Ducati has won 22 WSBK titles and 1 MotoGp title employing the 90º V engine
configuration so I don't see why Filippo Preziosi would think change... fact is
since 2002 the M1 has changed the most to keep up the Vs so Yamaha's
engineers are the ones that may think about switching to a V4 in 2012...
First change was Yamaha's cross plane crank which was designed to mimic
the good points of linear V5 secondly was a weight shift to mimic the weight
distrubution of the Ducati to help utilize the performance of Bridgestone...
Yamaha's I4 is short but it don't matter to the engineer because it's center of
gravity currently rest 30mm further back in the frame thanks to spec tire
Quote MCN 2009:
"Arguably the biggest change for Rossi's bike, though, is a much
shorter wheelbase to help utilize the performance of Bridgestone's
tires. Rossi's bike is now 40mm shorter than the MI he raced to fifth
place on his Bridgestone debut back in March in Qatar. And he said
drastic reduction was essential to help keep Yamaha ahead of Ducati
Quote Rossi 2009:
"The new bike is different in the chassis," Rossi explained. "The
weight distribution is different and the feeling is not so bad. We
have a little bit more stability with the front and rear. We
discovered during the year that Bridgestone needs a completely
different setting compared to Michelin. We knew this quite early in
the season, but we realized we needed to move the weight of the bike.
"So we had to shorten the bike to use the tire in a different way,"
said Rossi, who conceded the much shorter wheelbase did mean
sacrifices in other areas."
"For sure, a shorter bike is a more difficult bike," he admitted. "You
have more wheelies and it becomes more unstable, particularly in the
faster corners, so you need a rider that is able to manage this. I
have to change my style to adapt to the bike, because it is quite
different compared to last year, but if you can use the potential of
the Bridgestone tires then it is possible to go very fast. That is why
we need to have made such big changes for the chassis next year."
Quote Julian Ryder:
"When Rossi defected from Michelin at the end of 2007, he
immediately wanted to know what spec Bridgestone tires Stoner used.
Whatever they were, Rossi knew that he would have to adapt himself and
his motorcycle to those same tires if he were to have a chance of
defeating the youngster."
"Stoner uses a stiffer front that most Bridgestone riders, a tire that
doesn't necessarily offer a better lap time but does deliver a better
race time, because its stiffer, less forgiving construction provides
better race long support/perfromance. Rossi knew he had to use this
front, even if it as tricky as hell to master. This tire requires a
rare combination of aggression and deft control to work effectively,
and also needs a certain amount of pressure applied during corner
entry to make the rubber squirm into the correctly shaped contact
"Thus Rossi's crew adapted his M1's set-up to apply the
correct load to the front tire, and then Rossi had to revise his
cornering technique to suit Bridgestones, using smooth, sweeping
Quote Rossi: "The Bridgestone tires have a different construction and
differenct charactor, so I need to ride different lines. If I use the
same line I used with Michelin, I lose time."
"The 800 require a neater, more classical and less thrilling
to watch arcing line, which perfectly fits the Bridgestones.
Quote Rossi: "With the 800s, everything becomes more flat" adds Rossi
explaining that his M1 features less dive into turns and less squat on
the way out. "Now corner speed is the most important issue for lap
time. Before it was about braking and accelleration, so you had two
very different parts to the corner, clearly divided, and you needed to
move on the bike in a different way. Now it is corner speed, so the
braking and accellration become a little less important"
But when he tried the harder front he couldn't get on
with it. because it was too stiff for him, so ne couldn't get any feel
- and without feel, even the best "front tyre in the world is totally
Quote Neil Spalding:
"Rossi won the 2008 MotoGP championship with a bodge - a bike
built for Michelins that he and his crew chief Jeremy Burgess then
persuaded to perform on Bridgestones, ultimately beating the
Ducati on which those same tyres were initially developed.
It was an amazing achievement, not only because Rossi had to
change his riding style to pull it off, but because he and his team
only needed three races in 2008 to figure out the problem. It turned
out that the Ducati-developed Bridgestones liked a whole lot of
weight on the rear, and not much on the front. In converting the
Yamaha to suit this new reality, the team first they used up all the
standard chassis adjustment, then ordered a whole new chassis
from the factory. It can't have felt good to Valentino, who up to then
had spent 12 years in GPs riding traditional front-heavy bikes, but it
was a case of adapt or lose."