Ducati goings on. Part 2.

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Re: Ducati goings on. Part 2.

Postby freighttrain on Thu May 03, 2012 6:55 am

nice post Zaphod....
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Re: Ducati goings on. Part 2.

Postby tom on Thu May 03, 2012 7:20 am

I think the last Zaphoid posts were spot on. Also a lot less ........ in them which makes reading them a lot easier :D ;)
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Ducati goings on. Part 2.

Postby Gustav O on Thu May 03, 2012 7:35 am

tom wrote:I think the last Zaphoid posts were spot on. Also a lot less ........ in them which makes reading them a lot easier :D ;)

Agreed, especially regarding the ..... :)
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Re: Ducati goings on. Part 2.

Postby Hanuman on Thu May 03, 2012 7:43 am

RatsMC wrote:
Huh? We know that to increase RPMs when trying to increase displacement requires an increase in bore once you've hit the max piston speed (~26M/second). That means the bore is a "freebie" when counting rotations. Since 81mm is the limit on bore and 81mm doesn't present huge engineering problems in terms of combustion, it seems completely illogical to consider that any of the factories would use anything but an 81mm bore. So, the assumption is sound.

Given that and the reported RPMs, the calculations are also sound. In order to rev higher than the competition with consideration to the 81mm bore limit, you've only got one option: reduce displacement.

This also explains at least a little bit of the power delivery issue the riders have complained about.


Why the "Huh?"
Isn't all that what I wrote: "Seems to be a based on assumed bore size, an assumed max mean piston speed and a decent analysis of max rpm". Perhaps you're taking 'assumption' as a perjorative? I was surprised that from Geonerd's link, it would seem that the speculation began with an observation of a tacho scale.

Kinda off-topic: Why assume 26m/s as a maximum MPS? After all, NASCARs with 4.185" bore x 3.25" stroke run higher MPS than 26m/s....Note we're talking Mean Piston Speed here not Max Piston speed, that'd be 30+ m/s ...
MPS is really an indicator of the potential an engine might have. It's a good number to use to examine the theoretical performance of an engine, but not an actual indicator of the specific limitations an engine may have. That is, what specifically is the limitation that Mean Piston Speed represents?
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Re: Ducati goings on. Part 2.

Postby Zaphod on Thu May 03, 2012 8:25 am

MPS is one factor in regards to possible difficulties regarding the way the poer comes in.

The quandry I have is, usually, the smaller the displacement and the higher the revs, the narower your power/torque band is. Classically, a bigger displacement will give you better lowdown power, but peak earlier in the rev range.

Where I'm getting confused is, the thing revs like all get out and has plenty of top end power/speed, yet the riders are complaining of the abrupt way the power comes in down low. What would help is if anyone has data or footage to show what rev's the riders are calling "lowdown" when exiting a corner. If we break it down to 2 stroke equiviallity, then I could imagine if their version of "lowdown" is still up around 10 to 12 00rpm, it would be more to do with cam lift/duration angles in conjunction with tuned length of the header pipes, ie gas flow, making it "snap" into powerband, rather than a linear (for arguments sake) progresion that maybe yamaha and honda have.

I take some solace in seeing that, although the carbon frame may not have been the cause of the issues, by removing it ( and it's own quirks that need to be sorted) they have isolated (time will tell) where the root cause of the problems seem to lie. I thought at the time (and said as much.....mug's guess) that although the frame may or may not have been the problem, removing it would be a step I would take, if for no other reason than to simplify the equation.

At the start, I could see that it would be easy to get lost in trying to identify the problem..........is it the frame ? Is it the suspension/tyres ? Is it the engine ? Once they get this power delivery issue sorted, then you could, in all probability, return to the CF design knowing that any issues you were then trying to solve were purely geometry/flex etc related.


I hope the CF does come back..........when the bike is working better.

Don't bite off more than you can chew.

Thanks for the compliments. My new approach is to try not to criticise people who live that existance, and have greater ability than myself. Look for the positives, and really try to look at the issue subjectively.


......With the exception of Marquez's current trick of shoving people onto ripple strips to get by while costing them time. That's an arse of a manouvre. Nice work by Redding in showing him the best way to cost someone time is to shove yourself, and the following freight train up the inside in a slow corner.

Classy payback from the young man.

Worried Marquez is going to keep doing this until someone gets hurt. It took my breath away to watch Redding on a wet ripple strip. Maximum credit to him for

a) still being able to pull it up and fall in behind

b) Not sinking to Marquez's level.

