Inside Revolution: Foundations for Success

Thursday 24 August 2023

Karting is the fast-paced proving ground for future motorsport talent. When every element of performance is crucial, what does it take to create a winner? Revolution investigates.

Revolution is available online, as a PDF download and on the Revolution app (for both iOS and Android devices). 

One of the most typical routes into motorsport, karting is an exciting but highly competitive environment. Tiny time differences cover multiple grid positions, and races are often won by narrow margins. Top drivers are able to set consistent lap times at the front, but also use superior racecraft to cut through the field when required. 

Motorsport UK offers a Karting Pathway with different categories and classes to enter. To perform well you must know how to get the very best out of your kart, and out of you, the driver. 

The Kart

Much of the baseline for your potential performance is in the kart you choose, but with a range of different options on the market, deciding which is the best can be confusing.

Alex Short, Team Principal of karting outfit S8 Racing, currently supports a group of talented and competitive drivers from six-years-old. “A lot of people choose their kart on where they are based,” he says. “For example, PFi has a lot of IAME X30 [karts], but further down to the south you will probably see more Rotax [karts].

“When you look at the detail, however, it is the same kart, the same chassis, but the engines are different and that makes them perform differently. The Rotax karts have more bottom-end to the engine with a bit more grunt, so a heavier driver may prefer them, while a lighter driver may be more suited to X30.”

Although there are wide range of kart brands available – Fullerton, Charles Leclerc, Robert Kubica, Tony Kart, OTK, Birelart, to name a few – many have similar baselines with different tweaks to design. Selecting the right option, and whether to go new or used, can feel like a minefield, but there is guidance to available.

“You have the option of everything from a new machine all the way to a well-used kart,” adds Short. “For your first kart, go somewhere in the middle – a kart that looks really cheap has probably done a lot of work, or may not have been very well looked after. Always try to push to the top of your budget to get something that has been well looked after.

“When it comes to used karts, there is plenty of things to look out for. As there is no suspension on the chassis, karts do a lot of work twisting through the corners, so the metal can crack, be re-welded and painted over. Also, the underside takes a lot of abuse over the kerbs and that can flatten frames out and make them thinner.

“We would typically advise that something below £2,000 has had a harder life. If you are looking between £2,500-£3,000 for a used kart you normally get something a bit better. Cadets are little bit cheaper because they are smaller.”

Gary Chapman runs ProTrain Racing kart school and team and adds: “You will also find a particular kart might suit certain tyres or circuits. For example, the OTK range is particularly good with the Mojo tyres used in the Rotax Championships, while other manufacturers do better on the Komet tyres, which are used in the IAME Championships.”

Set-up

Once you have selected your machinery, getting the best out of it is all about the set-up. Arrive-and-drive Championships, such as those run by Club100 and The Daniel Ricciardo Series, put the focus on the driver by limiting what can be changed on the kart. This can make it more budget-friendly, but most Championships allow a wide variety of areas to be adapted, modified, or replaced.

Chapman says that there is “possibly more you can do on a kart than a car,” but fortunately most machines are relatively simple to operate. Having a professional team on hand can provide a huge benefit, particularly when it comes to knowing what manufacturers produce the best parts, but they also come at a cost.

Whether you are with a team or go it alone, however, there is one core aspect to focus on. “The key to a kart’s handling is to get the inside wheel to lift off the ground,” says Chapman. “It may only be half a millimetre, but you will not go around the corner until you do that. It is like a train – if both wheels are on the ground, you cannot go anywhere but straight.

“Everything we do on set-up is aiming to achieve that. The major factor in achieving it is the caster on the front. That controls how much the rear wheel lifts up, but we also have the stiffness – if you make the kart stiffer it is more likely to lift up the wheel – and the weight distribution, the camber, the ride height, and the rims.”

Short explains: “On a race car, there is a differential, so when you go into a corner, the inside wheels slow down and the car turns. In a kart, it is a fixed rear axle, so we have to break traction off the circuit. If the kart does not lift, it just slides around the corner, and you will lose all momentum. And that will destroy your lap time.”

The caster is the forwards and rearwards tilt angle of the bolts – known as kingpins – on which the stub-axles pivot and, ultimately, it determines how much weight is transferred to the front end and off the rear inside wheel. A fully loaded caster results in better corner entry, although that then creates a knock-on reduction in traction on exit.

“If the kart is sitting a bit flat, we might increase the caster to make it lift higher and if it is lifting too high, we do the opposite,” explains Short. “On the rear, we can change the axle stiffness, so if the inside wheel is lifting too high, we soften the axle to sit the kart down. Changing an axle takes 5-10 minutes and caster adjustments are 2-3 minutes.”

The stiffness of the kart is determined mainly by the wall thickness and material of the axle tubing, but modern karts also have torsion bars – mainly on the front but also occasionally on the rear – and different hubs and stub axles with different thicknesses can be fitted to the rear to also adjust the stiffness.

“Everything is incremental,” explains Chapman. “In this area, it could probably make about a tenth of a second difference to your lap time with the different things you can do. They will sometimes add up together, or sometimes cancel each other out, but maybe you could find two or three tenths if you changed a number of items.”

