Quote:
Originally posted by Monty
Quote: Originally posted by mw
i believe all this histeria about a big big bore kit is rider perception not fact ...
the 620 big bore kit gives only v v slight power increase but it does give a wider power band and slightly more torque ... all to keep it on a par with a v well set up big bore 583 (it is not just about fitting a big bore kit and instantly getting the power to be on a par with the 620's you have got to sort the carburation (shorter inlets and flat slide carbs) and set it all up correctly ).
the rules were formulated to allow people 2 choices either don't fiddle and fettle and buy a 620 or buy a 583 and work to get it on a par ... infact the feeling is that the big bore 583 with correct carbs and set up would beat a 620 on power and torque ... hence having the big bore 620 option is important as this would (if you wanted to spend the money) allow one to get even ... it's all v close thou' so the extra expence probably wouldn't be worth it unless running v close to winning the championship ...
the expected power outputs of a sorted big bore 583, standard 620 and big bore 620 are all around 62 -65 bhp however all this about different dyno figures is also very misleading as each dyno has a different reading to the other ... they are useful in evaluating dif engines run on the same dyno as a comparison but not worth it between dif dynos.
also look at sigma's article on the desmo due rules to see the background.
i was overtaken by geoff at the old hairpin near the end of the 2nd race and i was overtaken by the dls/dlc bikes at barn ... eg all within a short distance. geoff has a lot of local knowledge which i suspect the others haven't ... in qualification he was 0.6 secs a lap faster, at end of race 1 he was 7.12 secs clear (about 0.6 a lap faster) and at the end of the 2nd race he was only 3.35 secs clear which means a less than 0.3 sec a lap advantage ...i don't believe that's a power advantage .. that's local knowledge ... and what everyone seems to have forgotten ... rider ability (he is a v good rider who used to race against the baines's and beat them!) it all seems to me a great shame that everyone is concentrating on the hardwear issues and taking away from geoff what was a well earned and deserved win in both races.
for what it is worth i believe changing the rules so quickly as a knee jerk reaction would be wrong ... it's just too soon ... we need to see how it goes at the next race at the v least before looking at any changes...
riders also need to look at their riding and not their machines for the fact that they were slower than the bike infront ... alan johnson on a 583 came 5th and 6th. |
I have to agree with most of what Michael has said(there has to be a first time for everything mate  ) Both Neil and John Hackett, engine builders who KNOW about Ducati's have stated that a big bored 583 when set up properly with short manifolds and flat slides will MORE than live with a 620. In fact John's reasoning behind his initial development of a the '620' big bore kit was because he felt the 675's would have an advantage! Having watched all of the racing at the weekend I have to say that Geof Spencer was VERY smooth and fast everywhere I could see him, noticeably faster than most into and over the mountain-which is just race and track experience. Don't forget that Dave Riley riding a standard-eg not specially dynoed and set up-620 monster with only 1 disk- was leading race 2 for the first 2 laps-and he is a novice rider, and Andrew Johnson finished 5th on a 583!
John
[Edited on 3-5-2005 by Monty] |
Is it just me or does it seem to be just the people who have 620's or the rule setters who seem to be in denial about the 620's advantage?
I'm sorry Monty, but I think you've spent too long hanging around in the rarified atmosphere surrounding top engine builders like Neil Spalding and John Hackett.
I'm sure that it is possible to build a flat slide carbed 674 cc bike that is quicker than a 620. If you happen to have the budget and the renowned engine building skills of Mr Hackett or Mr Spalding to do it.
By the time you've done that it's going to cost you more money than it would've done to buy a 620 in the first place.
Meanwhile, back in the real world, guys who thought that the series was started as the antidote to 'cheque book racing' are spending untold hours in unheated lockups with a few spanners and a socket set doing everything themselves. The knowledge that John Hackett or Neil Spalding could build them a race winning engine is about as relevant to guys on a budget as walking to the moon and back. Fine in theory but it's never gonna happen.
These are the guys that I believe the race series was conceived around and I think the rules have stitched them up. They've spent thousands only to find that they are outclassed by people with bigger pockets. You only had to look at the 3-4 lengths that the 620's were putting on 674's along the very short start finish straight after being neck and neck at Barn to see the advantage they've got. It's clear from the stands, never mind the view from the saddle. The difference on circuits with longer straights is going to be huge.
Here's a thought. Instead of trying to level the series (albeit too late) with talk of how the 583/674 people should spend another thousand or so to get flat slides and some serious engine building done, how about asking John Hackett and Neil Spalding to work out the size of inlet restrictor that would be needed to restrict 620's or 680's to 52 bhp.
Shouldn't be hard for top engine builders to work out and would cost the 620/680 boys about £20