How to Drive Double-Apex Corners in Karting
A karting double-apex corner is a single bend where the fastest line reaches the inside twice: once at an initial apex, then again at a second apex later in the corner. The kart usually moves away from the inside between those two points before returning to the kerb.
The important decision is not simply whether to hit both apexes. It is where to position the kart between them and which apex should control your speed. In most cases, the second apex matters more because it determines how early you can straighten the exit and apply full throttle.
What makes a corner a double apex?
A double-apex corner can be created by several different layouts:
- A long corner with a constant or changing radius.
- A corner that tightens after the initial turn-in.
- A bend leading into a short straight or another important corner.
- A linked sequence where the first part appears to be one corner but the exit is controlled by a second change of direction.
The two apexes are not always marked by two separate kerbs. Sometimes the first is a temporary reference point and the second is the true point where the kart should finish rotating toward the exit.
An apex is the point where the kart is closest to the inside of the corner. In a double-apex corner, the first apex is normally earlier and the second apex is closer to the exit. The kart may touch the inside kerb at the first point, move slightly away from it, and then return to the inside for the second.
The second apex usually sets the line
The most common mistake is treating both apexes as equally important. They are not necessarily equal. If the corner leads onto a meaningful straight, the second apex controls:
- How early the kart can be pointed at the exit.
- How much throttle can be used before the corner is finished.
- Whether the kart reaches the exit kerb under control.
- The speed carried down the following straight.
For that reason, the best line often sacrifices the first apex. You may turn in later, miss the first kerb slightly, or run a little wider in the middle so that the kart is better positioned for the second apex.
This is an example of corner prioritisation: giving up speed in one part of a corner to gain more speed at the part that has the greater effect on the lap time.
Start with the exit, not the first apex
Before choosing your turn-in point, identify what follows the double apex.
If the corner leads onto a straight, the exit is the priority. If it leads directly into another corner, the next corner may matter even more than the double apex itself. Your line should create the best position for the next piece of track, not simply produce the fastest-looking path through the current bend.
Ask these questions during track walking or practice:
- Where does the kart need to be when it reaches the second apex?
- How much road is available on exit?
- Does the next straight justify an early throttle application?
- Is there another corner immediately after the exit?
- Does the first apex help the kart rotate, or does it force the kart too tight too early?
A useful starting assumption is to make the second apex the main target, then adjust the first part of the line around it.
The usual positioning sequence
A strong baseline line through a karting double-apex corner normally follows this pattern:
- Approach from the outside of the track.
- Brake in a straight line or with only a small amount of steering applied.
- Turn in later than you would for a simple single-apex corner.
- Aim for the first apex without forcing the kart tightly onto the kerb.
- Let the kart move slightly away from the inside after the first apex.
- Rotate the kart again toward the second apex.
- Unwind the steering and use the full exit width.
The amount of movement between the apexes depends on the corner. In a long, smooth bend, the kart may remain close to the inside and make only a small release toward the middle. In a tightening corner, moving away from the first apex is more important because it creates the space needed to turn for the second.
Do not treat this as two unrelated corners. The kart should make one controlled change of direction, with the first apex setting up the second rather than ending the first half of the turn.
Braking and turn-in
Braking should normally be completed before the kart reaches the first apex. Karts have no differential, meaning the rear axle is fixed and both rear wheels are connected. When the kart is turned, the inside rear wheel needs to unload or lift slightly so the kart can rotate. Excessive braking while turning can make that rotation abrupt and difficult to control.
A practical approach is:
- Brake firmly while the kart is relatively straight.
- Release the brake smoothly as you begin turning.
- Use the initial steering input to rotate the kart toward the first apex.
- Avoid adding more steering than necessary as the kart approaches the middle of the corner.
The exact braking point depends on the class, tyres, grip level and corner speed. A heavy or late brake may make the first apex easy to reach but leave the kart pointed too sharply toward the inside. That usually produces understeer or forces a second lift before the exit.
If the kart is not rotating, the answer is not always more steering. Try a slightly later turn-in, a cleaner brake release, or a small adjustment to entry speed. More steering can overload the front tyres and make the kart run wide at both the first and second apexes.
How much speed to carry between the apexes
The middle of the corner is where many drivers lose time. They enter with too much speed, reach the first apex, then have to wait with partial throttle while the kart slides or refuses to rotate for the second apex.
