Nico Rosberg says the brakes "are really on edge" after suffering a fire during practice for the Mexican Grand Prix.
During FP1, Rosberg ran wide at Turn 12 trying to overtake Sebastian Vettel and rejoined the circuit with his rear brakes on fire. After a spell in the pits, Rosberg was able to rejoin late in the session and went on to set the fastest time of FP2 in the afternoon.
Rosberg says teams are always trying to push the limits with their brake cooling but admits Mexico is proving a bigger test due to the altitude.
"It is a challenge, we are really on the edge here on the brakes," Rosberg said. "If you cool the brakes more you lose performance because you need to open up the car and you lose downforce, so you go slower.
"You always want to be on the edge and here specifically is quite difficult because we are quite high up – it is like a ski station in Europe! The air is very thin so it doesn’t flow very well through the car and down the straights there is no resistance. We had the Monaco rear wing on the car with full downforce but we are doing Monza speeds, so it is quite impressive."
While encountering issues during the day, Rosberg had time to form a positive opinion of the Mexico City circuit's layout.
"It is unique, very slippery because the asphalt is new. It is smooth and doesn’t have a lot of grip so we are sliding about a bit. It reminds me of my youth because the corners are tight, so it is a bit like a go-kart track, but it’s great to drive. Going through those two stadiums, one is a fake one, but one is a real baseball stadium… I think it is an awesome atmosphere."
AS IT HAPPENED: Mexican Grand Prix FP2
Eric Silbermann's Mexican grumpy preview
Technical analysis: United States
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