Pirelli has allocated the C3 hard, C4 medium and C5 soft for this Saturday's Azerbaijan GP, one step harder than last year's C4, C5 and C6. Yet what worries Pirelli is not wear but temperature. The long flat-out run from the final corner to Turn 1 cools the tyres, and the warning is that this raises the risk of front lock-ups into Turn 1.
Why C6 is out: nobody used it in last year's race
Last year Pirelli brought the C6 as the soft to Baku, but it was never used in the race. According to Scuderia Fans, drivers preferred the medium because it was "consistently easy to manage", and the C6 never became a serious race option. 2025 data compiled by F1 LivePulse shows the hard covered 62% of all race laps (average stint 31.4 laps) and the medium 38% (average 20.4 laps). Eleven drivers started on mediums and nine on hards, and everyone made one stop.
This year each driver gets two sets of hards, three mediums and eight softs, with one extra set of softs for Q3 runners. In dry conditions at least two different slick compounds must be used.
The straight cools the tyres, regenerative braking cools the brakes
The official F1 website says Baku's smooth, low-abrasion asphalt means "very low wear and degradation", and names a one-stop as the most likely scenario. Even the C5 soft should be capable of fairly long stints, and the hard may be all but ignored in the race. The long flat-out sections encourage tyre cooling, however, so temperature management is the key, it adds.
Scuderia Fans went into more detail. The flat-out stretch linking the final corner and Turn 1 cools the tyres, and that effect has become more pronounced as wheel rim design has evolved. On top of that, regenerative braking has made it harder to build brake temperature in the traditional way. Pirelli has already observed an increase in micro lock-ups under certain conditions in the early races of the season, and Baku is a track where the problem could show up even more. Ultimately, teams must solve an equation in which tyre temperature, brake temperature, energy recovery, traction and straight-line efficiency are all intertwined.
By F1 LivePulse's metrics, Baku rates 5/5 for traction, 4/5 for braking, among the lowest of the season for lateral loads, 1/5 for asphalt abrasion, 2/5 for initial grip and 5/5 for track evolution. Graining may appear early in the weekend but should ease as rubber goes down. The C3 hard may be hard to warm up at this circuit.
Strategy: medium and soft are the race tyres
A one-stop is the baseline, and the C4 medium and C5 soft are likely to be "the most useful race tyres". The average pit loss is around 19.5 seconds. With the range one step harder than last year, though, last year's hard (C4) is this year's medium and last year's medium (C5) is this year's soft, so how many of the eight sets of softs to save for the race is a question that will start to be answered from Thursday practice. Qualifying is on Friday and the race on Saturday.