Critique ends. :D
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Re: Ducati goings on. Part 2.

Postby RatsMC on Thu May 03, 2012 8:28 am

Hanuman wrote:
Why the "Huh?"
Isn't all that what I wrote: "Seems to be a based on assumed bore size, an assumed max mean piston speed and a decent analysis of max rpm". Perhaps you're taking 'assumption' as a perjorative? I was surprised that from Geonerd's link, it would seem that the speculation began with an observation of a tacho scale.

Kinda off-topic: Why assume 26m/s as a maximum MPS? After all, NASCARs with 4.185" bore x 3.25" stroke run higher MPS than 26m/s....Note we're talking Mean Piston Speed here not Max Piston speed, that'd be 30+ m/s ...
MPS is really an indicator of the potential an engine might have. It's a good number to use to examine the theoretical performance of an engine, but not an actual indicator of the specific limitations an engine may have. That is, what specifically is the limitation that Mean Piston Speed represents?



But you don't even need to do any math to figure that is the Ducati is revving higher it is a smaller displacement.
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Re: Ducati goings on. Part 2.

Postby dave_m on Thu May 03, 2012 9:07 am

Zaphod wrote:With Qualifying being what it is, in so far as if you manage one quick lap (in variable conditions), and then during the race, by really hanging your neck out, you manage to stay with the fast bikes for three laps until their tyres warmed up, at which point they just rode away to leave you one place higher than your team-mate, I'd still take both sets of data into account.

Be realistic about it. All Hayden's efforts (no critique of rider implied or intended) amounted to was a gap 6-odd seconds up the road from his team-mate. One started back and went forwards a bit, one started forwards and went back alot.

They both sound like they know where the issue is............power delivery. That's what both riders are implying is responsible for the tyre degradation and handling issues. Two different riding styles and approaches are pointing to the same underlying issue........... as well as resulting in both bikes finishing every race in close proximity to each other.

Why is Hayden the saviour all of a sudden, after one good effort ?

...

I also belive having two sets of data is going to help you more than having just one set.



That's pretty much the point, there's no reason the data from either one is more valuable. Hayden appears to have started the weekend with a slightly better setup based on qualifying, but Rossi appears to have adapted to it and improved on that "ducati setup" in the race. Hopefully they have some dry practice time, as well as a dry test after Estoril to see if they actually made progress. They've been so up and down over the last year, I think I'll need to see the Ducati Factory team perform well for 3 dry race weekends in a row before I'll believe anythings actually fixed.
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Re: Ducati goings on. Part 2.

Postby Hanuman on Thu May 03, 2012 9:12 am

RatsMC wrote:
But you don't even need to do any math to figure that is the Ducati is revving higher it is a smaller displacement.


Pardon?
So Smaller capacity = higher revs. Ceteris Paribus, perhaps.
But nothing in engines ever are.

Again, I've not said that the Ducati hasn't reduced capacity to chase horsepower via revs. I've just questioned the use of 26m/s MPS as the method to determine that reduction.
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Re: Ducati goings on. Part 2.

Postby freighttrain on Thu May 03, 2012 9:56 am

Zaphod wrote:I take some solace in seeing that, although the carbon frame may not have been the cause of the issues, by removing it ( and it's own quirks that need to be sorted) they have isolated (time will tell) where the root cause of the problems seem to lie. I thought at the time (and said as much.....mug's guess) that although the frame may or may not have been the problem, removing it would be a step I would take, if for no other reason than to simplify the equation.

At the start, I could see that it would be easy to get lost in trying to identify the problem..........is it the frame ? Is it the suspension/tyres ? Is it the engine ? Once they get this power delivery issue sorted, then you could, in all probability, return to the CF design knowing that any issues you were then trying to solve were purely geometry/flex etc related.
I hope the CF does come back..........when the bike is working better.

....With the exception of Marquez's current trick of shoving people onto ripple strips to get by while costing them time. That's an arse of a manouvre. Nice work by Redding in showing him the best way to cost someone time is to shove yourself, and the following freight train up the inside in a slow corner.

Classy payback from the young man.

Worried Marquez is going to keep doing this until someone gets hurt. It took my breath away to watch Redding on a wet ripple strip. Maximum credit to him for

a) still being able to pull it up and fall in behind

b) Not sinking to Marquez's level.

