Biaggi and Checa make progress in Portugal.

Marlboro Yamaha Team riders Carlos Checa and Max Biaggi stayed on at Estoril yesterday to prepare for the final five races of the 2001 world championship.

After a somewhat difficult Portuguese GP, in which Checa took fourth and Biaggi fifth after a minor tumble, the team focused on evaluating new parts and settings. Both men lapped fractionally faster than they'd managed in the race, allowing them to leave the track feeling confident about the forthcoming Valencia Grand Prix on 23 September.

"Our job is always to make the riders feel more confident, so they can ride faster, and I'm confident we've managed that today," smiled Marlboro Yamaha team director Hiroya Atsumi, "Both our riders went well during qualifying at Estoril, but then Carlos had a few minor problems in the race and Max crashed, so we had a frustrating day.

"Today we tried some new engine and chassis parts, plus some new 16.5in tyres from Michelin, and we also worked at continuing to improve the balance of both riders' bikes. This track and Valencia are quite similar in terms of machine settings, so we should be in good shape for the next race. But we also wanted to try some things for the first two 'flyaway' races at Motegi and Phillip Island, because they're very different tracks."

Checa, who came through from eighth to fourth in the Estoril race, was happy with his day's work.

"I didn't expect to make all the improvements we made today," he said, "We fixed the little chatter problem we had yesterday, and I was able to keep a good pace on used tyres, which is very important. I'm looking forward to Valencia, especially since I had terrible results at the other two races in Spain earlier this year. I really want to fight to win, and I will focus 100 per cent on being the best."

"Carlos had a bit of rear-end chatter in the race here, and he wasn't totally happy with the balance of the bike on corner entries, so we've been working on that," chief engineer Mike Webb added, "Ninety per cent of our work has been on detail chassis settings, and that will be applicable to Valencia, so we're pretty happy."

Biaggi and his crew also worked hard on set-up, with the aim of putting two disappointing weekends behind them and bouncing back at Valencia.

"Now I want to win as many more races as I can this year, I want to keep pushing until the end," the Italian said, "We tried some different chassis settings today, which gave me a little more confidence. They were small improvements, and they made the bike better in some areas."

Biaggi and his chief engineer Fiorenzo Fanali also used the day to make a detailed analysis of data from Sunday's crash.

"We've examined the data very carefully and we can confirm that Max did nothing wrong, he was riding through that corner at the usual speed," Fanali revealed, "These tests have given us a good start for Valencia. Of course, Max was disappointed with his race result here, but he'll be strong at Valencia and ready to try to win again."

The Marlboro Valencia Grand Prix is round twelve of this year's 16-race 500cc world championship, and the last race in Europe before three 'flyaway' GPs during October - in Japan, Australia and Malaysia. The curtain then comes down on the last ever 500cc world championship in Rio de Janeiro on Saturday 3 November.

Lap times - Estoril (10 September):

Carlos Checa Marlboro Yamaha 1min 40.75secsMax Biaggi Marlboro Yamaha 1min 41.10secs