Wheels and Tyres

As you would expect, new rubber is always going to give you a major time advantage. In the British Championships, tyres are provided by Komet in X30 (with Dunlops for Cadets); Mojo in Rotax (apart from MiniMax, which is also Dunlop); Le Cont for KZ2 and Bambino; Maxxis in KTM and Dunlops for Honda.

The key to getting the best out of those tyres, however, is not only new rubber but also the tyre pressures. Adapting the settings to suit the track and the weather is one of the most vital and tricky parts of karting set-up, and knowing what type of asphalt you will be running on can make all the difference.

“If we have a rough surface, we run a low tyre pressure because the tyres move around a lot, whereas on a smooth circuit we can run higher pressures,” explains Short. “GYG in Wales, for example, is a very rough surface so we run as low as 6psi, whereas PFi is really smooth, and we will run up to 11psi.

“If you run a higher pressure on a rough surface, the tyre will quickly overheat and lose grip. On a smoother surface, if you run the pressures too low, the kart just bounces around a lot. You need to change your driving style depending on the pressure, too, as low-pressure tyres move around more so you have to do more coasting through the corners.”

Tyre wear and overheating is just a big an issue in karting as it is all the way up the ladder in Formula One. An aggressive driver will get through the tyres faster and a heavier driver will also heat them up more quickly. However, there is one trick that can help manage those tyre temperatures and keep things in check.

“The wheel rims themselves have different grades,” explains Short. “Sometimes we will use a magnesium wheel, because that dissipates the heat a lot faster. We use them more in the summer. At other times, we may use a wheel which is half magnesium, half aluminium, and that keeps more heat in the tyres for a cold day.”

Engines

To ensure the racing is fair, and offers good value for money, the engines are run to a set of standard rules, and little can be done to them. However, the nature of mass manufacturing, as well as the effect of general use, means that despite every engine being made to the same formula, there can be significant differences in performance. 

Short adds: “With a 30bhp engine, one horsepower is massive, so people use dyno machines and swap parts from one engine to another to get the best performance possible. If you can gain one or two tenths, in timed qualifying that could be 15 places.” 

There are also gains to be made in other parts of the engine and drivetrain, including adjustments on the carburettor – which controls the amount of air and fuel going into the engine – and to the sprockets between the engine and axle – which transmit the power from the engine to the wheels. 

“Changing the sprockets can give either better acceleration or better top speed,” explains Short. “We use data from the circuits as the start point, but on the day, depending on the weather, the track may be performing better, so we can run a smaller sprocket, or if the track is a little bit damp, we have to put a bigger sprocket on. 

“Different drivers may drive differently, so one might need a little bit more help out of the corner while another may want more speed at the top end. They can also adjust their engine performance when out on track by using a dial on the carburettor to move between high and low jetting to increase or reduce power.” 

“If you combine all the engine improvements, you get massive difference and on the chassis side, newer ones will handle better,” says Chapman. “But gains can also be achieved for less when it comes to set-up – a set of good rims are £500, while different casters can be as little as £50. That is one of the most vital things on a kart, and it is relatively cheap.” 

Driving Technique

When it comes to the driver, and their influence on karting performance, the most important factor is one that many beginners get wrong. Getting yourself in the right position is a fundamental part of becoming a good driver, because when you get it right, your body will work as a part of the kart’s structure. 

Just like the engine is a part of the structural integrity of a Formula One car, the body of a karting driver helps to hold everything together. Terry Fullerton has trained some of Britain’s best talent in the last three decades and he explains: “To be fast and consistent, you have to sit in a way that you can be on top of the steering wheel and control your body in the cart. 

“Inexperienced drivers, particularly younger ones who have not been taught any technique, very often sit in the kart wrongly. There is a habit these days of sitting too far away from the steering wheel, so the driver is hanging onto the wheel and going around corners lying on the outside of the seat, letting the seat hold you in. 

“Instead, you should be holding yourself in place. I teach drivers to actually push on the steering wheel, as opposed to pulling, so the majority of the control is with the outside arm. If it is a right-hander, for example, the left hand is doing most of the control and when you go around a left-hander, it is the right hand. 

“Once people start to master the push technique, they move forward quite quickly because it alters the way the kart handles, it alters your speed through an apex, and it alters your consistency too. If you are not holding yourself properly in the kart, you will wobble in the seat under braking, get a counter-effect on the steering wheel and sway into corners.” 

Fullerton, who famously raced and beat Ayrton Senna during their karting days together, also says that moving your body to lean into corners is a “very bad thing” and recommends that one of the best ways to work on positioning is to get someone to take photos of you in the kart and analyse them. 

“If you look at a photo of someone doing it right, you can see they are holding themselves and that the seat is not holding them in at the top of the rib cage,” he adds. “You should be using your body and your shoulders for steering. That is the technique to driving a non-gearbox kart fast. And it works everywhere.” 

