Throughout the course of a Formula 1 race, it is likely that you will hear drivers communicating with their race engineers about the use of prime or option tires. This can leave many viewers wondering what the difference between these two tires is and how it affects the race.
The prime tire is harder and more durable, whereas option tires are softer and grippier. As it is mandatory for drivers to use two different tire compounds during a race, it is of great strategic importance as to when teams decide to deploy both their prime and option tires.
The choices that teams make are dependent on both the track conditions and the situations unfolding during the race. In this article, we’ll discuss the benefits and negatives of hard and soft tires, as well as the reasons F1 teams must use two different tire compounds during a race.
What Is The Prime Tire In F1?
The prime tire in F1 is hard and durable but less grippy than the option tire. Drivers that start with prime tires usually wait a bit longer before their first pit stop. This allows them to use the clean air in front of them while other drivers are pitting to make up for the relative lack of grip.
As the first part of the race is generally slower due to a buildup of traffic and jostling for position, it can be beneficial for a driver to know that they have a fresh set of softer tires waiting for them so they can complete the final 25% of the race with a faster, grippier set of tires.
However, there are downsides to starting a race with harder tires. The added weight of a full fuel tank will mean that they become more susceptible to wear at a faster rate, shortening their lifespan and making the driver pit earlier than they would have liked. Also, the cars that did pit earlier will be able to gain ground with their fresh tires until the driver’s hard tires are switched out.
What Is The Option Tire In F1?
The option tire in F1 is softer and has considerably more grip than a prime tire. It’s also vulnerable to a quicker rate of wear and tear. Softer tires are usually stickier, which allows cars to take corners quicker, accelerate more, and brake harder without locking up.
Because of the obvious benefits of softer tires, it would make sense for a team to use them throughout the entire race, but F1 rules require two tire compounds to be used. With the different characteristics of each track, teams will make the most of the Friday practice session to determine their race strategy and work out the best time in the race to use their softer option.
Option tires are grippier because they generate higher levels of friction. Think of it as dragging a soft eraser across a table. Instead of gliding across, it will try to stick to the table. The same effect applies to softer tires on the track. In hot conditions, the rubber becomes even softer, producing more friction.
Soft tires operate best at close to 100°C/212°F, which is why teams wrap them in blankets before the drivers head out onto the track. Harder tires operate best at higher temperatures, meaning they take longer to warm up, but they also wear slower, meaning they are useful for longer stints.
Different Types Of Tires In F1
Of course, F1 teams aren’t just restricted to hard and soft tires. There are currently seven different tire compounds available to teams, with six ‘slick’ tires for dry weather, along with an intermediate option for damp to fairly wet conditions, and a wet-weather tire for when there is a lot of water on the track.
Three of these tire types will be available during a race at the discretion of tire manufacturer Pirelli, with drivers having to use at least two of them throughout the race. The tires available will be chosen depending on the heat and surface of the track. The slick tires are graded from C0 to C5, with C0 being the hardest tire and C5 being the softest.
The tires are color coded, with hard tires displaying a white stripe, medium having a yellow stripe and the softest tires having a red stripe. Should it be a wet race, intermediate tires will have a green stripe and wet tires will have a blue stripe.
Characteristics Of Wet Tires
Whereas slick tires are manufactured to be smooth, allowing for more rubber in contact with the track, wet and intermediate tires are lined with grooves, which allows water to pass in between the track and the tire. If an F1 car was to race in wet conditions with slick tires, there would be very minimal tire-to-track contact, resulting in the car skidding out, known as ‘aquaplaning.’
On the other hand, if a wet tire were to be used on a dry track, the compounds used to manufacture it would mean that it would quickly overheat. Intermediates are the middle ground in this situation, as their shallower grooves allow them to race in damp conditions or on a drying track, albeit without the maximum efficiency that the other tires would provide.
The shallower tread of intermediate tires will shift 30 liters of water per second per tire when the car is at racing speeds, which is why they will be utilized on tracks with minimal surface water. Wet tires can disperse up to 85 liters of water per second, giving cars as much grip as possible during the really wet sessions.
How Many Sets Of Tires Do Teams Receive Per Race Weekend?
Teams are notified which tires they will be using two weeks before the race. Teams will receive eight sets of soft tires, three sets of mediums and two sets of hard tires which must last them the whole weekend. Should rain be forecast, they will receive three sets of wet tires and four sets of intermediate tires. An additional set of intermediate tires will be handed out for wet practice sessions.
Teams must hand their tires back after each session for regulatory checks and must keep a set of soft tires spare if they make it to Q3. The FIA operates a digital tagging system to monitor the tires used by teams.
Why Do F1 Drivers Have To Use 2 Different Tires In The Race?
F1 drivers have to use 2 different tires in the race to mix up the racing strategies used by teams in order to make the sport more tactical and strategic. The rule applies to all cars during a dry race, but if it’s a wet race teams no longer need to use two different compounds.
The rule also makes the most of the fans’ appreciation for pit stops and the intrigue that they provide, especially when a car is in and out of the pits after a full tire change within a matter of seconds. Mandatory pit stops also provide constant differentiation in leaderboard positions, adding further excitement for fans.
There are exceptions to this rule, however. Wet sessions don’t require mandatory tire changes because it would be unsafe for drivers to have to change out of their wet tires should heavy rain persist. Wet tires are very durable because of the way they are designed, as well as the cooler temperatures reducing much of the risk of overheating.
Because of this, it is possible to see cars go a full wet race without pitting, although this is uncommon. Should there be a let up in the rain, it is also very likely that a driver will switch to their shallow-grooved intermediate tires in order to gain a bit of extra speed in the race.
Would Drivers Pit If This Rule Didn’t Exist?
Modern tires are just not manufactured to last a full race. Even if teams weren’t required to switch their tire compounds, a set of soft tires would certainly not be durable enough to maintain high speeds throughout the distance of a race. And although harder tires would get a car farther, they would still likely need to be swapped out at some point or the driver would lose a lot of performance.
If the rule didn’t exist, cars would likely pit more often throughout the race to maintain constant use of softer tires. While it may increase speed, it would eliminate the differentiation in the race strategies employed by teams that keep Formula 1 so interesting.
Final Thoughts
Prime and option tires have become part of the most important strategic decisions that an F1 team has to make and have a big effect on a race’s outcome. The mandatory tire change has also given fans insight into the technical side of F1 and provides them with the excitement of regular pit stops.
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