Karting Caster and Toe In/Out

What Is Caster?

Caster goes hand in hand with camber. However, instead of moving the Kingpin from side to side (as with Camber), caster is adjusted by moving the Kingpin forwards or backwards.

Moving the Kingpin backwards, towards the driver will add caster. Moving the Kingpin forwards, away from the driver will remove caster.

Caster can be used to add more grip to the front of the kart. This is done by moving more weight to the front by adjusting the height of the front ride height. This will also change the wheelbase of the kart, making it shorter or longer.

To get a kart to corner properly, the inside rear wheel needs to lift off the ground. Adjusting caster can help with this. Without caster, the inside wheel would never lift, causing huge amounts of understeer.

When Should You Adjust Caster?

In most cases you will be adding caster. Adding caster will give you more front-end grip. You will find that the rear of the kart will be freer, meaning you will be able to accelerate out of corners much easier. This makes it great for hairpin corners and tight angles.

You will also need to add more caster in wet conditions and when the track is slippery. This will help to reduce understeer when you turn into corners. Adding caster does make the steering stiffer though, since you will need to be moving more weight, but in the wet the additional steering will allow the kart to turn faster.

You might ask yourself why you would need to reduce the caster at all. If you need more straight-line speed, reducing caster will give you an advantage. This is specifically helpful with lower horsepower karts. If a driver is finding the steering too heavy when cornering, reducing the caster will make it lighter & if the inside rear tyre is lifting too much, reducing caster will reduce the lift.

Less caster will give you lower rolling resistance. This also makes it a useful set up if you’re on a fast and flowing track that doesn’t have many sharp corners.

When to increase caster:

Understeer

Rear inside wheel is not lifting

Kart is lying flat through the corner

Rain or slippery conditions

When to decrease caster

Kart is physically hard to steer

Kart is hopping during cornering

Too much wheel lift of the inside rear tyre

Two-wheeling

What Is Toe?

Toe in and toe out refers to the angles of the front tyres. However, unlike camber, this setting refers to the ‘top down’ angle. In other words, if you were to look at the kart from a bird’s eye view, you will notice the front tyres either pointing outward, away from each other, or inward, toward each other.

This is a simple set up tool that can be adjusted, however is not used by many drivers. It has similar effects to camber. It can affect the amount of grip the front end of the kart has, and the sacrifice is straight line speed and higher levels of wear on the tyres.

Too much toe in or toe out can cause excessive wear to your tyres and slow down your kart on the straights. The general rule for adjusting toe is the following:

More toe out (wheels pointing away from each other) – creates more aggressive turn in.

More toe in (wheels pointing toward each other) – creates more stability in your kart.

If you want the highest straight-line speed you need to run completely neutral toe, which will give you the least rolling resistance.

Most karts will run between 1-2mm toe out per side to help with the balance once a driver sits in the kart. This can be increased to 3-4mm per side in the wet conditions to help with steering.

When Should You Adjust Toe?

In most cases you will add toe out to your kart to get the highest possible grip on the turn in phase of the corner. Most drivers set and forget this and only change it when the weather conditions change significantly.

Drivers don’t tend to use toe in too much, as more speed is generally found in corners rather than the straights, but it’s not something to rule out. So try toe in (1mm each side) to see if it works for your class, tyre and circuit. You might just find that hidden advantage over your opposition!

Karting Camber

Camber is something that is often talked about when it comes to cars and motorsport. Did you know that it’s a key set up tool that can make you faster in karting as well?

If you don’t know what camber is or where to begin adjusting it, don’t worry. In this episode we are going to cover everything you need to know about camber. It’s an important set up tool that can help you become the fastest driver on track.

On top of that, camber is a set up element that is used throughout all forms of motorsport. Even if you move up to cars, you can still adjust the camber on your tyres to get the best out of them.

What is Camber?

Before we can use camber to go faster on track, we need to understand what it is and how it will affect our kart’s tyres. Drivers often ignore camber settings because most guides make it way too complicated to understand.

Camber is basically the angle that the tires have. If you lie flat on the ground in front of the kart and look at the tyres you can easily see the camber settings. It’s best to look at the top half of the tyres, this is where camber has the most effect.

There are three basic camber settings that you can spot with the naked eye.

