In keeping with a man who prefers to do his talking on the track, Kimi Raikkonen [Images] has said little about his Formula One title chances before next week's season-opener.

Apart from highlighting a problem with McLaren's Mercedes V8 engines at the end of January, the driver many see as this year's likely champion has steered clear of any bold predictions.

"We have had a productive couple of days in Valencia this week, we had some good pace with the car and I set the fastest time," the team quoted him as saying after Wednesday's final test before the March 12 Bahrain Grand Prix.

"But testing is very different to being on the race track.

"I am now looking forward to getting back behind the wheel in Bahrain next week and driving the car in a competitive environment to see where we really are performance-wise."

McLaren won 10 races in 2005, two more than champions Renault, and had what was widely considered the faster car for much of the season.

They should by rights be starting the new year as championship frontrunners.

Yet while their new MP4-21 looks the business, with a shining silvery chrome livery, there have been question marks about engine reliability that have allowed Renault, Honda and Ferrari [Images] to be seen in a stronger light.

ENGINE TROUBLE

"The biggest part of the problem is the engine," Raikkonen declared in January after trying out the car for the first time in Barcelona.

"They (Mercedes) are not where they should be and they need to improve. On the engine side we have a lot of work to do," added the 26-year-old, whose future is up in the air after McLaren's decision to sign Renault's world champion Fernando Alonso [Images] for 2007.

Mercedes motorsport head Norbert Haug confirmed there were difficulties, telling Britain's Autosport magazine last month: "I openly admit that we are not where we want to be with the V8 programme.

"The time scale is tight and we have some problems. Will we have it 100 percent solved before Bahrain? Who knows?"

However the latest version of the engine has looked considerably stronger in final tests, prompting Alonso to warn that the former champions were back in the reckoning.

That will be good news for Raikkonen, runner-up to Alonso last season despite winning as many races as his rival, who is justifiably nervous about reliability.

In the last four years, he has twice finished second in the championship and can point the finger at mechanical failures for costing him wins and the crown.

Persistently linked to a move to Ferrari for 2007, Raikkonen's future at McLaren could depend on how competitive his car is in the races before he has to make a definite decision.

That will mean making a better start than last year, when Australia kicked off the season.

McLaren were favourites then but a wet qualifying session knocked them sideways and Renault's Giancarlo Fisichella ran way with the race.

"The whole team, including the drivers, psychologically over-reacted to the first grand prix and the qualifying," recalled team boss Ron Dennis.

"We were pumped up, we believed in ourselves and then halfway through practice it rained...we didn't respond well to it, the drivers didn't respond well, the team didn't respond well," he added.

"Both drivers got frustrated, ran wide on corners and damaged the cars...that was a catastrophic race for us but more importantly it really knocked us psychologically."

Reliability, with Raikkonen taking several hits in qualifying after unscheduled engine changes cost him 10 places on the starting grid, reared its head later.

Bahrain, despite the danger of occasional desert storms, should at least be dry next week. How Raikkonen's car stacks up to Alonso's remains to be seen.

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