Seat Positioning 

To get the driver position just right, the seat should be fitted in a central location with the steering and pedal positions moved and set to suit. Short explains: “If a smaller driver sits nearer the front, they will have less rear grip than a taller driver. However, the smaller driver is also carrying lead ballast to reach minimum weight, so that can also be moved around.” 

The kart and driver weight must be the same for everyone, so lighter drivers have ballast they can use to their benefit. Some keep it centralised, but others move it around to help tune the set-up and short adds: “You can move it more to the front to help someone who is struggling on turn in, while if you move it to the back, it will make the rear more stable.” 

Braking

After driver positioning, the next most crucial element is braking, which Chapman says is what makes the difference between a driver at the front and somebody in the midfield. The key is having the ability to reduce speed quickly and efficiently, to be at the right speed for the apex. 

“The skill is in braking as hard as you can without it actually locking up because the moment you lock up, you are not slowing down as efficiently,” he explains. “You have to be able to go straight from zero to that position immediately, you cannot gradually brake as you go into a corner because you are wasting time. 

“If you get that right, then it is simple power from the apex. If you get the power on before an apex, a kart will sit flat, put the rear wheels down and want to understeer – because it has not got that inside wheel up. After that, it is just about maximising all the track, using every centimetre you can into a corner, through the apex and then back out again.” 

Vision 

Karting, from the outside, appears like a frantic form of motorsport with lots of rapid direction changes, drivers jinking left and right as they jostle for position and clattering over bumps and kerbs in a long buzzing nose-to-tail chain. From the inside, however, the best drivers are in a serene rhythm, with their focus far beyond where they actually are. 

Vision, and where to place it, plays an important part in any racing, and Fullerton says: “Often an inexperienced and nervous young driver will just look at the rear bumper of the kart in front. When that slows down, they brake and when that goes faster, they go. But that is a recipe for accidents and all sorts of problems. 

“You have to look past the karts in front. Your eyes should be above and looking at the apex of the corner you are coming up to. That is something that it is possible to teach and see the results easily, because you can spot when a driver is not doing it properly in the way that they follow like they are connected on a rubber band.” 

Racecraft 

The techniques that are used to put together a quick single lap remain crucial for racing, but learning the art of competition is an entirely different skillset. In a fast, tight, and intense field of karts, performance is all about being able to think fast and find the gaps. Theory can only go so far, and real racing technique can only come through practice. 

Club race meetings, says Chapman, are an ideal training school for overtaking, because many in the UK do not have timed practice. “The grid is decided using a calculated random method for the front section, middle section and rear section,” he explains. “When you are at the back, that gives a driver an excellent opportunity to learn how overtake. 

“At National and European level, it is all timed practice, and I believe British drivers have an advantage over our European rivals because of the Club style system. We have had a lot of fast overseas drivers come to us, but they cannot overtake because they have grown up in a timed practice world where, if they are quick, they never have to pass anyone.” 

Data Analysis 

One area where time and performance can be gained is by looking at data. At the top level of car racing, engineers spend thousands of hours analysing the information coming from the cars, and the top level of karting is very similar. However, it is vital to understand when to bring data analysis into the equation. 

“When you have a driver that is a long way off the pace, a coach’s vision, watching what they are doing, is most important,” says Chapman. “As you go higher up the scale, the marginal gains become harder to find and that is when delving into the data becomes more and more important.” 

When Fullerton started, there was very little data available to help a kart driver analyse their performance, but over time that has changed. He admits he does not go deep into data analysis himself, but while he agrees it can be “very useful” if it is used right, he believes the old-school techniques of lap time analysis can be just as valuable. 

“When I have worked with teams that do data analysis, we have been able to identify things that you cannot really do old-school,” he says. “But there are also a few things that you can do without data – for instance, by watching karts out on track and doing split times. You can quickly spot if someone is particularly fast and try to analyse why. 

“You can learn a lot from other drivers that are fast but if the quickest drivers are not in your team, you cannot access their data so that is when taking split times on the quick drivers can be a benefit. On the flip side, if you are the fastest driver in the team, you have everything to lose and nothing to gain, because everyone is looking at your data! 

“You also have to be careful not to misinterpret data, which can very easily happen. For example, you might think a particular motor is faster on the straight, but there can be a number of other reasons why the kart is faster. You often have to be able look past data to understand it. People say the data cannot lie, but sometimes it can.” 

Mindset 

A lot of performance in a kart comes from simply having confidence in your machinery and your ability, and that comes from having belief in your technique. If you can feel when a kart is breaking away and you know what to do when it happens, you will have confidence to push that little bit harder. And that is when you can get close to the limit.

“About 90-95% of what the top drivers do on the track is in their subconscious,” Fullerton says. “The conscious part of the brain is only really working a very small part of it, and actually, they have to work hard to break through into their subconscious when they are trying to learn a new technique. 

“There is a lot of sports psychology in the top end of karting nowadays, as there is in many sports, and most of the kids that were doing very well in Europe who I helped four or five years ago all saw sports psychologists on a pretty regular basis. There are quite a lot of techniques you can do that seem to work very well.” 

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