A better line often feels slower at the first apex but produces a more stable kart afterward. You should be able to:
- Keep the steering angle relatively controlled.
- Avoid a large correction after the first apex.
- Begin squeezing the throttle as the kart points toward the second apex.
- Reach the second apex with the kart ready to open its steering.
Throttle should not be judged only by whether the kart is technically on the racing line. If applying power pushes the front wide, the kart is either carrying too much entry speed, turning too tightly, or using throttle before it is sufficiently rotated.
In a rear-driven kart, throttle can also change the balance. A gradual increase may help stabilise the kart, while an aggressive application can make the rear step out or push the kart wide. Use the throttle to finish the rotation and accelerate away, not to force the kart through the first half of the corner.
Choosing between common line options
Early first apex
This line reaches the first inside kerb quickly and may feel natural. It can work when the corner opens significantly after the first apex or when the second apex has little effect on the following section.
Its weakness is that it often leaves the kart too close to the inside. The driver then has to wait, add steering, or lift before reaching the second apex.
Late first apex with a stronger second apex
This is the most useful default for a tightening double-apex corner or one leading onto a straight. The kart turns in later, uses more of the track in the middle, and arrives at the second apex with a better exit angle.
The first apex may be missed by a small amount. That is not automatically a mistake if the kart remains stable and the second apex and exit improve.
One continuous inside line
Some fast double-apex corners do not require a visible move away from the inside. If the radius is consistent and the exit is open, the fastest path may be a smooth arc that stays near the kerb and touches two natural inside points.
Do not create a mid-corner gap simply because the corner is described as double apex. The line must follow the geometry and the available grip.
Kerbs and track limits
Kerbs can help define the intended line, but they are not always the fastest or safest surface. A kerb may unsettle the kart, reduce grip, or make the steering bounce wide. This is especially relevant in rental karts, where the chassis may already be difficult to rotate, and in low-grip conditions.
Use the first kerb only if it helps the kart turn without compromising the second part of the corner. The second kerb is usually more valuable when it marks the exit apex, but it still must be used within the rules and without causing the kart to bounce onto the outside of the track.
Kerb rules vary by circuit and championship. Some events define track limits by painted lines, while others restrict specific kerbs or require all wheels to remain within a marked boundary. Learn the local rule before building your line around maximum kerb use.
How to diagnose a poor line
Your exit position gives useful evidence about what happened earlier in the corner.
You reach the first apex but miss the second:
- You probably turned in too early.
- Entry speed may be too high.
- You may be holding too much steering after the first apex.
You hit both apexes but run wide on exit:
- The kart is not rotating early enough.
- You applied throttle before the steering could be opened.
- You entered with too much speed and used the entire available grip.
You reach the second apex but are slow afterward:
- The second apex may be too early.
- You may be staying on the brake too long.
- The kart may be pointed correctly but carrying too much steering lock, preventing clean acceleration.
The kart feels slow at the first apex but fast on the straight:
That can be a successful line. Compare the exit speed and distance gained after the corner rather than judging the line by the first apex alone.
A practical method for finding the line
Begin with a conservative, late-apex approach. Mark three reference points: braking, first turn-in, and second apex. Focus on making the kart stable and repeatable rather than immediately searching for the most aggressive entry.
Then make one change at a time:
- Move the turn-in slightly earlier or later.
- Adjust entry speed by a small amount.
- Change how close you run to the first kerb.
- Start throttle application earlier or later.
- Compare the exit speed and your position at the end of the following straight.
If you have data logging or video, watch steering and throttle together. A fast line normally shows a smooth reduction in steering after the second apex and a confident throttle increase as the kart exits. Large steering corrections, repeated lifts, or a delayed throttle application indicate that the line is not yet setting up the exit properly.
The key principle
When deciding where to position the kart in a double-apex corner, do not aim automatically for the first visible inside kerb. Choose the line that gives the kart the best second apex and the cleanest exit for the next section of track.
In most tightening or exit-critical corners, that means a later turn-in, a less aggressive first apex, controlled movement toward the middle, and a precise second apex. Once the kart is rotated and the steering can open, apply throttle progressively and use the available exit width.
The fastest karting double-apex corner is usually not the one that looks quickest at the first apex. It is the one that leaves the kart pointed correctly when acceleration begins to matter.