The chase for the Motor Cycle News British Superbike crown hots up this weekend (10-11 August) as Britain's premier motorcycle Championship powers into Thruxton.

With just eleven points separating the leading duo of Steve Hislop and Sean Emmett the series steps up a gear on the UK's fastest circuit for round nine of the Championship.

This weekend, the title fight takes on a new twist. Emmett has switched teams, leaving IFC Ducati, who have withdrawn from this event, to ride a Virgin Mobile Aiwa Yamaha R1.

The decision of IFC to pull out of the ninth round is brought about by ''the extended delay of the planned sponsorship budget.'' Emmett has moved swiftly to secure a competitive ride under the Colin Appleyard banner, riding for Rob McElnea. As he tested the powerful R1 machine at Cadwell Park earlier in the week Emmett commented: ''It feels every bit as good as it looks - the test went well and I am really pleased. I think the bike will be well suited to Thruxton and I'm confident that I can be up there at the front.''

The Weybridge-based rider knows that he faces a tough challenge. Hislop has won five races so far this season, but after his early season dominance the Flying Scot has encountered a case of second-quarter blues which has seen Hizzy challenged by four other riders including the reigning Champion John Reynolds.

Emmett, who last year played a strong supporting role to his then team-mate Reynolds, claimed victory in the first race of the season and went on to chalk up a winning double at Snetterton. Apart from a technical problem in the first of the two races at Brands Hatch, the title chaser has been a top three finisher ever since.

This excellent run of form and a sheer enjoyment of riding has put Emmett in his best ever position to win the title but he can take nothing for granted aboard his new machine. Not only has Hislop found his form once again, but Michael Rutter is producing outstanding shows aboard the Highland Spring-backed Renegade Ducati.

Meanwhile, Series leader Hislop is raring to go. Fully recovered from the collarbone he broke in the previous round and determined to extend his lead at the Hampshire circuit, where he rode his MonsterMob Ducati to victory in the first of the two races last year. Third place Rutter has tasted the winner's Champagne four times this season, including a double at Rockingham, but is still kicking himself for his last lap, last corner tangle with Hislop at Knockhill - he has apologised profusely and knows that it cost him dearly.

The Leicestershire-based rider can ill afford any more errors if he is to head off the leading duo this weekend and concentrate on the task ahead. But at the same time he will need to keep a check over his shoulder, as fourth place Reynolds is keen to repeat his victory of last year, a must if he is to retain a realistic claim to back-to-back Championship glory.

After missing four races the Championship welcomes back Rizla Suzuki rider Karl Harris, who returns from injury while the Virgin Mobile Aiwa Yamaha pairing of Steve Plater and Simon Crafar will be looking to take maiden wins for the season.

The action however is not confined to the headline series. A comprehensive support package also has its fair share of stars and excitement. Nine-time Isle of Man TT winner Dave Jefferies chases a fifth victory in the Performance Bikes Superstock Championship to keep ahead of Chris Burns in the title race while young Scottish rider Stuart Easton heads the action in the Supersport Championship ahead of Scott Smart.

Adding to the weekend's activities is the 125cc National race, with Chris Martin bidding for a fourth victory to move further clear of Christian Elkin. Craig Jones and Thomas Sykes continue their scrap for supremacy in the Dunlop Junior Superstock series while the third round of the Ducati S4 Monster Challenge rounds off the racing.