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Enough of the aesthetics, now the power beneath the bonnet

For two weeks, I lightly discussed the aesthetic aspects of skin-deep motor vehicle design.

More detailed explanations will follow at a later date, but for now let us look at the other important design factor; performance.

While looks, and ultimately the outright appeal of a car, tend to be subjective and rely heavily on individual tastes (and strength of eyesight), the physical capabilities fall under a more exact science and can thus be taken to be the universal truth.

Judging a car’s appearance is as simple as eyeballing it, so how is the performance of a car measured?

Acceleration is first, most commonly expressed in 0-100 km/h times, or 0-60 mph in medieval units of measurement.

Quarter mile runs, standing kilometre, half mile and full mile figures are also quoted, which also give an idea of how fast a car accelerates, as does the observed speed at the end of the given acceleration distance.

Braking is next, and the most typical statistics quoted are 100 km/h to 0, 200 km/h to 0 (the McLaren Mercedes SLR does this in less than 65 metres, similar to a Ford Focus at half that speed, and the McLaren’s is almost half the distance that a Ford Anglia takes to brake from half the McLaren’s speed).

For the Bugatti Veyron’s 400km/h to 0, you will have covered a good four football field-lengths by the time this happens. Both distance and time intervals are usually quoted.

Last up is the cornering grip, the ultimate holding power of the tyres-suspension-chassis-centre of gravity-steering geometry collusion point.

This is usually expressed in terms of centrifugal acceleration, better known as lateral g. 1g is the numerical equivalent of the earth’s gravitational field constant, determined by Isaac Newton to be steady at 9.81 m/s2 (metres per second per second, or metres per second squared).

Braking and acceleration are also sometimes expressed in g. But a lot of us fear mathematics and physics, and don’t particularly care for numbers and SI units, especially that last part.

There should be a way of giving a single parameter that neatly sums up all those numbers.

Only really obsessive buffs, like yours truly, derive any sort of pleasure reading numbers on a multi-column table and comparing them to more numbers on other multi-column tables, and it is for this exact reason that normal production cars are taken to race-tracks to try and establish a respectable lap time.

After all, the lap time of the car neatly sums up everything: acceleration on the straights, braking coming up to the corners and the cornering ability through the corner, all rolled into one.

To bring a semblance of order in this (there must be hundreds of thousands of racetracks around the world), and for the sake of uniformity, there are a few racetracks worldwide that have been accepted as the benchmark determinants of a motor vehicle’s capabilities, and the most famous, the most dangerous, the most demanding and the most fun to drive is found in the Eifel Mountains in Germany.

Die Nürburgring (The Nuerburgring): The Green Hell: Seventy kilometres south of Cologne and 120 kilometres northwest of Frankfurt sleeps the medieval village of Nurburg, and around this sleepy hamlet loops the world’s most famous racetrack: the Nuerburgring.

The track is an unnerving 20.8 kilometres long in its current public-accessible format. Over the years, the track has changed configurations, and is at the moment split into the 22.8 km Nordschleife (Northern loop) which we are concerned with, and a 7.7 km Südschleife (Southern loop), mostly used for circuit race events such as F1, though the Nordschleife is still also used for some events.

There is a very good reason this track bears the nickname “The Green Hell”, and not just because several racing drivers have come to their ends along it over the years. The place is unforgiving and very few mistakes, if any, go unpunished.

There is little run off, the corners (of which there are countless) and crests are blind, so getting your line wrong or setting your car up badly will not end well.

The issue is that it is also a high speed arena, so driving slowly will only get you rear-ended by ambitious Germans in hard-charging 911s. It is not a place for the inept or the weak at heart.

This is exactly why auto builders bring their new-fangled hardware here in search of glory. Even the drivers have to be carefully selected when cars are put to the test: the driver too has to go the distance, not just the car.

Driving at an average speed of 160 km/h through more than 100 hairpins, sweepers, S-curves and crests for almost 10 minutes is sure to put a lot of pressure on both man and machine.