Critique ends. :D


i agree with you on Ducati's removal of the carbon frame from the equation to lower the amount of variables while trouble shooting... and i too hope that it makes a return..

And i also agree with the Marquez analysis... to be honest, i see Marquez looking past his current competition and towards MOTOGP already. Would be fun to actually see him fight to the end and come up short for the MOTO2 Title...

when it comes to the power delivery with these bikes in MOTOGP... how much can be altered by the electronics... and how much may end up being a mechanical revision of the power-plant?

With all of the talk about the power delivery from Hayden and Rossi... is Ducati simply chasing their tail with the electronics trying to control the motor's delivery?... or do you think that the problem exists by the design of the motor itself?
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Re: Ducati goings on. Part 2.

Postby Zaphod on Thu May 03, 2012 1:17 pm

From what they are both saying, it is to do with the engine itself. They don't believe electronics can deal with the problem completely, and they'd know more than anyone. As per my quote from the previous page, Rossi and Hayden are going to try some new bits for, or at the test immediately after, Estoril. Depends when the bits turn up. In the quote he says it's not a new engine, more some component mods than anything.

I may be missing something, but it is quite easy to imagine that if the power delivery is abrupt, when you first open the throttle (before the rear has the oportunity spin up) that the sudden increase in power is going to push the front into understeer (depending on the riders style), then as the power keeps increasing, one would presume exponetionaly, the rear breaks out and causes problems getting off the turn.

This scenario would, conceivably, result in the side product of tyres heating up quick, and going off quick.

Depending on how the electronics govern , or smooth out, the power, trying to get them to compensate for this eventuality might lead to too much softening of power....with the expected time loss incured due to the excess govening.

Better to sort out, as best you can, the actual problem, then bring the electronics into the equation. Much like they have done with the carbon frame side of things.

Just how I see it. Probably wrong.


My opinion on the whole shebang is, the bikes been bad for 5 to 6 years. It's going to take, you would think, two seasons to start getting it right.

By right, I mean achieve the same result that Rossi and Burgess got at Yamaha. That's now a bike that most can use to full effect.

As a side note, or stupid opinion, Jarvis's attitude is starting to bug me. He seems quite happy to revel in the performance of a bike that was rubbish until he employed the people who he is now quite happy to deride , in small, snide ways.

Much prefer Lorenzo's attitude. He is quite open about just how much he learnt from having Rossi as a team-mate, whatever their personal differences may or may not be.

Anyway, just an opinion...........
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Re: Ducati goings on. Part 2.

Postby Gustav O on Thu May 03, 2012 2:02 pm

Zaphod wrote:As a side note, or stupid opinion, Jarvis's attitude is starting to bug me. He seems quite happy to revel in the performance of a bike that was rubbish until he employed the people who he is now quite happy to deride , in small, snide ways.

I think you are making a to big deal out of Rossi/Burgess importance on the development of the M1 and discarding Furusawas importance. Rossis praise for Masao is possibly even stronger than for JB and Yamaha did also step up their game in every aspect for the 2004 season and have had a good directions since.

Anyway, just another opinion.
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Re: Ducati goings on. Part 2.

Postby Zaphod on Thu May 03, 2012 2:20 pm

I agree.

Something about Jarvis is irking me though.

I don't think the yamaha would be anywhere without all three, Furusawa, JB and Rossi. each vitally important, the reason I don't include Yamaha themselves is that I got the impression that Furusawa used the prescence and requests of Rossi and co to get Yamha Corporate to follow through on what he probably was trying to achieve anyway.

The "opinion" bit was refering to me, and my personal (probably wrong and ill-informed) take on how Jarvis is coming across these days.
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Re: Ducati goings on. Part 2.

Postby Gustav O on Thu May 03, 2012 2:29 pm

Zaphod wrote:The "opinion" bit was refering to me, and my personal (probably wrong and ill-informed) take on how Jarvis is coming across these days.

I understood and figured I´d give my slightly different view. I think Jarvis has been doing most things right since he started. Yamaha has a very strong bike and a lot of strong riders.
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Re: Ducati goings on. Part 2.

Postby Zaphod on Thu May 03, 2012 2:32 pm

I like different views, as they help me to learn, as well as combat my own biased opinions.


To get back on track, what effect does anyone see Germany invading Italy having on the whole Super Duc racing effort ?
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Re: Ducati goings on. Part 2.

