The Grand Prix circus says goodbye to Europe this weekend, almost five months after the Continental Grand Prix season got under way at Jerez back in May. The end of GP racing's European tour of duty also signals the beginning of the end of the 2001 World Championship, with just four out-of-Europe events remaining after Sunday's Marlboro Valencia Grand Prix.

The last third of the campaign spells extra pressure for every rider in the premier 500 class, and none more so than Marlboro Yamaha Team star Max Biaggi, currently chasing Valentino Rossi (Honda) for the last-ever 500 crown. The Italian has impressive end-of-season form on his side (he was the most successful rider in the closing stages of both the 1999 and 2000 series) but he's now a long way behind Rossi after two falls at the last two events consigned him to tenth- and fifth-place finishes.

Valencia could be good for Biaggi, however, for this is where the wheels came off Rossi's title challenge last September, when the Honda rider tumbled out of the race uninjured. The Spanish track is renowned for producing close and hectic racing, something relished by both Biaggi and Marlboro Yamaha Team-mate Carlos Checa. Indeed last year's Valencia GP produced one of the closest 500 grids in history, with just 0.982 seconds covering the quickest 16 riders.

Checa had a good run in Portugal two weeks ago, coming through from a so-so start to take fourth, just one place off the podium. The Spaniard has already scored two podium finishes this year, in France and Germany, and there's nothing he would like more than to score a top result in front of his devoted home fans.

After Sunday's racing the GP circus packs its flight cases and heads east for October's gruelling run of back-to-back races in Japan (for the Pacific GP), Australia and Malaysia. The 2001 season concludes with the Rio GP on Saturday November 3.

Motorcycle racing can be the toughest of sports, just ask Max Biaggi! The Marlboro Yamaha Team man has had a magnificent 2001 season, scoring three wins and challenging Valentino Rossi (Honda) for the last-ever 500 World Championship, but the last two races have not been kind to him.

There's no doubt that Biaggi is super quick at the moment - he has started the last four GPs from pole position - but tumbles at the Czech and Portuguese GPs have left him a long way behind Rossi with five races remaining. Going into August's Czech Grand Prix he trailed Rossi by just ten points, having closed the gap from 46 points. But he slid out of the lead at Brno, bravely remounting to salvage a tenth-place finish. Then he fell again at Estoril two weeks ago, while going for third, remounting to finish a spirited fifth. Unhurt in the two tumbles, he comes to Valencia determined to win again.

"Winning the title from here won't be easy, to say the least," says Biaggi. "But all I can do is stay focused on my job, which is the same as ever, to win races. Maybe we can't catch Rossi but my aim is to finish the season as successfully as I can, I want to keep pushing until the end. We tested a few things at Estoril the day after the Portuguese GP and I spoke to the engineers from Yamaha there to see if there is any more we can do to the bike to help me for the final races."

Biaggi had a great weekend at Valencia 2000, qualifying second, just 0.058 seconds behind eventual World Champion Kenny Roberts (Suzuki). He then led the race, finishing third. "I like the track, it's tight for a 500 but fun if you ride it right," he adds. "Probably the best thing is the special layout, it's almost like a stadium, the crowd have a great view of the action and you can hear them cheering all the way around the lap. It's like surround sound!"

Although he lags 43 points behind Rossi, Biaggi and his team refuse to admit defeat until the title is fully out of reach. "The last two races have been disappointing and frustrating for Max and the whole team," admits Marlboro Yamaha Team manager Geoff Crust. "But racing is sometimes like that, you have to soldier on. If you can't take a few bad days, you shouldn't be in this sport. We will fight back with the attitude that tomorrow is always another day, that's the way we have to look at it. Yamaha are working in Japan to try and find a little extra for Max. And although 43 points is a big difference at this stage in the championship, bike racing is the most unpredictable of sports. Anything can happen, and usually does!

"The thing is that everything has changed this year, the races are so much faster that you just don't know what's going to happen. Estoril was 42 seconds quicker than last year, Welkom 35 seconds, Suzuka 15 seconds, Jerez 23, Le Mans 16 and Brno 32. Those are huge improvements, so it's impossible to predict a race."

Carlos Checa has been building excellent momentum at the past few races and this weekend he goes racing in Spain for the last time this year, hopeful of a great result. Spain currently hosts three World Championship rounds each season and Checa didn't fare so well during his previous home-tarmac outings at Jerez in May and Catalunya in June.

