Barros fastest as rain arrives.

Alex Barros has set the fastest time on the opening day of the French Grand Prix at Le Mans, the Brazilian sitting slightly ahead of fellow Honda rider Sete Gibernau after 22-minutes of the second free practice session... at which point the much predicted rain finally arrived.

The opening minutes of the hour saw Shane Byrne's new spec KTM V4 engine cut out, leaving the Brit to abandon his machine (he would fail to complete a fast lap this afternoo), while Suzuki team-mates Kenny Roberts and John Hopkins held the early top two positions.

But by the close of the opening quarter Estoril winner Barros was on top of the timesheets, the Camel Honda rider just 0.015secs in front of Gibernau, with Max Biaggi, Shinya Nakano, Marco Melandri and Hopkins completing the top six.

The arrival of rain was signalled eight-minutes later in spectacular fashion, with Ruben Xaus sliding at considerable speed from his Fortuna Yamaha, while all around the circuit riders began slowing and then peeling into the pitlane... except Valentino Rossi, who chose to do one more lap to try and gauge the amount of grip should rain interrupt a dry race on Sunday.

But by the halfway point of the session all but Blata WCM's James Ellison were watching the rain from the pits, with Barros having extended his advantage over Gibernau to a still slim 0.119secs before the wet weather arrived, while Biaggi sat a further 0.328secs behind for an all Honda Friday top three.

Morning pace setter Colin Edwards was again the top Yamaha, in fourth, but one of on only four riders not to better his FP1 pace this afternoon (although he was still fourth overall on combined Friday times).

Gauloises Yamaha team-mate Rossi also lapped slower this afternoon, and was way down in 13th as a result; the world champion's best lap almost 1.5secs from Barros. However, on combined Friday times, Rossi was fifth fastest courtesy of his morning pace. The other non-improvers were Franco Battaini (18th overall) and Byrne (20th overall).

With 20-minutes remaining the rain ceased and soon after the majority of the MotoGP field returned to the track, but semi-wet conditions and a wet set-up meant that the dry times couldn't be threatened - lap times being around 12secs below the previous pace.

More rain is expected at the circuit tomorrow, and Le Mans could well see the first wet qualifying session of the season as a result.

Full times to follow...

Leading free practice times (2):

1. Barros
2. Gibernau
3. Biaggi
4. Edwards
5. Nakano
6. Melandri
7. Hopkins
8. Checa
9. Hayden
10. Capirossi
11. Roberts
12. Elias
13. Rossi
14. Bayliss
15. Jacque
16. Xaus
17. Rolfo
18. Ellison