Ducati Sporting Club UK > DesmoDue Race Series > DesmoDue - General Questions and Chat > No Modifications - what does it mean

[skidlids]

Originally Posted by JasonBoswell

There's no denying that bike goes like f*** since the work was done though. So presumably there's a lot of performance to be gained from having the engine apart and blue-printing, its not just about reliability.

Who said it has been Blue printed, thats new to me

[Senna3]

Originally Posted by JasonBoswell

There's no denying that bike goes like f*** since the work was done though. So presumably there's a lot of performance to be gained from having the engine apart and blue-printing, its not just about reliability.

so in that case i must be cheating as well because my bikes farster than yours still not as much as cleggy and andy challis and dallas and miss riot and tp because i couldent beat them and as for matt he must of had a 800 engine for sure

[bradders]

Originally Posted by Senna3

i must be cheating as well

definitely!!

[Senna3]

dam ive been found out best i remove the 900engine second thouthts it standard as it came from the factory so it must be ok

[rossco572]

glad to see the lighter element returning to his thread. was beginning to think i needed body armour in my race kit !

[Jolley]

Originally Posted by nelly

Just an aside though, if the RC do clarify the issue, and just suppose it was ruled against, how the hell would you check it?

I am not sure it needs checking. If there is to be a random dyno testing session at one of the rounds we will see if anyone has too much go in their motor. At that point it can be decided what to do with that bike.

Also, if Nog starts winning every round by half a lap we might look into it.......

In all seriousness though, I doubt we should be too bothered by anyone else's bike. I have checked mine to see it is as close to the 53bhp limit as possible for the following reason: I do not have the skill to take apart the engine, so this was the easiest way of me checking to see there was no outragous power. If the bike had been obviously over the 53bhp I would have had someone look at it to check there was nothing illegal (Not easy to know on a bike raced by 2 different owners). I suggest scrutineering works the same.... all bikes, or any suspected of too much power, are tested on a dyno at one of the rounds.

As for the money aspect, I do not see the argument. If you have a bike as close to the power and weight limits as possible, realistically no other rider can have a faster bike than you regardless of the money spent. As I have said before (and others on here have said), the top finishers could finish top on 70% of the bikes on the grid.

[Rattler]

Originally Posted by Jolley

I am not sure it needs checking. If there is to be a random dyno testing session at one of the rounds we will see if anyone has too much go in their motor. At that point it can be decided what to do with that bike.

Also, if Nog starts winning every round by half a lap we might look into it.......

In all seriousness though, I doubt we should be too bothered by anyone else's bike. I have checked mine to see it is as close to the 53bhp limit as possible for the following reason: I do not have the skill to take apart the engine, so this was the easiest way of me checking to see there was no outragous power. If the bike had been obviously over the 53bhp I would have had someone look at it to check there was nothing illegal (Not easy to know on a bike raced by 2 different owners). I suggest scrutineering works the same.... all bikes, or any suspected of too much power, are tested on a dyno at one of the rounds.

As for the money aspect, I do not see the argument. If you have a bike as close to the power and weight limits as possible, realistically no other rider can have a faster bike than you regardless of the money spent. As I have said before (and others on here have said), the top finishers could finish top on 70% of the bikes on the grid.

Yeh - kind of - efficiencies in engines and balancing / weight reduction etc, can mean that although these engines do not make any more power (that could be measured on a dyno), they can make this power more easily and quicker. So as a result the bikes they are fitted with these engines can be faster (they get up to speed quicker) than those bikes that are not so well "balanced" or don't use lighter-weight engine components.

But as many have said, the differences that fitting a lighter/balanced crank and/or a lightened/balanced flywheel (both of which are illegal) won't necessarily make any difference in the real DD world (as the differences are relatively slight) and these won't show up on a dyno.

If a 583 could be made (within the rules) to produce more than 53bhp (and still be legal), then the challenge would be how to optimise that bike to make more power lower in its rev range (effectively better torque) and still fall below the 53bhp thresh-hold at the top end. you're then in the land of exhaust mods (2-1,2-2 etc) and other areas.

