Ducati & MGP

If you get this rag, the article is written by Kevin Cameron called "Tales
of the Testastretta".

Basically Ducati ran up against a RPM limit of 12,200RPM due to excessive
valve train vibration /resonance at this speed on their 996. At that time
they'd apparently been using ball & roller bearings somewhere up top and
the result was a lack of stiffness that was fixed by going to plain
bearings and tightening clearances. Anyway this is plolly the main reason
that those big twins are relatively competitive on a one up basis with 4's
in WSB.

Theoretically twins can never match 4-cylinder high RPM performance and 4's
can never match the low RPM twin performance. This is due to VE=high
velocity flow, area rule & size/weight in their perspective valve train vs.
piston sizes but apparently Ducati has come closer to a theoretical max for
a big valve engine than anyone else due to optimizing their desmodromic
valve trains. However, torque curves don't lie and they still start to lose
steam up top compared to the four cylinder bikes that are running up to 18K
RPM with valve spring technology as are the V4 Ducati's when they're scaled
down to the size of the rest of the fours. Actually I believe some of the
MGP 800cc mfgs are using pneumatic valve actuation now.

Someone suggested that Ducati made better MGP frames but watching the races
during this year, the Ducati's seemed to have more power down the straights
(kind of like Spies & Maladdin running away from the fact in AMS SB), so I
think the Ducati fours were making considerably more power than the rest,
else Rossi and the boys would have had a better chance keeping up. It's
been clearly a technical cue this year for Ducati & company & not
necessarily just better riding, like back when Rossi switched to riding for
Yamaha instead of the superior HP V5 of Honda.

If you don't like technically related stuff (which many of you don't in AMS)
then skip this one ...No one's posted a new thread since Sunday, I believe,
so consider this filler for a news group hell bound of sub thread jacking
(mostly OT political or gory in nature).

Bob Nixon.

--
Bob Nixon, RZ-350, Chandler, AZ.

On Oct 17, 1:36 pm, _Bob_Nixon_ <bi... RemoveThis @nospam.com> wrote:

> Someone suggested that Ducati made better MGP frames but watching the races
> during this year, the Ducati's seemed to have more power down the straights
> (kind of like Spies & Maladdin running away from the fact in AMS SB), so I
> think the Ducati fours were making considerably more power than the rest,
> else Rossi and the boys would have had a better chance keeping up. It's
> been clearly a technical cue this year for Ducati & company & not
> necessarily just better riding, like back when Rossi switched to riding for
> Yamaha instead of the superior HP V5 of Honda.

I don't know where someone suggested that Ducati is making better
MotoGP frames than other manufacturers, but I don't see any evidence
of that. There has been ample evidence this year that the 800cc
Desmosedici bike has a horsepower advantage over all of its MotoGp
rivals. Whether in corner exit speed or top speed at the end of long
straights, the Ducatis have been faster all year. I don't think
anyone disputes that. At least, I haven't heard anyone disputing it
on the race TV coverage, in the print media, or even here, where
EVERYTHING is disputed.

The other huge difference this year has been the Michelin vs
Bridgestone tires. There is talk of MotoGP going to a spec tire next
year, much as Formula One has done. Personally, I'm in favor of
that. What do you think?

Tim