But he comes to Valencia full of optimism after some great performances, including second in Germany and fourth in Portugal. Further tests at Estoril, following the Portuguese GP, put him in excellent shape for Sunday's 12th round of the 2001 500 World Championship.

"I feel I'm riding at a good level at the moment and we made a lot improvements during the tests," says Checa. "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. I really want to fight to win and I will focus 100 per cent on being the best. We've done a lot of work improving our bikes over the past few months. Racing is so competitive at the moment that the tiniest adjustment can make a big difference to your results. My main concern is perfecting the balance of the bike, taking a little more weight off the rear so the bike is more loose on corner exits, that's the way I like it. At Valencia the important thing is to get the bike working into the turns, so the front tyre can ride the bumps without losing grip."

During last week's Estoril tests Checa worked with crew chief Mike Webb towards a set-up that should be ideal for Valencia's numerous tight turns. "When we test straight after a GP the normal thing we do is address any problems we had in the race," says Webb. "Carlos may say 'These are the reasons I didn't go faster,' and we'll attack those things with a few ideas. We had a few parts to test at Estoril, concentrating on chassis items, some set-up stuff and some new rears from Michelin, a style of tyre that we plan to use at Valencia. Carlos definitely feels better after Estoril, he goes to Valencia in a happy mood. Whenever we've raced or tested there he's always been right on it."

Last September at Valencia Checa was indeed right on it. He was in the hunt for a front-row start, eventually qualifying on row two, just 0.319 seconds off pole. On race day he was running near the front and heading for a top-three finish until he overdid it on a tricky corner entry, only saving a tumble by running off the track. He rejoined the race to finish seventh.

Following a troubled start to the 2001 season, when an off-track injury forced him to miss the South African GP, Checa has been working himself up the World Championship table. He currently holds eighth place overall, though only two points behind Alex Criville (Honda) and just 11 points behind Norick Abe (Yamaha). Good results at Valencia and the final four 'flyway' GPs could move the affable Spaniard even further up the world order.

Valencia is the second-slowest circuit in GP racing with an average lap speed of just 150kmh, marginally faster than Estoril, venue for the previous GP in Portugal. This weekend Valencia hosts its third Grand Prix after featuring on the World Championship calendar for the first time in 1999. The circuit is one of several recently created in Spain, where motorcycling racing is the nation's second most popular sport, after football.

Most of Valencia's corners are slow and grouped closely together, a feature that affords spectators a mostly unobstructed view of the entire layout - a real rarity in the world of motorsport. It's an immensely physical circuit with riders afforded little rest between bouts of heavy acceleration, braking and cornering. The relatively short straight requires machines to run low gearing, which makes a 190 horsepower 500 particularly difficult to control, with riders battling wheelies and wheelspin every time they get on the gas.

The venue is officially christened the Ricardo Tormo circuit, in honour of the late Spanish rider who won the 50cc World Championship in 1978.

Max Biaggi and his chief engineer Fiorenzo Fanali have been working hard to understand Biaggi's tumbles at the last two GPs. "We've been examining the data very carefully," says Fanali. "But they were strange crashes - his speed was the same as before and the suspension wasn't doing anything different. Anyway, we'll try to give Max a better bike this weekend. We were lacking some acceleration at Estoril, though horsepower is less of a concern at Valencia. The important factor at this track is ease of handling - there are so many corners and so much turning. We're looking forward to it - we tested new engine and chassis parts at Estoril, plus some new tyres, so we hope we can win again."

Third at Valencia last year, Biaggi is well accustomed to the intricacies of this tight and twisting circuit. "Last year I remember that we worked hard in practice to get the front to ride the bumps without compromising grip," he says. "You need a bike set-up that's easy on the tyres."

Two weeks after contending with Estoril, the slowest track in World Championship racing, Carlos Checa & Co tackle Valencia, the second-slowest GP circuit. "Valencia is a lot like two thirds of the Estoril track," says Checa's crew chief Mike Webb. "There's so many corners, so the bike is on its side for a long, long time. That's why you need a machine that can turn well in any situation - whether you're entering a corner on the brakes or exiting a corner while hard on the gas. It's not the kind of place that needs a special set-up; some tracks demand something particular but Valencia isn't really one of them. Also, the grip level isn't a problem, so we're very optimistic that Carlos should have a happy weekend."

Checa adds: "Valencia isn't so fast but I like it, you can have some fun there. Qualifying will be particularly important because the times are always so close and you need a good grid position because it's a super tight and technical circuit, which means that passing is very difficult."