Mercedes had to overcome “obstacles” in F1 test

Although the seven-time world champion topped the times on the final day of running, the three days of action have not been completely smooth for his Brackley-based team.

In particular, Mercedes has battled the porpoising phenomena that most teams have faced to a greater or lesser degree, and it still faces some work in trying to find a proper solution for the next test in Bahrain.

Amid a consensus that Ferrari and McLaren have had the most positive of week of testing,…