To cap it all off, there is a 300 km/h long straight at the very end, where high horsepower cars can really show their mettle, but on days when the track is opened to the public, drivers are required to slow down here, rather than speed.

This is how the lap times are significant, again to both driver and car. If you drive an ordinary car (200hp or less, say) and crack 10 minutes, you could be a bit special behind the wheel.

Less than 9 minutes and you might need the 200hp, or a little more; or better yet, superhuman driving skills. Between 8 minutes and 8 and a half calls for some 250hp plus.

Anything less than 8 minutes, in any car, and you would be advised to quit your day job and seek employment as a factory driver for any of the major companies.

The most hard-core sports cars have their lap times ranging in the early 7 minutes, at the hands of professional drivers.

So far only three production cars have broken the 7 minute barrier, and even so, two of them are not really road legal (the Radical SR3 at 6:57, an open-top racer with a motorbike engine and the first to register a sub-7 minute lap time; the Ferrari 599 XX, and the Pagani Zonda R, at 6:47, which took the record recently).

The Top Gear Test track: A lot of you must be familiar with this place, if only from the on-screen television marvel that is the BBC Top Gear show and its housekeeper, The Stig.

But are you aware that it is another unofficial test arena for motor cars, and that most manufacturers keep a keen eye on how their vehicles perform here?

The Power Lap Board, as it is now famously known, has been a make-or-break feature for vehicles participating on the show, and is something that is actually taken quite seriously, notwithstanding the zoo-like antics of one Jeremy Clarkson (he sometimes sets fire to the strips of paper on which the car’s lap time is written).

It is hard to actually tell what the track looks exactly like just from watching; all we hear is “Chicago”, “Gambon”, “Hammerhead”, “Follow-through” and so on, but extraordinarily, the track layout is in a figure of 8, meaning it would be worse than useless for holding a race (someone had once suggested that they should hold a Formula 1 race there).

Fancy names aside, all those corners and straights did not just fall out of the sky into view of BBC TV cameras; they were all designed intentionally — by the Lotus Group no less, meisters of automobile handling and chassis setup.

The track is usually run anticlockwise for the first loop of the figure 8. The first corner is a left curve of reducing radius (also called Willson Bend, but this name is rarely used), coming after a high-speed left-right kink on the opening straight.

Next up is Chicago, a steady state circumventing a tyre wall. Steady state corners are those taken without steering correction (constant application of lock), and the motor vehicle’s angle of attack is adjusted either using the throttle or the brakes.

This bend was purposely built by Lotus to expose a chassis’ propensity for either oversteer or understeer.

After that comes Hammerhead, a tightish left-right switchback that tests chassis balance, braking and brake balance, and the effect of hard braking on a car (tramlining, yawing or locking wheels).

This bend also shows up understeering chasses on entry into the second bend (the right after the left), or oversteering chasses as you exit the whole thing.

From there comes a right sweep that feeds into the follow-through, where the vehicles are maxed out, shooting past the tyre wall (again) into a left sweeper called Bentley (another rarely used name) and in to the second-to-last corner as it has now been known, another hard left and regarded as the trickiest bend in the whole course. It is easy to spin out on this bend by oversteering.

If you don’t oversteer into the grass (or spin wildly) through the penultimate corner, then the final corner will definitely get you.

Called Gambon, this corner has been the undoing of several high ranking individuals up to and including, but not limited to The Stig himself (it was named Gambon after Sir Michael Gambon took it on two wheels in an earlier season of Top Gear).

Besides Sir Gambon, other persons of note taking that corner on two wheels include Hollywood actor Tom Cruise and a former Arsenal player.

From there it is on to the start/ finish line. All this covers 2.82 kilometres. The lap time of any given vehicle through that course goes onto a board, called The Power Lap Board.

There are rules governing that board, first being that only vehicles available on sale in the UK can have their times posted on it.

