Estoril testing

BarryMachine · May 7, 2011

Kropotkin said:
Because CF is easier to manage than aluminium, and create reproducible results. They would have ended up with a similar problem. But CF is also preferred because it is much easier to control stiffness than aluminium, you can create a more precise set of stiffnesses than with ally. Its disadvantage is hysteresis, it snaps back into position, rather than rebounding smoothly like a metal, making it very harsh.

I got sooked at like a ..... ( by Rog. Babel. Pidg and co. ) back in 08/09? for saying this ....... but it was pretty speculative back then so it kinda died a death.

But its interesting you bring it up again ......... I gather Ducati have focused on the hysteresis thing then have they? Is this a known thing now ... I guess there have been 2 years of riding since it was "passed sentence on" on here

Its a spooky thing for sure if their problem has been traced down to the hysteresis of the material ........ but hell what an amazing area for development in CF if they manage to get someone onboard to help them

But there would be so much work in it ..... years! ..... if it is the case then Ducati are "up .... creek"

I don't think it would matter how good any rider they have is as a "development rider" ( Ross, Stoner ..... whomever ) thats gunna take too long to rectify for any of the current riders surely. SToner took the right option in going Honda thats for sure.

michaelm · May 7, 2011

Mental Anarchist said:
Michael don't forget that Stoner does not like to hang .... on his employer so in 2009 he always put the blame on himself rather than publicly say the bike was no good. The results in 2009 were still the same for all the other Ducati riders which was bad and this continued through 2010 and so far in 2011.

Are you saying stoner wasn't really ill in 2009?. I for one think he was, and the pattern in early 2009 was that he was competitive for the first part of races and then dropped off, vomited into his helmet etc. I think he was implying that he was crook rather than than that he wasn't riding well or making excuses for the bike.

michaelm · May 7, 2011

J4rn0 said:
Then the only explanation is that Ducati have been incredibly lucky in 2007 and 2008, their most successful years, using those unreliable parts...? For a factory that doesn't know how to do quality control, they should have had more DNFs than others... but actually the Ducatis have not experienced more technical problems than the Japanese bikes, on average (think of Yamaha in 2007...) and Suzuki have fared much worse than them.

Stoner has become a legend at Ducati, and not only for his fantastic speed that made those successes possible.

At the end of last year, Preziosi said that he loved Stoner and was going to miss him, although at times he had felt like strangling him with his own hands... The story of the two identical bikes with identical setups feeling irrimediably different, can be read in more than one way.

I was a ducati man before stoner was born let alone before stoner rode for them, and producing the bike which won the 2007 championship against honda and yamaha was a great achievement and would have been so if thor the god of thunder was riding their bike, let alone any human being. Your implication would seem to be that stoner was temperamental and stubborn, and I can see him deciding a particular bike or chassis was no good and then refusing to budge.

However it cuts both ways, and I think there is also very likely some truth in their previous production method having inconsistent results, and stoner is not the only one to say so. Most who have seen the previous bikes close up including members of this forum have commented on the rather rough appearance, and valentino himself at the start of his tenure somewhat diplomatically remarked that the bikes were true prototypes

.

You are doubtless better informed about ducati than I am, but there was a lot of talk about the steel trellis frame chassis being outmoded and off the pace even prior to 2007, and the common view was that they needed a new chassis design. This looks a little doubtful now, although perhaps they just went for the wrong new chassis design. The current wsbk ducati with a steel trellis frame chassis doesn't look to have any handling disadvantage, although it may well have torque or power delivery advantages which contribute to this . It does seem possible that the L4 engine configuration may have been/still is a significant part of the problem with the handling woes of the motogp bike as you say.

Mental Anarchist · May 8, 2011

michaelm said:
Are you saying stoner wasn't really ill in 2009?. I for one think he was, and the pattern in early 2009 was that he was competitive for the first part of races and then dropped off, vomited into his helmet etc. I think he was implying that he was crook rather than than that he wasn't riding well or making excuses for the bike.