But - Its the Indian, not the arrow.
Tim

[ChrisBushell]

Originally Posted by Senna3

i recon miss riot weighs about 7 stone so she should have to wear a five stone lead belt to equal my weight as for dom he will have to cut one of his legs off

Cruel!!!!

[Fastfasulli]

Sorry to be boring and serious but:
I would just like to say congratulations to Skidlids for opening this subject for debate. If Kev wasn't asking the questions in an open forum what would be left but gossip and rumour. It's good that it's being done before the season starts too.

That is all...

[ChrisBushell]

Originally Posted by Rattler

Yeh - kind of - efficiencies in engines and balancing / weight reduction etc, can mean that although these engines do not make any more power (that could be measured on a dyno), they can make this power more easily and quicker. So as a result the bikes they are fitted with these engines can be faster (they get up to speed quicker) than those bikes that are not so well "balanced" or don't use lighter-weight engine components.

But as many have said, the differences that fitting a lighter/balanced crank and/or a lightened/balanced flywheel (both of which are illegal) won't necessarily make any difference in the real DD world (as the differences are relatively slight) and these won't show up on a dyno.

If a 583 could be made (within the rules) to produce more than 53bhp (and still be legal), then the challenge would be how to optimise that bike to make more power lower in its rev range (effectively better torque) and still fall below the 53bhp thresh-hold at the top end. you're then in the land of exhaust mods (2-1,2-2 etc) and other areas.

But - Its the Indian, not the arrow.
Tim

Very well put mate!

In part here we are looking at an area that at present no modification is allowed to the crankshaft, its flywheels and the seperate flywheel.

We do already know that fitting a light weight flywheel, makes the bikes spin up faster out of the corners and confers an advantage, hence the reason that they are not allowed.

If any form of machining to the crankshaft was to be allowed, so as to allow the entrant to "balance" the reciprocating mass, then that opens the way for people to remove "excess" weight from the crankshaft "during" the balancing process. I would be interested in hearing suggestions as to how the rules could be written to ensure that this option was controlled effectively.

Now about 20 years ago when I last had my Jaguar engine apart, I had the whole crankshaft assembly (from front damper through to the clutch pressure plate) dynamically balanced. The engine was subsequently significantly smoother and appeared to spin up easier. This is on a 6 cylinder 3.5 litre long stroke engine! Every component came back with little drill marks all over them where metal has been removed, not just in the original places that the factory had machined them.

Was it money well spent? Well I cant remember how much it cost me, but I beleive that it was worth it. Would have it been legal in Desmo Due - no way under the current rules.

Big-end regrinds

I have just tried a pair of std big-end shells out of my 500 paralyzed twin and the 0.25 regrind ones on the scales. Now the scales aren't that accurate, but it would appear that the 0.25 ones are slightly heavier. This is pobably because the backing steel needs to be 0.25 thicker.

Funny thing is that these are the same shells as used in a 620, even though the engine was made in 1977!!!

It would appear that the thicker shells compensate for the metal that we have had to remove from the crankshaft during the grinding process.

I have checked that bikes and my other factory manuals, including the car ones and not one mentions the need to rebalance the crank after grinding it.

Blue printing

I think I worked out that I am now on something like my 42nd Ducati single rebuild, so could assume that in this area I am reasonably knowledgeable. Taking Nelly's earlier point about the above, I am very carefull to assemble the engines to excatly how the factory specified the clearances, shimming and everything else. Doing that has resulted in a line of very strong and reliable engines, without the need to resort to trying to do things "better".

Acording to my notes, we have had two cranks sent off for balancing, after fitting of a new big-end and rod assembly and neither were found to require balancing.



This answer is a personal view and not being expressed with a Race Committee hat on - please bear that in mind!

A number of suggestions have been put forward fior ammendments to the ules in these areas, which we will do our best to work through as quickly as possible.