Pirelli's attempts to reintroduce the 'cliff' in the performance of tyres on offer to Formula One tyre have yet to convince Mercedes driver Lewis Hamilton.
The reigning world champion said that he hadn't noticed much change so far in terms of tyre performance, which is supposed to suffer a steep drop-off once it passes a certain amount of mileage in an effort to make racing more interesting.
"To be honest I was doing 20 lap stints and there wasn't much of a cliff," Hamilton said on Monday after his first day on track in the new car. "They were very similar to last year I would say. I don't know what more to say about it. It doesn't mean it's a good thing!
"There’s not much of a cliff to be honest," he confirmed after a second day of testing on the harder compound tyres later in the week. "It just feels like a harder tyre, it’s not giving me any more grip. I think I preferred last year’s.
"There is a little bit more deg maybe on the left-front tyre but generally it’s nothing exciting or nothing new that will make a difference. Nothing exciting there."
The changes that he did notice in the car's performance compared with how he ended the 2015 season came from more obvious sources of off-season development.
"The front wing is an improvement, which is good," he said. "It’s always about small increments and that’s what it’s brought."
There are also adjustments to the nose of the W07 for Hamilton to factor in to his assessment.
"Sometimes it’s transparent and most of the time it’s very much the same. Some have different characteristics, so when you begin to steer they behave differently and you have more or less downforce and sometimes you have more downforce in general.
"On the mechanical side of things the car is better - the packaging, the aero performance is stronger than it was last year, so it is an overall performance which obviously is the target.
"The engine feels exactly the same, Mercedes have built the best engine for some time and it feels incredibly powerful - it always had - and it honestly feels just as strong as last year. It's difficult to really pinpoint out a couple of brake horsepower if it is."
A closer look at the Mercedes W07
FEATURE: The first test in numbers
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