For some time Jerez, Spain has signified the beginning of the European leg of the MotoGP world championship and for 2004 the state of play remains the same, despite Jerez being the second round this time round rather than the third.

It's fitting then that Jerez is also the circuit which pulls in the largest crowd by far during the 16 round championship, well over 200,000 last year during the three day event. It's partly due to the Spanish passion for motorcycle racing, but also the circuit's reputation for providing hard and close racing surely has an influence on ticket sales too.

The closeness of the racing can be attributed to the undulating 4423m layout, numerous hard braking areas and countless camber changes; making a predictable chassis balance the primary concern - especially during heavy braking. For this reason it's necessary to maintain stability over the countless bumps that infest the entry into almost every turn, while also providing front-end feel which will inspire confidence.

The front forks will need to deal with the high braking loads yet they must also offer enough movement while almost fully compressed to ensure that it is the suspension absorbs these bumps rather than the front tyre. Increasing the spring rate will prevent the front of the motorcycle from diving too quickly under heavy deceleration - a result of the weight transferring forward - while the fork compression damping will be set to allow enough high-speed movement to deal with the repetitive bumps.

Fork rebound on the other hand is dialed in to slow the return of the forks to their full length. This will prevent under-steer as the rider makes the transition from brakes to throttle and the weight transfers to the rear of the motorcycle. These steps, along with reducing the rear ride-height, will ensure the back wheel stays planted on the tarmac, in turn improving braking stability.

Yamaha's latest generation Deltabox frame (featuring the new inverted swingarm) with reduced lateral flexibility will help increase the M1's feel mid turn. This is achieved without compromising the torsional rigidity - needed to ensure braking stability on such a challenging circuit. This in turn increases rider confidence to attack the corners harder, while still offering the ability to carry the high corner speeds necessary to achieve a fast lap.

The rear spring rate will be set slightly firmer to prevent the bike squatting under power through the high speed corners and the resulting cornering forces, while overall feel will be ensured with less compression damping - aimed at helping riders gain the best drive off the positive cambered turns.

The M1's new generation in-line four-cylinder engine will also help this cause thanks to its revised firing order offering a more progressive power delivery and predictable throttle response.

Pre-season IRTA tests have shown that in the hands of Gauloises Fortuna Yamaha rider Valentino Rossi the M1 is capable of setting the fastest time at Jerez, when required. Combined with Rossi's impressive result from the opening round there is an indication that the M1's revised chassis and engine package has made the Yamaha more useable in the latter stages of the race - a crucial advantage at Jerez.



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