Other rules include street legality (the appearance of number plates and indicator lamps confirm this), the ability to go over a sleeping policeman (a flattish speed bump) and the use of street tyres.

This means cars that are too low at the front, or cars running on slicks are not allowed, as are limited production cars that are sold out.

This does not deter the team from timing anything they can get their hands on. Formula 1 cars have had their chance to shine there, and the lap record is held, not by a car, but by a fighter aircraft, the Sea Harrier jump jet, at 31 seconds.

Not being anything roadworthy (not a car, not street legal, and not using road tyres), its time cannot be posted.

Most cars, particularly the top ranking marques on this board, would not be instantly recognisable to a good number of you out there, so I will not dwell too much on the merit list, but a few key facts: the first Veyron slotted in fourth position first time it went round, and was further dethroned rapidly in succession by a Zonda F roadster and a Caterham R500.

The successive Super Sport took the honours, but has now been unseated by a V8-powered Ariel Atom 500 at 1 min 15.1 sec.

Ehra-Lessien: Pronounced “error le scene” (including accent and inflection), this is a top secret test facility that became famous because of the Bugatti Veyron.

It is not used by just anybody; exclusive rights of ownership, management and use belong to the giant Volkswagen Group, the same posse of excessively clever people who engineered the Veyron.

While it covers 96 kilometres of any imaginable tarmac track condition, the most spectacular stretch is the 8.8 kilometre long arrow-straight section.

So straight and so long is this section that it is possible to see the curvature of the Earth’s surface along it, and it is here that the two Bugattis (407 km/h Veyron and 431 km/h Veyron Super Sport) set their respective production car speed records.

The stretch is parenthesized by two banked corners, usually taken at 200 km/h for those planning on clocking 400 km/h along the straight. It is one of few places on Earth where this is possible.

Nobody sat down and decided that the Nuerburgring and the Top Gear test track would be the benchmark facilities for determining a vehicle’s physical abilities, it just happened.

It has come to be that any sports car manufacturer who wants to build a name for themselves brings their vehicle to the Nuerburgring and sets a lap time, which they would shout about if it beats that of their competition.

Nissan and Porsche got into a scandalous tiff when the R35 GT-R beat Porsche’s 911 Turbo, causing Carlos Ghosn (head honcho at Nissan) to brag endlessly and Porsche to throw a wobbly, accusing Nissan of dishonesty.

Nissan returned for the second time and posted an even better lap time, after which they bragged even harder (“The Legend Is Real”, so goes their YouTube video showing the Nissan conquering the ‘Ring).

Ferrari set a lap record with the 599 XX car, but their rivals Pagani showed them up a few short weeks later with the Zonda R, making Ferrari’s one of the shortest-lived lap records ever, and leaving Pagani as the current holders of the mantle.

Maybe we should build a track of our own here and get in on the action.

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Overdrive: Keep it off when overtaking or lugging loads

If there is one thing any columnist tries to avoid, it is repeating oneself. Unfortunately, I will have to do just that this week.

I had talked about overdrive earlier, but reader feedback suggests I left a lot of unsatisfied curiosities out there, so we will have to put aside the happy-go-lucky merry-making of test drives and racing this week and step back into the lecture theatre.

Class is now in session, and the topic today is automotive transmission characteristics in general and two things in particular: the overdrive unit and Continuously Variable Transmissions — close relatives of the typical automatic gearbox.

The Overdrive Unit

This is one of the most misunderstood aspects of automotive transmission systems, especially when coupled to an auto-box.

Let us start with the overdrive unit in a manual transmission car as it is easier to explain away. In some instances, it is used as a standalone gear, just after top (1-2-3-4-O/D).

In such a case, the top gear of a car channels power directly from the clutch past the gearbox to the differential unit, with no gear reduction whatsoever.

With overdrive, what you have is a gear taller than top, in a reverse situation where, instead of gearing down, now the unit gears up the entire powertrain.

The overdrive unit/gear gives the gearbox a higher output speed than input speed (in top gear, both input and output speeds are the same).

