racing too. It's not the way I like to see things going. Where is the motivation to try something crazy and new that could bring huge benefits to all bikes?

Ducati has the V-4 in MotoGP, they had actually almost brought a V-4 to market MANY years ago (before Honda), the company is not going to tank if they abandon the V-twin for superbike.

[a13x]

Hey check out that forest.

All I see is trees!

[Doc]

Ducati Valves are very easy to adjust, My tune ups cost the same as a comparable 4 cylinder.
The new Ducatis service fees are not any higher than the new 1000's

I read that somewhere.

[benVFR]

Yes but you're getting them done at least 2x as often if you're following the schedule.

The 1098 has a longer adjustment interval @ 7,500miles, but Honda and Yamaha are now up to 16,000 miles. Not sure about Kawasaki and Suzuki but I bet they're at least 12,000 miles.

[Rye]

Did everyone fail to read the part about the Japanese, all four of them, making the same stink about their 750's not being competitive and lobbied to race 1000cc I4's or they would depart?

Do none of you even look at the LRRS rulebook, like Ultralight Superbike, and see that different types of bikes having different allowances is completely NORMAL?

I like the part about Ducati needing to 'make better twins' and their engineers are asleep on the job. Hello.. Desmo valves anyone?

I'm glad these decisions aren't left up to Message Board Experts.

You talk about 'seeing the forest through the trees', the big 4's complained because the f'n cheat Ducati's were running 916's! Better yet, as a real Ducati enthusiast...you would have known they were running 996's in their 916's! By my calc, that is a nearly 250 cc (33%) advantage over their counterparts! They've got chassis advantages in addition to their valve actuation advantage. But I know you're doing your part as a representative of the man now...just don't tell me you can justify a 33% bigger motor. That is embarrassing.
Also, If you saw the most recent round @ Valencia, you would see how closely matched the 999 was against the I4's. Xaus was passing at will in corners on that tight circuit.

[Awesome]

Both sides have legitamate points. I'd much rather see ducati making a competative bike within the rules. I'd love to see an inline four or a V four or whatever with improved technology. I don't think stock charts tell us anything pertaining to superbike racing. We all know that WSB and AMA bikes are nowhere near stock bikes. Apples n' oranges seems to be the popular saying around here.

On the approach side, i think building the bike and THEN lobbying for the rule change is not the propper path, either is 'give us what we want or we walk'. I don't see KTM, Aprilla, Augusta and buell saying bend the rules for us so whatever we build can compete. And the statistic of 90% wins for ducati? So they have great riders, and well run racing teams? There are lots of top level riders on other teams too. Last I heard Biaggi, Corser, Haga, Barros, and Vermeulen were pretty good riders too.

If ducati wants to stick to their 'philosophy' of NOT changing then that's their business. i don't see why the associations should have to conform to their requests though. Harley has a philosphy too that they've stuck to for a long time. That's why they're not on the racetrack anymore.

As far as the side debate. I can tear down and rebuild a honda in 6 hours tops and i've done it a number of times. I however could not change the front sprocket on Nazo's Ducati. Everything that bike needs he goes to the dealership and he pays out the ass. Everything his racebike needs he comes to me. With some free oil and a few beers.

[Rye]

the company is not going to tank if they abandon the V-twin for superbike.

I disagree. The WSBK class exists so people can watch "their bike" run circles around a track. The v-twin is as much a part of the Ducati's as it is with a Harley. They would never maintain a GP and WSBK experimental platform. I don't think any mfg. would...see Suzuki with the TLR.

[Doc]

You talk about 'seeing the forest through the trees', the big 4's complained because the f'n cheat Ducati's were running 916's! Better yet, as a real Ducati enthusiast...you would have known they were running 996's in their 916's! By my calc, that is a nearly 250 cc (33&#37 advantage over their counterparts! They've got chassis advantages in addition to their valve actuation advantage. But I know you're doing your part as a representative of the man now...just don't tell me you can justify a 33% bigger motor. That is embarrassing.
Also, If you saw the most recent round @ Valencia, you would see how closely matched the 999 was against the I4's. Xaus was passing at will in corners on that tight circuit.

How was Ducati Cheating? If they were why didn't they get caught.

As previously stated. The rules at the time stated you could have a 750 inline 4 or a 1000cc twin, Ducati was doing good with the 916 until the 750's got too close so they bumped up to 996/998. (Still making less HP than a 750 I4).

The the I4's lobbied and said we want 1000cc too!! They got that. They make more HP, weigh about the same, torque numbers are closer... They are still having a hard time racing

Ducati's have more torque. Torque equals power to the ground and the ability to power through corners not just on the straights. Traction control has negated that "advantage".

I am getting tired of hearing that I4's are getting the short end of the stick. Your saying that a Twin and an I4 should have equal everything and then it would be "fair". I don't agree. Take a look at the LRRS rulebook. I bet the bike you race isn't "fair" to someone else. Twins make less HP but more Torque. Torque was the equalizer, It isn't a factor anymore.

This BS about Ducati making a I4... yeah they have one in Moto GP, they wouldn't be competative without one the way the rules are written so they adapted. WSB has different rules. No comparison.

I guess Harley and Moto Guzzi should start making I4's as well since those are the "better" engines.

[Awesome]

Why isn't torque a factor on the straights anymore? They don't have an I4 in GP they have a V4. Noone is telling Harley or moto guzzi to build a better engine because they're not on the racetrack telling the association to bend the rules for them. They're not saying give me what i want or I'm taking my toys and going home. Now as far as the 750's, 1000 twins HP and lobbying, how much do you know about this stuff or are you just regurgitating what other people have said?

[highsider]

This BS about Ducati making a I4... yeah they have one in Moto GP, they wouldn't be competative without one the way the rules are written so they adapted. WSB has different rules. No comparison.

I guess Harley and Moto Guzzi should start making I4's as well since those are the "better" engines.

Back when the rules were 750 4 cyl/1000 2 cyl, Honda and Suzuki built V-Twins to stay competitive. They adapted to their environment, instead of asking the race organizations to change the rules for them. Ducati should do the same.

This gets me thinking....why the hell doesn't Ducati build a sweet V-4? It would sound awesome, have a platform to make a whole bunch more power, and solve their problem. I guess its easier to bitch and complain about how unfair everything is.

[Doc]

motorcyclebloggers.com » Twins vs Inline Fours

I still don't see how Ducati would have an unfair advantage by getting more dispalcement?

A twin is 2 cylinders, It can't do the things a 4 can as easily, It does things differently which is part of it's "advantage" Torque from the Powere pulses is the difference.
I guess you guys are right though, Ducati should put a 1000cc Moto GP engine in the Superbike and no one would even come close.

[OreoGaborio]

I still don't get it... you guys all say that V2's and I4's each have their advantages & disadvantages and you can all recognize the fact that they are NOT EQUAL ENGINES based on displacement... why then do you guys expect the rules governing displacement to be equal?

Someone said earlier that Ducati is currently allowed to make changes in their powerplants that the I4's are not allowed to make and they're willing to get rid of those advantages if they can get a displacement advantage. If that's true, it sounds pretty reasonable to me.

[Doc]

Found this...

Road Racer X