Postby Sloth27 on Thu May 03, 2012 3:12 pm

Zaphod wrote:I like different views, as they help me to learn, as well as combat my own biased opinions.


To get back on track, what effect does anyone see Germany invading Italy having on the whole Super Duc racing effort ?


Probably none for at least a year or two. These takeovers I imagine are fairly complex and I think it will take some time before anyone at Audi has a say in operational changes at Ducati. It will remain effectively as is because Audi bought the company for branding/prestige reasons, so the racing program probably plays a big part in that.

In the long term, the focus might shift back to WSBK and the MotoGP team will go.

Then again, if Aprilia and BMW ever enter as factory teams, Audi would be keen to stick around...
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Re: Ducati goings on. Part 2.

Postby TwoStroke Institute on Thu May 03, 2012 4:04 pm

Stroke is what governs max rpm not piston speed. The difference in stroke between a 81mm bore 930 and 1000 is 3mm on a very short stroke engine which is negligable. Ducati would just have a higher rpm limit.
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Re: Ducati goings on. Part 2.

Postby Rossifumi on Thu May 03, 2012 5:22 pm

Gustav O wrote:
Zaphod wrote:As a side note, or stupid opinion, Jarvis's attitude is starting to bug me. He seems quite happy to revel in the performance of a bike that was rubbish until he employed the people who he is now quite happy to deride , in small, snide ways.

I think you are making a to big deal out of Rossi/Burgess importance on the development of the M1 and discarding Furusawas importance. Rossis praise for Masao is possibly even stronger than for JB and Yamaha did also step up their game in every aspect for the 2004 season and have had a good directions since.

Anyway, just another opinion.

Furusawa has high praise for Rossi too. Lets not forget that during the 2004, 2005, 2006 and 2007 seasons only Rossi managed to win on the Yamaha - quite a few winners, on both factory and sattelite bikes, won on the Honda in the same time period. So Furusawa may well have done a good job but maybe Rossi/Burgess flattered the bike in the early days too? Jarvis and Yamaha owe them a lot.
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Re: Ducati goings on. Part 2.

Postby Gustav O on Thu May 03, 2012 5:36 pm

Rossifumi wrote:Furusawa has high praise for Rossi too. Lets not forget that during the 2004, 2005, 2006 and 2007 seasons only Rossi managed to win on the Yamaha - quite a few winners, on both factory and sattelite bikes, won on the Honda in the same time period. So Furusawa may well have done a good job but maybe Rossi/Burgess flattered the bike in the early days too? Jarvis and Yamaha owe them a lot.

They are of course all part of the process but Yamaha had one outstanding rider and a bunch of support riders who didn´t win much before or after riding the Yamaha ( Checa, Edwards, Abe, Elias, Xaus etc. etc.) When they got two great riders the bike started winning with them on as well.
I am not trying to discredit Rossi or Burgess here, just trying to point out how important Furusawas and Yamahas effort was.
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Re: Ducati goings on. Part 2.

Postby Rossifumi on Thu May 03, 2012 5:54 pm

Gustav O wrote:
Rossifumi wrote:Furusawa has high praise for Rossi too. Lets not forget that during the 2004, 2005, 2006 and 2007 seasons only Rossi managed to win on the Yamaha - quite a few winners, on both factory and sattelite bikes, won on the Honda in the same time period. So Furusawa may well have done a good job but maybe Rossi/Burgess flattered the bike in the early days too? Jarvis and Yamaha owe them a lot.

They are of course all part of the process but Yamaha had one outstanding rider and a bunch of support riders who didn´t win much before or after riding the Yamaha ( Checa, Edwards, Abe, Elias, Xaus etc. etc.) When they got two great riders the bike started winning with them on as well.
I am not trying to discredit Rossi or Burgess here, just trying to point out how important Furusawas and Yamahas effort was.

look who won on the Honda in the same time period: Gibernau, Max, Tamada, Elias, Melandri, Barros, Hayden, Pedrosa. Quite a few of them compared to just one Yamaha rider, mostly not wildly different and Elias and Melandri featured on both bikes.
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Re: Ducati goings on. Part 2.

Postby Rusty Bucket USA on Thu May 03, 2012 6:22 pm

Moderator Edict:
This thread is already way too huge. We can't have this thing add 5 pages after every race.
Let's please not talk about Moto 2, Yamaha and Honda, and/or anything that is specific to a race. FWIW, this thread is about larger, overall trends with Ducati and more or less technical stuff about the bike. I fell into the trap, too, but lap-by-lap analysis should go in the individual race threads.
The internal combustion engine was not put on wheels just to rest the horses.
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Re: Ducati goings on. Part 2.

