MotoGP Setup report - Sepang

Circuit: Sepang
Country: Malaysia
Track length: 5548 m
Opened: 1999
Fastest Lap Ever: 2' 1.833 (Valentino Rossi, 2004)
MotoGP lap record: 2' 3.253 (Valentino Rossi, 2004)
Last year MotoGP winner: Valentino Rossi
Circuit web site: http://www.malaysiangp.com.my

2004 race summary

Valentino Rossi arrived in Sepang in very determined mood, wanting to forget
about his Qatar DNF. Aided by the extensive preseason tests on the Malaysian
circuit the YZR-M1 was in very good shape to give Rossi the performance he
needed to get his revenge. He dominated qualifying, setting the fastest lap
ever, and come Sunday he slipped straight into second place on the first lap
behind Alex Barros (Honda).

The two switched places several times until Rossi made his final pass stick on
lap four. Eventual second place finisher Max Biaggi (Honda) was close behind
determined to stay in contention for the top podium position. Rossi managed to
maintain and extend his advantage, while he was cautious not to ruin his tyres
with air temperatures being higher than expected, hitting 40°C.

Still he was able to still put in laps inside the 2'03s, setting a new lap
record of 2'03.253 on lap eight. Rossi eventually finished 3.6 seconds ahead of
Biaggi, who never quite made it to pose a serious threat. Colin Edwards had a
disappointing result on his Honda finishing in 11th place.

Set-up report YZR-M1

Due to the Sepang circuit's hairpins and numerous hard braking areas a fast lap
comes down to braking stability and the bike's turn-in characteristics. Two such
areas include the combination of long straights and hairpins that make up the
final sequence of the 5542m layout. Suspension technicians have a relatively
easy task with the track surface boasting a high level of grip and few bumps. At
the same time it is a venue that also offers challenging high-speed sweepers -
the first, diving down deep into a hollow before climbing back out the other
side for a 90 degree right-hander. This corner alone has a tendency to load up
the front of the bike to the extreme on the entry, and the rear on the exit. The
other is a blind left-hander that disappears over an undulating crest, which
ensures that keeping the back-end in line will be challenging even for the best
MotoGP talent.

Therefore the ideal chassis set-up is somewhat compromised. With this approach
the key areas of concern are catered for - such as braking stability and chassis
agility under heavy loads. To help cater for both the suspension balance will be
targeted towards a similar neutral feel as that used in Motegi. The front fork
springs will be set slightly firmer - achieved with a higher spring rate - with
the bike's attitude controlled by the spring preload. Softer damper settings
will improve feel, leaving the heavier springs to deal with the high cornering
and braking forces. As for the rear shock, it will also carry a high spring
rate, but the damping will still be smooth to give the riders the feel needed to
get the power down hard and predictably, in conditions that can melt a rear tyre
in a matter of laps.

Aiding the Yamaha contingent at Malaysia will be the 2005 YZR-M1's in-line,
four-cylinder power plant. This year's evolutions in terms of electronic engine
management will give improved throttle linearity making the power delivery more
predictable. The more tractable power will also improve tyre endurance, a must
in the hot Sepang climate.