A kerb on an F1 track is completely different from the type of kerb found on a normal street. Unlike a street kerb that cannot be crossed, an F1 kerb can usually be crossed easily. Kerbs are used to define the edge of the track, but there are a few different types of F1 kerbs to be aware of.
F1 kerbs vary in height, width, and materials used, depending on where on the track they are situated. From sausage kerbs to painted kerbs, these crucial parts of an F1 circuit tell a driver they are at the limits of the track. Kerbs can slow down or even damage the car if driven over.
Hitting a road kerb at 200 mph is a bad idea for both driver and vehicle, so in F1 the kerbs are fairly gentle. There are penalties for misusing them, including damage to the car or a decrease in speed. In the article below, we’ll take a closer look at how kerbs work in F1 and the different types.
Why Do F1 Tracks Have Kerbs?
F1 tracks have kerbs (or curbs) to define the limits of the circuit. F1 drivers need to avoid going off the track and potentially damaging their cars or getting injured. Kerbs also guide drivers to stay within track limits, so that they don’t gain an unfair advantage.
Kerbs in F1 come in varying forms, and there are surprisingly many uses for them. It’s not just a case of the track being on one side and the no-go zone on the other, although that’s part of it. Due to Formula 1 racetrack being quite flat and the cars bombing around at eye-watering speeds, the brightness of the kerbs helps drivers maintain their driving lines throughout the race.
Most F1 kerbs are painted red and white and are bolted to the ground to make moving them after races, or for any course changes to a track, easier to manage. Sometimes, the kerbs are literally painted onto the asphalt itself using a non-slip paint, and while these are much less intrusive for a car to ride over, still come with the expectation that drivers try to stay on the inside of them.
Staying On Track
Another use for kerbs keeping drivers on the track, aside from reducing the risk of damage to the car, is that the kerbs clearly define where a driver can and cannot overtake a rival car. The kerbs already give a clear indication of what line a driver should try to keep to, and the longer the race goes on, the more defined this line becomes as rubber from the tires makes it even clearer.
Overtaking another car by going outside the kerb-defined track limits will result in the overtaking car having to relinquish the place they have just taken. Repeated offenses will result in the driver being penalized even further. Track limits are now usually defined as the white line on the inside of the kerb all the way around the track.
This means that, if all four of a driver’s wheels go outside of this white line at any point, they have breached track limits and may receive a warning or even a penalty. However, drivers can still use kerbs for the fastest line around the track if they stay within the white line with at least one tire.
What Are F1 Kerbs Made Of?
The materials F1 kerbs are made of depends on the function they perform. Some kerbs are painted onto the asphalt in order to create the effect of a boundary, while others may be made of concrete or even artificial grass.
As each corner can be different in some way, from the speed that a driver heads into it to the acceleration that they use to exit a corner, the kerbs used differ depending on their location. Kerbs even differ from track to track, where a type of corner at one track may have a sausage kerb, and another may have a normal kerb.
Most of the time, the kerbs are painted red and white. This is primarily to make them as easy to see as possible, although some racetracks do paint the kerbs in alternative colors, usually the color of that country’s national flag. Kerbs that are made of other materials are also often painted to highlight the edge of the track. Metal kerbs, for instance, are also painted.
Varying Degrees Of Kerbs
Metal is another material used to make F1 kerbs. This type of kerb is bolted to the ground and painted to maximize visibility. The advantage to using these metal kerbs is they can be raised to varying heights, allowing greater control over the track by the race organizers. A metal kerb can differ in size on an inside corner compared to an outside corner and differ again on corner exits.
Some metal kerbs are quite shallow and barely raise above the track. Cars often ride over these in their attempts to gain a time advantage, although speed can be affected due to a loss of grip. Even with a non-slip paint coating the kerbs, during a wet and rainy race there is an increased chance of a car slipping when driving over the kerb.
Fake Kerbs And Artificial Grass
Artificial grass is used on some kerbs. It’s attached to the outside of the kerb to help drivers recover when moving off the track. Artificial grass looks neat and often allows a driver to find better grip before returning to the track, although in wet conditions the grass can be notoriously slippery and treacherous to drive on.
At times, multiple types of kerbs are used on the same stretch of the track due to safety concerns or to offer more leeway to drivers, depending on the severity of the track at that point. A metal inner kerb can be on the inside of a raised outer kerb, sometimes called a scraping kerb, and while these outer kerbs can be driven onto, there can be damage to the underside of the car as a result.
Can F1 Drivers Drive Over The Kerbs?
F1 drivers can drive over kerbs, although it’s often a disadvantage to do so. At certain points on the circuit, a driver might drive over a kerb to trim an entry corner on an apex in order to save time. Many F1 kerbs can be driven on safely, but some are to be avoided at all costs.
Before every race, many drivers and teams will do a full walk around the circuit to look over the driving lines, kerbs, and any other points that need taking note of. The importance of this track walk cannot be overstated. Knowing before the race which kerbs are at key driving areas is vital and can help teams find their perfect strategy.