I don't think I implied that Stoner was not ill at all. He was significantly ill for 3 or 4 races and off for 3 races which leaves 11 or 12 races where he was in fair enough condition to race. What I am suggesting is that based on the results of all the other riders bar Stoner is that the Ducati has always been crap and that Stoner never said that his employers had given him a crap bike or used the bike as an excuse for his performance. He often blamed himself for not getting a good set up or for riding poorly and he did in 2010 blame the 2010 Ohlin's and reverted back to 2009 forks. I think the respect he showed Ducati despite what we all know now and then shows how classy he is. Talpa on the other hand would have us all believe something completely the opposite.

J4rn0 · May 8, 2011

michaelm said:
I was a ducati man before stoner was born let alone before stoner rode for them, and producing the bike which won the 2007 championship against honda and yamaha was a great achievement and would have been so if thor the god of thunder was riding their bike, let alone any human being. Your implication would seem to be that stoner was temperamental and stubborn, and I can see him deciding a particular bike or chassis was no good and then refusing to budge.

However it cuts both ways, and I think there is also very likely some truth in their previous production method having inconsistent results, and stoner is not the only one to say so. Most who have seen the previous bikes close up including members of this forum have commented on the rather rough appearance, and valentino himself at the start of his tenure somewhat diplomatically remarked that the bikes were true prototypes

.

You are doubtless better informed about ducati than I am, but there was a lot of talk about the steel trellis frame chassis being outmoded and off the pace even prior to 2007, and the common view was that they needed a new chassis design. This looks a little doubtful now, although perhaps they just went for the wrong new chassis design. The current wsbk ducati with a steel trellis frame chassis doesn't look to have any handling disadvantage, although it may well have torque or power delivery advantages which contribute to this . It does seem possible that the L4 engine configuration may have been/still is a significant part of the problem with the handling woes of the motogp bike as you say.

I do not know if Kropotkin is right regarding the reasons that made Preziosi opt for CF over trellis -- the quality control issue sounds inconsistent to me, I know firsthand that Ducati are a modern factory and they do all the checks on their outsourced and insourced components that any modern factory would do, -- they are certainly not a bunch of easy going chaps playing in a garage!

Anyway, Kropotkin confirms the information I have on CF applied to motorcycles chassis, i.e. that it 'snaps' into place after flexing. That could be a problem, but for sure they have contemplated it and tested accordingly. I am more inclined to consider that the root of Ducati's problems is in the fully stressed engine and chassis-less design.

And the motive behind that peculiar chassis choice is the L 90° engine architecture. Why? Because the L 90° engine takes more space and would make the bike longer, and chassi-less design compensates for that as it allows to make the bike shorter (the swingarm hinges into the engine itself, rather than in a frame that would have to take some additional space).

So the engine L architecture, in the end, is the root of all the other 'peculiar' Ducati choices, that have not been made just to be different...

Keshav · May 8, 2011

J4rn0 said:
I do not know if Kropotkin is right regarding the reasons that made Preziosi opt for CF over trellis -- the quality control issue sounds inconsistent to me, I know firsthand that Ducati are a modern factory and they do all the checks on their outsourced and insourced components that any modern factory would do, -- they are certainly not a bunch of easy going chaps playing in a garage!

Anyway, Kropotkin confirms the information I have on CF applied to motorcycles chassis, i.e. that it 'snaps' into place after flexing. That could be a problem, but for sure they have contemplated it and tested accordingly. I am more inclined to consider that the root of Ducati's problems is in the fully stressed engine and chassis-less design.

And the motive behind that peculiar chassis choice is the L 90° engine architecture. Why? Because the L 90° engine takes more space and would make the bike longer, and chassi-less design compensates for that as it allows to make the bike shorter (the swingarm hinges into the engine itself, rather than in a frame that would have to take some additional space).

So the engine L architecture, in the end, is the root of all the other 'peculiar' Ducati choices, that have not been made just to be different...

I know of course you don't mean that literally - however I expect to some degree they have stuck with certain design aspects

as a result of not having sufficient resources to simply junk this or that engine design, forcing them to dance around the

central problem by using many unique and ultimately interesting looking innovations that for the most part have ultimately not panned out.

In the same situation the Japanese would have more practicably thrown the engine in the crusher and designed something

fresh - from the ground up.

