I am confused as to why the lap times have been steadily increasing during testing as the tyres wear. Here are 2 graphs from http://abulafiaf1.wordpress.com/. Abulafiaf1 is a member here.
Graph from 27 February posting. This graph of Kobayashi (dark, Sauber) and Maldonado (light, Williams) clearly shows the lap times increasing each lap.
Graph from 1 March posting. This graph shows 3 last year lap times: Schumacher (black), Vettel (blue) & Hamilton (yellow) against Rosberg (red) at the Barcelona test. Clearly last year the tyres were pretty consistent as they wore down (but were said to ‘fall off the cliff’ once completely worn). (Note, Rosberg’s lap times have been adjusted to compensate for the colder temperature but the change each lap is not affected by that.)
On a slick tyre I can’t understand why there would be steady lap time increase as the tyre wears – a flat surface of the same rubber is being used all the time. The fuel load is decreasing each lap which makes the car go faster. Any explanation (Jersy Tom)?