ale ntino Rossi's sensational performances in
the MotoGP tests at Catalunya and Jerez
were not only due to his riding ability and his
skills as a development rider, but also to an
almost completely new motorcycle.
We were aware from the results of previous tests that
Rossi had selected one motor specification out of a choice
of four he had been given. Without a doubt, that engine is
quite different from the one that Yamaha used here last
year. It looks similar, but the noise is far more like the
Suzuki V-four than the inline screamer it had last year. A
close look at the motor shows a completely different cylinder head with , judging from the distance between the
cams, a very narrow valve angle.
What had not been seen before these tests though was
the Yamaha's new chassis. At the end of last year at the
Valencia meeting, Yamaha turned up with new chassis for
both Carlos Checa and Norick Abe. This chassis had its
front engine mounts moved down from the top of the
cylinder head to the top of the cylinder barrel , with long
spars connecting the mounting to the main chassis. The latest version has taken this a stage further, with spars now
connecting the main chassis to the top of the crankcase. It
looks quite flexible and unsupported, and this is clearly the
main objective. Motorcycles use chassis flex to let the ir
wheels follow bumps in the road when they are leaned
right over - a front fork tends not to work very well when
leaned over at 45 degrees or more. As horsepower levels
keep increasing in MotoGP.the chassis' ability to work well
and give the rider a confident feeling, especially at the front,
is increasingly important.
Yamaha's new design reflects both the RCV Honda and
V
24
APRIL 21,2004 •
CYCLE NEWS
