28 February 2014 Last updated at 15:49

Formula 1 testing: Pirelli boss predicts two or three-stop races

Pirelli's Paul Hembery believes Formula 1 cars will make "two or three stops" during races in 2014 after analysing data from the latest test in Bahrain.

The Pirelli motorsport director tells BBC Sport "teams are trying to find a "delicate balance" between conserving fuel and maintaining enough car performance to make the tyres heat up and grip the road more effectively.

Force India's Sergio Perez was quickest on day two ahead of Fernando Alonso's Ferrari and the Red Bull of Daniel Ricciardo.

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