J4rn0 · May 8, 2011

Keshav said:
I know of course you don't mean that literally - however I expect to some degree they have stuck with certain design aspects

as a result of not having sufficient resources to simply junk this or that engine design, forcing them to dance around the

central problem by using many unique and ultimately interesting looking innovations that for the most part have ultimately not panned out.

In the same situation the Japanese would have more practicably thrown the engine in the crusher and designed something

fresh - from the ground up.

The L 90° architecture has some advantages over narrower angle V engines as it is an 'ideal' architecture providing perfect intrinsic balance to the engine (especially in the screaming firing order). The disadvantage is that the engine is inevitably longer than, say, a 72° V.

michaelm · May 8, 2011

J4rn0 said:
I do not know if Kropotkin is right regarding the reasons that made Preziosi opt for CF over trellis -- the quality control issue sounds inconsistent to me, I know firsthand that Ducati are a modern factory and they do all the checks on their outsourced and insourced components that any modern factory would do, -- they are certainly not a bunch of easy going chaps playing in a garage!

Sure, it sounds inconsistent to me also; you don't win world championships against honda and yamaha with bits of old pipe welded together on an ad hoc basis, even if you paint them red.

Ducati corse is undoubtedly a small operation though, and what I do remember they themselves saying is that carbon fibre would enable them to make changes and build new chassis more quickly; dani pedrosa on one occasion paid tribute to honda for building him an entirely new chassis in a week or a fortnight, so perhaps they were looking to match this kind of capability in their rivals.

The engine itself in terms of its operation as an actual engine is beyond reproach, apart from perhaps having been tuned too savagely to make up for the handling deficiencies, and still may be the most powerful. Apart from the advantages it offers in terms of balance I think ducati were also working within the constraints of the V2/L2 engine on which it was based. There is talk, about which you would be better informed than me, of a narrower angle V2 in a forthcoming production bike. Another point for your argument is that the wsbk engine is a V2 rather than a V4.

hawkdriver · May 8, 2011

J4rn0 said:
I do not know if Kropotkin is right regarding the reasons that made Preziosi opt for CF over trellis -- the quality control issue sounds inconsistent to me, I know firsthand that Ducati are a modern factory and they do all the checks on their outsourced and insourced components that any modern factory would do, -- they are certainly not a bunch of easy going chaps playing in a garage!

Anyway, Kropotkin confirms the information I have on CF applied to motorcycles chassis, i.e. that it 'snaps' into place after flexing. That could be a problem, but for sure they have contemplated it and tested accordingly. I am more inclined to consider that the root of Ducati's problems is in the fully stressed engine and chassis-less design.

And the motive behind that peculiar chassis choice is the L 90° engine architecture. Why? Because the L 90° engine takes more space and would make the bike longer, and chassi-less design compensates for that as it allows to make the bike shorter (the swingarm hinges into the engine itself, rather than in a frame that would have to take some additional space).

So the engine L architecture, in the end, is the root of all the other 'peculiar' Ducati choices, that have not been made just to be different...

I don't think it's a knock on the engineers but the limitations of the materials and construction. Ducati don't make the metal and welding will always produce some minor warping due to the high heat. I know they also have this problem in NASCAR, they also use welded tube construction. JB and one of the mechanics did state that one of their other goals for the bike was to reduce parts count and simplify it. As far as the CF snapping back into place and not having flex, this makes me want to know who ducati is working with and why they haven't solved this problem, CF can be combined with any metal to give you whatever characteristics you need. Even Chevrolet uses this technology in parts of the ZR1 chassis which is carbon fiber bonded to aluminum for this exact reason.

michaelm · May 8, 2011

hawkdriver said:
I don't think it's a knock on the engineers but the limitations of the materials and construction. Ducati don't make the metal and welding will always produce some minor warping due to the high heat. I know they also have this problem in NASCAR, they also use welded tube construction. JB and one of the mechanics did state that one of their other goals for the bike was to reduce parts count and simplify it. As far as the CF snapping back into place and not having flex, this makes me want to know who ducati is working with and why they haven't solved this problem, CF can be combined with any metal to give you whatever characteristics you need. Even Chevrolet uses this technology in parts of the ZR1 chassis which is carbon fiber bonded to aluminum for this exact reason.