Postby Rusty Bucket USA on Thu May 03, 2012 6:29 pm

It seems like some of you missed this:
Gustav O wrote:... I think it is strange to say that the riders input and data is NOT valuable for the team. What else do they have to work from? Imaginary information if they would have gone faster?
The internal combustion engine was not put on wheels just to rest the horses.
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Re: Ducati goings on. Part 2.

Postby Rusty Bucket USA on Thu May 03, 2012 6:31 pm

redmike34 wrote:Let's use Nicky as the constant over the last four years--the following numbers represent the average gap to race winner, best gap to race winner, worst gap to race winner for Nicky since 2009, all in seconds. This excludes the three races in which he got lapped, any race he didn't finish, and is not adjusted for weather, etc.:
2009: 37.2, 12.9, 61.2
2010: 19.3, 1.9, 50.7
2011: 36.9, 23.0, 76.3

2012 is only two races old, but it isn't reminding me of 2010 just yet. For Nicky, at least, the Ducati seemed to progress significantly from 2009-2010.

This is an excellent point. It confirms what memory always suspected.

Whether or not Hayden is improving, I think there is something to be gleaned from his own comments. Even though his performance is not (yet) as good as 2010, he is expressing more optimism about the feel and potential of this bike. He may be wrong about that, having his perspective skewed by last year's bike, but for now, the reason he figures prominently in the discussion is that he has something important to say.

Also, this is a semantic point, but the phrase "bike built for one rider" is, as we have seen, drastically different than "a bike only one guy could ride". It is clear that none of the Desmosedicis were built for Stoner, conversely it is clear that he is fast on anything he rides.
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Re: Ducati goings on. Part 2.

Postby Hanuman on Fri May 04, 2012 1:16 am

TwoStroke Institute wrote:Stroke is what governs max rpm not piston speed. The difference in stroke between a 81mm bore 930 and 1000 is 3mm on a very short stroke engine which is negligable. Ducati would just have a higher rpm limit.


Indeedy.
Which gets back to Zaphod's comments - chasing horsepower via revs and losing tractibility in the lower ranges.
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Re: Ducati goings on. Part 2.

Postby dave_m on Fri May 04, 2012 1:46 am

Hanuman wrote:chasing horsepower via revs and losing tractibility in the lower ranges.


So how much of Ducati's throttle response problems would just be fixed by trying to get 260HP out of a 1000cc engine instead of 280HP out of 920cc engine? (Updated HP numbers from here.)
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Re: Ducati goings on. Part 2.

Postby Hanuman on Fri May 04, 2012 2:27 am

dave_m wrote:
Hanuman wrote:chasing horsepower via revs and losing tractibility in the lower ranges.


So how much of Ducati's throttle response problems would just be fixed by trying to get 240HP out of a 1000cc engine instead of 250HP out of 920cc engine?


If I knew that, I'd be knocking on doors in the western suburbs of Bologna!

The problem is understanding where the power delivery issues come from. Simplistically, if they have chased the high rev power option, the breathing characteristics (valve timing/lift, exhaust dimensions) are going to be optimised to getting it to work at the circa 17K rpm.
Surely, as Zaphod has suggested, this compromises delivery at the lower ends of the curve, somthing that can be smoothed over to a certain extent by electronics...but clever ignition and injector algorithms won't be able to fill all the gaps.

Assuming they do have a smaller displacement engine and aren't just ragging the hell out of a longer stroke (which remains a possibility), to go back to a 1000 means a revisit of almost everything from the bottom end up.
Revised crank, re-evaluation of the bore/stroke, conrods, pistons, valve gear...and then all the attendent injectors, remapping, on and on. As I've written before, so much of what Ducati is doing is on the fly, compared to the (relatively) evolutionary development of the Honda and Yamaha, I don't think they are in a position to really get into the nitty gritty of where they are.

Simplistically, development is change-one-thing-at-a-time so you can evaluate the effects...Duke is running at a million miles per hour with little opportunity for deep contemplation (if they are inclined to comtemplate at all....)

A possibility that I've considered (based on nothing more than reports of Ducati's corporate pride) is that they're so hung up on the high rev advantages of desmodromics that it's the development path they take by default.
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