Roberts goes back to the front.

Kenny Roberts, the defending World Champion, put himself back with the front men on the first day of practice for Sunday's South African Grand Prix, claiming fourth-fastest time and a place on the front row of the provisional starting grid after a "drastic improvement" since the opening round in Japan two weeks ago.

"After Suzuka, Warren Willing, my crew chief Bob Toomey and I had a discussion on how to improve our situation," explained Roberts. "We came up with some changes that have made a drastic improvement in the way the bike comes out of the corners, though the balance could be a bit better."

"We were looking for something not so much for lap time, but that that would work over race distance, and be easier on the tyres. There are still some tiny things we need to do, but I am sure that Bob and Warren know how to fix them. We have the same motorcycle as Suzuka but a different approach. We have struggled at this track, but now the bike is the best it's ever been here. The most important thing is that the bike is responding in ways it couldn't respond at Suzuka."

"You solve one problem and that creates another," added Technical Adviser Warren Willing. "We made a rear geometry change after the last race to try and improve the feel of the bike over race distance. That seems to have been successful, but now we have to get the bike balanced again with the new settings. The track surface is better than it was in previous years and we were already matching last year's Friday times in the first hour. In previous years, we've had tyre choice problems. So far, tyres don't seem to be a problem this year."

Team-mate Sete Gibernau - a former pole qualifier at the twisty circuit - ended up 13th fastest, but optimistic of more to come in tomorrow's final qualifying session.

"We've made some pretty big changes to the bike - to how it reacts," said Gibernau. "There are some good points, but it seems there are always small things stopping us taking that step that we need so that I can feel comfortable on the bike and ride it to my maximum. Today I was wrestling the bike, even on the straight, and that's not right.

"We have almost the same settings as Kenny, and my crew is working real hard - we are making progress, but little things keep happening to make our life difficult. This is an important race for me - I like the track, and I know how to go around it quickly. But I am still getting used to the Suzuki. I hope that tomorrow we can get rid of the problems and move forward on the grid for the race."