There are many more knowledgeable than me regarding this on the board, including actual engineers, but I think the requirements of carbon fibre in a race bike, as opposed to a race car where the science is well worked out, are different, including the necessity for a race bike chassis to flex to some degree particularly when leaned, whereas rigidity is a positive in a car.

I agree that ducati probably should have worked out how to modify a carbon fibre chassis with predictable responses before using one in their race bike.

hawkdriver · May 8, 2011

michaelm said:
There are many more knowledgeable than me regarding this on the board, including actual engineers, but I think the requirements of carbon fibre in a race bike, as opposed to a race car where the science is well worked out, are different, including the necessity for a race bike chassis to flex to some degree particularly when leaned, whereas rigidity is a positive in a car.

I agree that ducati probably should have worked out how to modify a carbon fibre chassis with predictable responses before using one in their race bike.

Yes I agree that cars and motorcycles are different but you should be able to tell an engineer who is experienced in the use of composites that you need a structure built to x spec. I think Ducati just have no idea what x is because they've been using what is probably the simplest way to build motorcycles just welding steel tubes together. Composites have been around for a long time now, they should go talk with someone with a background in composite/material and structures. They could probably even find some laid off or retired aerospace guys for cheap. I've seen these guys come up with some amazing .... when it comes to composite helicopter blades, titanium mixed with carbon fiber and nomex, and this was in the eighties.

The reason I brought up the ZR1 is because unlike most cars that use carbon fiber, Chevrolet wanted damping in the body for daily drive ability/comfort, so they bonded aluminum to their carbon fiber.

alex29 · May 9, 2011

Back in 2008 Catalunya post race test Stoner tested a carbon fibre and an aluminium chassis.What happened to that chassis? Why don't Ducati roll out that frame for Rossi to test?

J4rn0 · May 9, 2011

Badfish said:
Back in 2008 Catalunya post race test Stoner tested a carbon fibre and an aluminium chassis.What happened to that chassis? Why don't Ducati roll out that frame for Rossi to test?

It is possible that it could already have been in the 2012 bike they tested at Jerez. The new inverted swingarm looked certainly like aluminum, and if they revert to Al for the swingarm, why not for the front subframe as well. After all the comparison tests between CF and Al have been made by Stoner and Hayden, not by Rossi. They came to the conclusion that there was no difference, but Rossi might have asked to compare them himself.

Tom · May 9, 2011

J4rn0 said:
Was Furusawa referring to CF when he said that Ducati 'are doing something wrong'? Or to the 90° L engine architecture, that makes the bike longer? Who knows.

I read somewhere, possible even something by Kropo about the 90 degree engine that Ducati use giving them very short front engine mounts compared to their competitors, which ties in somewhat with the trend that all the teams took in the 990 era to make their front engine mounts longer to improve chassis behavior. Maybe Ducati need to narrow that v angle

J4rn0 said:
The mini-frame connecting the cylinder heads to the steering head was in steel trellis before, not in aluminum. Only the swingarm was aluminum. They first changed the front frame to CF, then the swingarm as well. From what I saw of the 2012 prototype, the new inverted swingarm looks like aluminum though.

They did make an aluminium monocoque around the same time they were introducing the carbon one.

Kropotkin said:
Because CF is easier to manage than aluminium, and create reproducible results. They would have ended up with a similar problem. But CF is also preferred because it is much easier to control stiffness than aluminium, you can create a more precise set of stiffnesses than with ally. Its disadvantage is hysteresis, it snaps back into position, rather than rebounding smoothly like a metal, making it very harsh.

So even if the CF is tuned to deform at the same rate under load, its rebound characteristic is far less ideal? I seem to recall something where Furusawa said that one day a damped CF chassis might be the ideal solution.

Kropotkin · May 9, 2011

They use aluminium subframes for rapid prototyping, test the basic properties, then reproduce them in CF. It's much quicker to make an ally part than a CF part.

J4rn0 · May 9, 2011

Kropotkin said:
They use aluminium subframes for rapid prototyping, test the basic properties, then reproduce them in CF. It's much quicker to make an ally part than a CF part.

