Bahrain Test 2 – Pirelli: C5 shunned by all, Mercedes skips even C4. During the second Bahrain F1 test, most teams avoided the Pirelli C5 tire.

As announced a few days ago, on the eve of the first session at Sakhir, Pirelli made all five tire compounds developed for the 2026 F1 season available to the teams.

Team choices for the second F1 test session

However, given the challenge of using the tires on a track particularly demanding on rubber, only a handful of teams decided to follow Pirelli’s suggestion and use all five sets. Only Williams, Aston Martin, Alpine, and Cadillac opted to request the C5 tires, essentially two sets, with the American team requesting just one. This means that only a single driver will actually run the C5 compound.

Mercedes went further, not only ignoring the C5 but also skipping the C4. For the Stuttgart-based team, little will change compared to the first test, as George Russell and Matteo Antonelli will continue to focus on gaining familiarity with the C1, C2, and C3 compounds.

Session details and tire markings

The second session will take place from February 18 to 20, with the tires visually differentiated as follows: C1 and C2 will feature white logos, C3 and C4 will display yellow logos, while the C5 will be marked in red.

Compounds sharing the same color will still be distinguishable because the harder of the two will have the sidewalls decorated with a checkered flag pattern. The C2 and C4 compounds, however, will feature no sidewall decoration, showing only the Pirelli and P Zero logos.

The lack of interest in the C5 compound during the second Bahrain test suggests that F1 teams are prioritizing long-run stability and thermal management over outright qualifying speed as the 2026 season nears. Mercedes’ decision to even ignore the C4 indicates a high level of confidence in their baseline data—or perhaps a cautious approach to the abrasive Sakhir surface. As Williams, Aston Martin, and Cadillac prepare to sample the red-walled C5, the contrast in testing programs will provide the first real clues into who is focusing on race trim versus those looking for ultimate mechanical grip. Whether Mercedes’ conservative strategy pays off will only become clear when the first competitive lights go out in Melbourne.