@Daniel: Hamilton's pole position was a 1:25.232 on medium tyres. Rosberg's time was on the softs and roughly 2.5s quicker.
@bb: I've never tried using one for that purpose
@mfbull: The compound you mean? Or the construction?
@mfbull: I'm not entirely sure about that, but essentially there is a chemical reaction as it heats up and that creates the grip. Heat them up too much and they overcook. There is a difference between wear and and degradation though. Wear is the physical loss of the tyre rubber as it gets left on the track or comes off in marbles, degradation is more down to the changing state of the compound.
@Patric: Renault has only brought its latest performance upgrades this week, so I think it's a bit early to be guessing. My understanding was that they were trying to cut the deficit from around 80bhp last year to 40bhp this year, but it's all guesswork at this stage.
@mfbull: Sometimes when the tyres cool down again the grip comes back, which is why you see them back off between hot laps. In races they often suffer from graining, when the rubber on the tyre surface rolls into little balls and reduces grip. However, they can sometimes come through those graining phases and get a clean surface once more, offering more grip.
@Chirag: The Sauber's time was more about the super-soft tyres than the engine, in my opinion. Interestingly, Ferrari is the only one of the three engine manufacturers from last year that has talked about saving tokens for later developments. Renault and Mercedes intend to spend big for the first race, so we might see Ferrari come stronger as the year progresses.
@mfbull: It's also about conditioning the tyre. Bringing it in so it continues to offer grip over time. A lot of that is down to the set-up and car's qualities, and to a lesser extent the driving style too.
Button hits 100 laps in the McLaren MP4-30 today. Before today the car had completed 209 laps over nine days. Looks like progress.
@MarieClaude: Thanks for the update. Makes sense as that's the day after the final day of testing.
Just as we start to praise McLaren, Button stops on track and causes a red flag.
@TheGhoul: My understanding is they can miss three races and still be eligible for prize money. So that would mean turning up in Bahrain. However, that's for the prize money and I believe their duty-bound to the FIA to turn up at every race.
@xxx: If the car is running smoothly they will start to look more intently at performance and set-up. But considering where they were a day ago, another three days like today will seem like a bonus.
It looks like the McLaren has stopped between Turns 7 and 8.
@V.L.Efranov: The team intends to make Australia. The big question is whether they will have two cars ready before they are due to be airfreighted on March 6 and whether they can build a car that is in "full compliance with the 2015 regulations", which is a proviso the FIA has released today. So that means crash testing a new 2015 nose and side and rear crash structures in time for the first race.
@TR: There is the 107% rule so if they are too slow they will not be allowed to qualify for the race. However, slow cars can be dealt with in motor racing - just look at WEC and the mix of LMP1, LMP2 and GT-Pro and GT-Am cars.