Yes, and that makes it easy to compare the behavior of the two. Now suppose Rossi after the comparison tells them, -- I actually liked the aluminum better. What do you think they will do? The CF choice is the only one that could have been dictated by marketing. Trellis was and is a Ducati trademark; now if you decide to move away from that, but still want to be different from the Japanese, then you end up choosing CF probably. I see a technical reason one may prefer 90° L engines, this in turn can dictate the fully stressed engine to contain the length of the bike; but the choice of CF puzzles me.

Mental Anarchist · May 9, 2011

J4rn0 said:
Now suppose Rossi after the comparison tells them, -- I actually liked the aluminum better. What do you think they will do?

Airbrush it to look like carbon fibre.

michaelm · May 9, 2011

Kropotkin said:
They use aluminium subframes for rapid prototyping, test the basic properties, then reproduce them in CF. It's much quicker to make an ally part than a CF part.

I believe it is possible to alter aluminium on the fly as well since it can be bent/sawn/welded etc, whereas once you have baked carbon fibre you are stuck with what you have. It looks to me that they came up with a pretty good design for the 2009 chassis, replicated it in carbon fibre, but when it came to the 2010 bike there was some unexpected interaction between the carbon fibre chassis and the bigbang engine and whatever else they altered to make the bike "more rideable", and possibly the 2010 bridgestone tyres. As I recall they were said to have deliberately altered thefront/rear balance of the bike in any case. Perhaps they didn't do enough preliminary work in aluminium, which begs the question as to why they didn't just stick to aluminium, given that the benefits of going carbon fibre thus far seem entirely theoretical.

michaelm · May 9, 2011

hawkdriver said:
Yes I agree that cars and motorcycles are different but you should be able to tell an engineer who is experienced in the use of composites that you need a structure built to x spec. I think Ducati just have no idea what x is because they've been using what is probably the simplest way to build motorcycles just welding steel tubes together. Composites have been around for a long time now, they should go talk with someone with a background in composite/material and structures. They could probably even find some laid off or retired aerospace guys for cheap. I've seen these guys come up with some amazing .... when it comes to composite helicopter blades, titanium mixed with carbon fiber and nomex, and this was in the eighties.

The reason I brought up the ZR1 is because unlike most cars that use carbon fiber, Chevrolet wanted damping in the body for daily drive ability/comfort, so they bonded aluminum to their carbon fiber.

There was talk ferrari were involved initially with the carbon fibre approach.

There has never previously been a successful carbon fibre race bike, and so the problems may be unique; jb has said they have only now worked out how to alter carbon fibre with predictable results in terms of the effect on the bike. Going on what he said last year whilst still with yamaha ,and it seemed before any decision to go to ducati, the new forks used by yamaha last year required very extensive testing to get right before being used on the race bike, and hence he was unsurprised with ducati's difficulties with similar forks, contrasting unfavourably the resources available to them vs yamaha. Presumably going both to the integrated engine chassis and carbon fibre were much more radical changes.

hawkdriver · May 9, 2011

michaelm said:
There was talk ferrari were involved initially with the carbon fibre approach.

There has never previously been a successful carbon fibre race bike, and so the problems may be unique; jb has said they have only now worked out how to alter carbon fibre with predictable results in terms of the effect on the bike. Going on what he said last year whilst still with yamaha ,and it seemed before any decision to go to ducati, the new forks used by yamaha last year required very extensive testing to get right before being used on the race bike, and hence he was unsurprised with ducati's difficulties with similar forks, contrasting unfavourably the resources available to them vs yamaha. Presumably going both to the integrated engine chassis and carbon fibre were much more radical changes.

I don't remember if it was last year or the year before but JB has said something about the yamaha being so good because they designed the chassis around the forks, unlike Ducati who designed their chassis then added the forks only to find out it didn't work, then they had to try going back to the previous years forks. Was it last year that Ducati was switching forks back and forth on Stoner's bike? I really think they're going to learn a lot from JB just because he's been around watching how yamaha has solved so many problems. I wouldn't be surprised to find out Furusawa is helping a little too because of the love fest he has with Rossi.

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