Once a driver has a feel for which kerbs are potentially dangerous to the car, they can make every attempt to avoid driving over them during a race. And because every racetrack is slightly different, the kerbs are not always as uniformly positioned as some would like.
Knowing that one corner can be taken aggressively, and another should be skirted to avoid damaging the car, can help a driver make the right decisions during a race. A driver will already have a plan for which racing lines they should take, so avoiding a dangerous kerb can be a game-changer.
Overtaking Off Track
We’ve already touched on the fact that overtaking off the track has repercussions. A driver deliberately going off track to get past an opponent must relinquish his position for the other driver to retake their position in front.
Before every F1 race, a line is marked out at every kerb situated on a corner. The FIA states that if a driver crosses this line with all four wheels, a penalty is incurred. Every driver is aware of this before racing, and every driver will attempt to keep at least as much of the car as possible inside these markers.
For a first and second offense, the driver is merely warned. On the third occasion, they are penalized with a 5-second pit-stop. The kerbs on an F1 track are there for many reasons, especially for safety and for keeping a race fair by forcing all drivers to stick to the track itself. Any driver abusing the fact that a kerb is easily driven over will eventually be caught and punished.
Avoiding Sausage Kerbs
Unless there is no choice, or the car is going too fast and the driver has made a mistake, avoiding a sausage kerb is a must. With the many documented accidents that hitting this kerb at speed causes concern for drivers, a driver must be aware of where every sausage kerb is on each track in order to avoid it at all costs.
What Are Sausage Kerbs In F1?
Sausage kerbs are the largest kerbs used in F1. They are essentially small ramps that are often used on corners that can be taken at high speeds, but they may appear at chicanes too. Sausage kerbs prevent drivers from taking corners too wide at high speed. Sausage kerbs are controversial in F1.
Those that feel sausage kerbs have been a help to F1 believe that their inclusion on racetracks has led to drivers being more careful to avoid cornering as wide as they previously did. Many drivers and constructors believe that the sausage kerbs have done more harm than good. Several high-profile accidents over the past few years have highlighted that sausage kerbs can be tricky to avoid.
Ignoring The Kerb
Ignoring a sausage kerb can cost a driver dearly, and that’s before the potential for having an accident is taken into consideration. A driver choosing to go over a sausage kerb at speed can be given warnings, penalties, and in the case of qualifying laps, having their lap time canceled.
Hitting a sausage kerb at the wrong angle or speed can result in horrific crashes, as seen in 2019 when F3 driver Alex Peroni’s car took off after it hit a sausage kerb situated on the Parabolica corner at Monza. Peroni was lucky to walk away from the crash. His car did several flips in the air before it crashed into fencing and came to rest off the ground, surrounded by metal poles and netting.
Another highly unfortunate incident happened between Max Verstappen and Lewis Hamilton, at Monza, in 2021. While trying to overtake Hamilton, Verstappen’s Red Bull car hit a sausage kerb and ricocheted on top of Hamilton’s Mercedes, taking both drivers out of the race and leaving the Red Bull car on top of Hamilton. The cars weren’t even going very fast at the time.
The Fate Of Sausage Kerbs
For now, sausage kerbs seem to be here to stay, although with the FIA constantly looking at ways to improve safety in F1 races, there is always the chance this could change. Many drivers are critical of this kerb, and if more accidents happen, there is the real possibility that the FIA will seek a different type of kerb for these high-speed corners.
What Do F1 Rumble Strips Do?
F1 rumble strips perform the same purpose as they do on public roads. They cause a vibration and loud rumbling noise when a driver drives over them. Rumble strips let the driver know there are near the edge of the track and could potentially hit a kerb or spin out.
In F1, a rumble strip alerts a driver that they are in danger of driving off the track. They are at best a deterrent to keep a driver on track, and at worst pointless, as drivers often drive on the rumble strips so they can shave time off a lap. An F1 driver will often use the extra width that a rumble strip offers so they can find an even wider line before cutting into a corner.
Another use for rumble strips is to prevent the cars from cracking the asphalt of the track. Most of a Formula 1 track is made of asphalt, but the the outer edges of apex corners are sometimes mixed with concrete, which is in turn covered with a rumble strip. The lateral force exerted from driving through the corners would eventually cause the track to crumble and the rumble strip deters this.
Are Rumble Strips A Good Idea?
There has been no real noticeable decline in speed when a driver uses the rumble strips to drive on, and if they remain on track, no penalties are incurred. Some cars, especially if they are having some minor issues already, try to avoid the rumble strips as the added vibration can cause further mechanical issues.
The FIA seem to be happy with having rumble strips at tracks, and the drivers take full advantage of them when possible. There is little to no discernible grip loss for the tires that are on the rumble strip, although when it’s wet, they can be a little trickier for drivers to drive over safely.
Final Thoughts
Kerbs in F1 mark the boundaries of the track. Drivers can drive over kerbs, but some can cause damage to the car. If a driver overtakes while taking too much kerb and exceeding track limits, they are forced to give the position back. If it happens several times, they can incur a penalty.
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