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Engine Capacity

The 81mm bore restriction is nothing but a physical rev limiter; so why should they add an additional electronic rev limiter in a control ECU, on top of that? If they did, then they should remove the 81mm limitation which would become redundant. In that case, all engines would be redesigned, so the sensible thing to do is to keep the 81mm rule and not implement additional rev limitation features in a future control ECU. That would leave some freedom to designers at least.



Ducati (Preziosi) love high-revving powerful engines, they have quite a good know how in that area. So I can see that they are trying to strike a balance between the 81mm limit and their own design preferences. It is quite possible that a 930cc capacity is being used, and that they can extract more power from a 930cc 18,000 rpm engine than from a 999cc 16,000 rpm unit, with possible savings in terms of fuel as well. In doing this they remain in known territory, so to speak.



Another benefit for them is that 930cc allows them to contain the height of the cylinder-head units, something important for a 90° V desmo engine.
 
J4rn0 said:
The 81mm bore restriction is nothing but a physical rev limiter; so why should they add an additional electronic rev limiter in a control ECU, on top of that? If they did, then they should remove the 81mm limitation which would become redundant. In that case, all engines would be redesigned, so the sensible thing to do is to keep the 81mm rule and not implement additional rev limitation features in a future control ECU. That would leave some freedom to designers at least.



Ducati (Preziosi) love high-revving powerful engines, they have quite a good know how in that area. So I can see that they are trying to strike a balance between the 81mm limit and their own design preferences. It is quite possible that a 930cc capacity is being used, and that they can extract more power from a 930cc 18,000 rpm engine than from a 999cc 16,000 rpm unit, with possible savings in terms of fuel as well. In doing this they remain in known territory, so to speak.



Another benefit for them is that 930cc allows them to contain the height of the cylinder-head units, something important for a 90° V desmo engine.
Click to expand...



The designers don't want the 81mm rule. Also, the 81mm restriction is regarded as a rev limit, but over time, it won't be. The manufacturers will find ways to maximize cylinder pressure and reduce friction. The rev ceiling will climb in very small increments at incredible development cost. The engines will require frequent rebuilds, and reliability rules will only make things more expensive. F1 was bore limited, but a rev limit was quickly introduced to further cut costs.
 
And you believe that?



Not 999cc, not 998cc. I think it is a generic figure, as in 1000cc class.



Obsfucation at work.................those cunning Italians.
 
Bunyip said:
And you believe that?



Not 999cc, not 998cc. I think it is a generic figure, as in 1000cc class.



Obsfucation at work.................those cunning Italians.
Click to expand...

Not that it makes a hill of beans difference, but a quote from Preziosi



The bike, Preziosi said, used the maximum capacity allowed at 999cc, Splitting hairs, but is the maximum capacity not 1000 cc
 
Then apparently Krop and his fellow journalists have been led up the garden path?
 
Bunyip said:
They are thinking 900 to 930cc. Thats more than 1cc.
Click to expand...

They said the possibility of that being the most efficient was possible. In the end, it came down to the old saying, there is no replacement for displacement. Honda said the same thing early in the game. Journalist did what journalist do, they used it as a tool to sell articles.I personally had no doubts that every one of them would be near the 1000 cc limit.
 
David (Krop), you must have done your sound analysis by now. So is the Ducati 930 0r 999 cc?



Could it be that Ducati purposely put that tacho on the bike in clear view of the journalists to lead them astray? Would they do such a thing?
<
 
Kropotkin said:
My todo list for Jerez includes recording the Ducati to measure the revs. Then I'll tell you. Reports are that they are under the maximum capacity, at between 900 and 930cc, which sounds plausible. The 800s already made plenty of power, benefits of a smaller engine may outweigh added horsepower, without sacrificing torque. But we'll see.
Click to expand...





The results must be in by now...................................
 
Since CRT is running on Spring Valve, they should be allowed to run on bigger engine capacity i.e 1100
 
maybe 1200cc for twins but if the capacity for 4 cyl would be raised none of the superbike engines would work. they would have to make the bore larger/stroke longer which i guess is quite a job.



in my opinion the mistake was to introduce the 1000cc formula for prototypes in 2012 instead of 2013.

800s vs CRT would have made much more sense than having a new set of rules for just one year
 
Ducati may be running a 930cc unit derived straight from the 800, and have a completely new 1000cc engine still in the testing phase. So Preziosi is not really lying when he says the new bike is (going to be) a 1000. The new engine will also be lighter (not being designed to function as a stressed member like the current one) and nobody knows if the angle between the cylinders will still be 90° or less.
 
Due to the difficulty Rossi had on the 800cc Ducati, they weren't sure giving him the extra 200cc in one lump was such a good idea.



He'll get another 60-70cc next round
<
 
cliché guevara said:
maybe 1200cc for twins but if the capacity for 4 cyl would be raised none of the superbike engines would work. they would have to make the bore larger/stroke longer which i guess is quite a job.



in my opinion the mistake was to introduce the 1000cc formula for prototypes in 2012 instead of 2013.

800s vs CRT would have made much more sense than having a new set of rules for just one year
Click to expand...



Totally agreed. But I believe Japanese Manufacturers: Kwak, Suzuki produce 1400 - 4 cylinders..
 
V5Stroker said:
Totally agreed. But I believe Japanese Manufacturers: Kwak, Suzuki produce 1400 - 4 cylinders..
Click to expand...

yes , but if you compare the newest zzr1400 to a s1000rr engine you'll see that they don't put out more power at the top end because they can not rev that high. those engines offer phenomenal torque because of the big capacity and relatively long stroke ,great for accelerating in a straight line in any gear ,but i don't think they would be the best choice for racing,those engines are very very wide. have a seat on a hayabusa and then on a rsv4
<


maybe crts should be allowed to run turbos, that would be fun and real prototyping
<
 
Bunyip said:
The results must be in by now...................................
Click to expand...

They are not. It is a massively complicated operation, sorting the signal from the noise. I am rather dismayed by just how difficult it is.... I'll post a shot of the sound file later.
 
Kropotkin said:
They are not. It is a massively complicated operation, sorting the signal from the noise. I am rather dismayed by just how difficult it is.... I'll post a shot of the sound file later.
Click to expand...



Look forward to it. Thanx
 

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