The Proton KR team will be racing its prototype four-stroke machines at the British Grand Prix, despite rider Jeremy McWilliams’ fears that the bike may not be up to scratch.

The Proton KR team will be racing its prototype four-stroke machines at the British Grand Prix, despite rider Jeremy McWilliams’ fears that the bike may not be up to scratch.

The team has battled with oil pressure problems, defective clutch components and gearbox maladies. McWilliams has only managed to finish in the points twice this season.

"Since we started at Le Mans, where we first rode the four-stroke bike, we haven't made the progress we expected we could," McWilliams says. “When you start out on something like this, of course you realise there are going to be difficulties along the way. But you try not to focus on that part, you try to focus on the possibilities of the bike and how it will develop.

"You think 'this could be good, this could be really good'. But we won't get there quickly because basically we're testing at the races. All the major factory teams developing four-strokes did their testing behind closed doors, they didn't put it straight out there on the track like we've done.”

But McWilliams says they have been working on the bike since the Dutch Grand Prix at the end of June. “We are getting the bike to perform better into the turns and we hope to find more power from the dyno and from testing. It’s hard because we have no information about four-stroke performance at any circuit and so every time we are starting from scratch. We knew it would be tough but we are all pretty upbeat going into the Donington weekend,” he says.

Yukio Kagayama will again replace Kenny Roberts Jr at Donington Park. Roberts has not yet recovered from chest injuries sustained just over one month ago at Mugello.

“Of course it’s disappointing that Kenny is not fit enough, but it is important that he regains full strength before coming back,” said team manager Garry Taylor.

“On the other hand, it’s another chance to work with Yukio, who we know well from past GP experiences. He always tries his hardest and is fun to have in the team, and he did a great job for us at Assen, where he was thrown in at the deep end.”