Preview - Donington Park.

Shane Byrne holds a 44 point lead in the Bennetts British Superbike Championship heading into round four at the Donington Park grand prix circuit on Spring Bank Holiday Monday 26 May.

But it was only today (Friday) that Shakey and Airwaves Ducati team-mate Leon Camier were confirmed as racing at the event.

Earlier this week it was announced that: "After carrying out a detailed review of the performance of the twin cylinder and four cylinder machines over the first three 2008 BSB events, MCRCB consider the twin cylinder machines have enjoyed a competitive advantage and has authorised the modification of the minimum 165kg weight limit regulation for both twin and four cylinder machines by applying an increased new minimum weight limit of 175kg for twin cylinder 1200cc motorcycles."

GSE racing, which runs the Airwaves team, reacted furiously to the news and threatened to withdraw from Donington on the grounds of safety - since it hasn't had chance to test the bike at its new minimum weight. The North West 200 team, which runs Michael Rutter on a 1098 in the BSB class, supported GSE's position and said a final decision on whether to race would only be made on Sunday.

However, a subsequent rule amendment issued late on Thursday revealed that - following communication with Ducati Corse, which said testing was needed before such an increase - the 1098 weight limit will only be raised by 5 kg this weekend, with the exception of qualifying. As the average post-race 1098 weight this year has been just over 170 kg, no further weight should be needed.

But it may take more than a little extra weight to slow Byrne down, the former champion has won four of the six races, finishing second in the other two and - speaking before his attendance was thrown into doubt by the rule change - was aiming to make amends for missing out on the double last time out at Brands Hatch.

"I really wanted to bring the team another another double [at Brands], we had the pace, but it wasn't to be. We secured some good championship points though and I will come back even stronger at Donington," said Shakey.

HM Plant Honda's Cal Crutchlow is second in the points heading in to Donington, and therefore the man most likely to benefit from an Airwaves no-show. The Coventry rider powered through the pain barrier of a dislocated right ankle and ruptured ligaments to take his second victory of the season at the Kent circuit.

"I am here to race and to win races," said Crutchlow who was the British Supersport title holder in 2006 and who is determined to add to his collection of silverware this time around aboard the Fireblade.

His team-mate, local race-ace Leon Haslam, is hoping to use his home circuit to good effect as he plays catch-up in the title stakes. He knows that nothing less than an action replay of his winning double of last season will suffice is he is put his challenge firmly back on track.

The Derbyshire rider is currently sixth in the standings, adrift of Camier and former Superbike Cup winner and MotoGP rider James Ellison who is impressing aboard the Hydrex Bike Animal Honda.

Rutter won the first of the modern era Superbike races at the circuit back in 1995 on a Ducati, and now back with that marque in North West 200 colours is riding strongly alongside Relentless Suzuki's Michael Laverty, Tom Sykes on the Rizla Suzuki and Stuart Easton riding MSS Discovery Kawasaki.

John Laverty, riding the Buildbase NW200 Ducati looks all set to continue his domination of the Daily Star Cup - Laverty's bike is not affected by the rule change and so his weekend will go ahead as planned.

Around the two Superbike races, there is action in the Fuchs-Silkolene British Supersport Championship, which has produced three winners in as many rounds: Steve Brogan riding HM Plant Honda; Hudson Kennaugh on the Raceways Yamaha and Glen Richards on a MAP Embassy Triumph.

But adding considerable spice to that will be world championship contenders Andrew Pitt and Jonathan Rea aboard the Hannspree Hondas and Craig Jones on the Parkalgar Honda.

Steve Brogan and Derby's Jon Kirkham will continue their duel for the Metzeler Superstock 1000 title, with Kirkham also expected to star in the Henderson Yamaha R1 Cup. Add to that action from the Relentless British 125GP Championship, the KTM SuperDuke Battle and the Metzeler National Superstock 600 Championship and there is full sporting programme.

And, on Bank Holiday Sunday, immediately following the grid deciding session for the Superbikes there is the British round of the World Sidecar Championship in which Tim Reeves and Patrick Farrance need victory to speed their way towards retention of the title.