Neutral Camber – This is the factory setting that you will receive your kart in. The tires will be an equal distance apart.

Negative Camber – This setting means that the top parts of the two front tires will be closer together. From the front view, it will look like the tops of the tires are pointing towards each other.

Positive Camber – In this setting, the bottoms of the tires will be closer together. When you are looking from the front of the kart, the top halves of the front tires will be pointing away from each other.

Basically, what camber does is change how much of the tyre is touching the ground. Essentially, you will be changing what is called the ‘contact patch’ between the rubber and the tarmac. Each camber setting has different advantages and disadvantages.

Adding positive camber means there is less contact between the tyres and the road. The result is that the steering will be lighter, but you may find that you have a bit less grip in the corners. This is because there is less rubber that can grip onto the road. However, the advantage here is that you will have better straight-line speed since there is less rubber touching the tarmac which slows you down.

Reducing camber, to neutral or negative camber will make you slower on the straights. However, this will give you more grip in the corners since there is more rubber touching the tarmac. You may notice that the steering becomes stiffer and more difficult to hang on to during corners too. If the track has a lot of rubber on it and too much grip you will notice that the steering becomes shaky. This is when the tyres have too much grip and you will begin to slow down in corners.

Higher performances classes tend to use negative camber as they require more grip to corner at greater speeds.

You can check the camber settings on your kart just by looking at the tyres. If your tyres are a few laps old, you can look at where they are starting to grain and wear out. If the line is in the middle, you have neutral camber. If it’s more towards the inside of the tyre you have negative camber, and it the wear is more towards the outside of the tyre you a running positive camber.

Camber requires very small adjustments. You can easily overdo it, or even unbalance the tyres. The left and right tyres always need to be the exact same measurement, otherwise the kart will be unbalanced, and the tyres will wear unevenly.

For example, if you want to add 6 millimetres of positive camber, you need to adjust the camber by 3 millimetres on each of the front tyres. Adding 6 millimetres on both tyres will mean you have added 12 millimetres to your camber set up.

How To Use Camber To Your Advantage

Camber can be a tricky setting to play with. If you get it wrong, it can throw off the balance of your whole set up. In general, this is a good rule to follow: positive camber means less surface contact, and less grip. Negative camber means more surface contact, which creates more grip.

Remember that there are a lot of variables you need to consider when you adjust your camber settings. For example, if it’s raining you will need more contact between the tyres and the road, so you would opt for a negative camber.

On the other hand, if a track has too much rubber it will already be offering high amounts of grip. If you have too much grip your kart will begin to struggle. This problem could arise as the rear of the kart hopping when it goes through a corner. The issue is that when the tyres have too much grip there is too much resistance, which makes it more difficult for them to rotate.

You can use different camber settings between races and qualifying. For example, if you need your tyres to heat up quickly and get up to temperature, you can add negative camber. The increased contact between the track and the tyres will make them heat up much faster.

However, the problem with this is that the tyres can overheat very quickly too. If you’re going into race conditions and you need your tyres to last longer, then you need to add more positive camber to your set up.

Adding more positive camber will also give you better straight-line speed and acceleration. If you think your opponents have an edge over you on the straights, a small camber adjustment could do the trick, but you will be sacrificing some cornering speed.

In terms of how different camber settings feel during cornering, they each have their own unique cornering styles. In the examples below, we will use extremes. This means that you might not experience the same thing with small camber adjustments, but rather if you were to run a full positive or negative camber.

Neutral camber for example, will give the kart more precise turn in during a corner, but it might oversteer slightly throughout the corner and be a bit less stable on the exit when accelerating.

If you set the camber to a positive setting in comparison, the kart will grip less when turning into corners, and you might find that you will need to turn into corners earlier to hit your apex. The rear of the kart will be planted on the exit of the corner, and you can accelerate earlier and faster out of the corner.

If you were to set the camber to a negative setting in the same scenario, you might have an extremely sharp turn in, but you will find yourself fighting the kart with oversteer as the rear will lose grip before the front. You would also find the kart to be a lot slower on exits and straights with the extra contact between tire and track slowing it down.

You need to test each setting to see which one you are most comfortable with, and which one you are fastest with. Understanding your own driving style will help you to quickly identify which one is best for you.

Front end adjustments