It is usually used for cruising in low load situations because it keeps engine speeds low thus saves fuel and reduces wear and tear on the engine.

The other type, used in old British sports cars was the type you engaged or disengaged at will. It provided intermediate gears for the manual transmission, such as third-and-a-half (taller than third but just below fourth).

In those days three-speed and four-speed boxes were all the rage, so the gearing was interstellar at best to cover the high-torque, low-speed demands met by the lower gears and still provide power-sensitive top end zoom in the higher gears.

For the sake of example, let us use third and fourth. Shifting up and down between third and fourth is not only annoying for the driver, but it also impedes smooth progress and affects fuel economy.

An intermediate gear becomes necessary, let us call it third-and-a-half. The only way of getting this gear 3½ without changing your entire gearbox is to use an overdrive for the third gear, giving the intermediate ratio.

This overdrive could also be used for the other gears, even reverse. Nowadays most manual transmissions are six-speed, so the overdrive gear has been rendered unnecessary.

In automatic powertrains, the overdrive unit is a bit more complex. Long ago, it was a selectable position in the auto-stick, P-R-N-D-O, but nowadays, it is electrically activated by a push-button, commonly found on the gear lever itself. For practical purposes, we will look at the overdrive unit in a Volvo car:

The overdrive unit uses an epicyclic gear set, which is in essence a set of gears, one nestled inside the other, almost concentrically, if you will.

It is not entirely dissimilar to the planetary gear set used in most auto-box transmissions, except that it is not so far-reaching and versatile.

When engaged, the driveshaft connects to the carrier gear, the outermost gear set of the epicyclic arrangement.

When the carrier gear turns, the internal gears rotate slightly faster. The innermost gear set is called the sun gear, and it rotates much faster than the outer planetary gears courtesy of the diverse ratios.

The sun gear is the one connected to the drive axles, which turn the wheels of the car. In a nutshell, the sun gear (output) rotates much faster, at higher rpm, than the carrier gear (input).

Pressing the O/D button on the gear lever (turning it on, in this case) sends an electronic signal to a switch located within the transmission that engages the overdrive gear.

The end result is reduced engine speed for a given road speed, which in turn means improved fuel economy and less engine strain. For cars with high torque outputs, this could also mean a higher top speed.

So when to use it? I’ll tell you when NOT to use it. Leave it off when lugging heavy payloads, when going up steep hills, when overtaking or accelerating hard and when off-roading.

In other words, where high torque application is necessary, using overdrive is self-defeating. Also, do not use overdrive when going downhill and depending on engine braking to keep your speed in check.

Engaging it will allow the car to “run away”, seeing that the rev range necessary to provide sufficient compression resistance to slow the car down might correspond to much higher road speeds than anticipated.

Leave it on during ordinary driving, though. The benefits are enormous. However, some people claim that using overdrive when passing slower traffic may boost your speed, but this is only applicable in cars with high torque outputs.

Try that in a Vitz, on a small hill, and you will see dust.

Continuously Variable Transmissions

This is an adaptation of a typical automatic gearbox, and some of you may have across it. Have you ever driven a car with what looks like an auto-box, but vehicular acceleration is not at par with engine revs?

The car may accelerate rapidly but the engine revs stay constant, and those who are keen may have asked: what the…?

No need to curse, it is called a continuously variable transmission, and is the only gearbox you will ever find anywhere with an infinite number of gears.

Such are common in Euro-spec and JDM Nissan road cars: it debuted in the second-generation Primera saloon, and has seen action in the minuscule Micra and of late, the second-generation X-Trail crossover.

Even some Toyota Opa cars have this type of gearbox, and most interestingly, those silly go-karts that scared me half to death in South Africa’s Cape Province depend on this type of transmission too.

This is how it works: Unlike your typical gearbox which sports distinct toothed wheels (cogs or, better yet, actual gears) the CVT setup uses belts and pulleys that vary ratios infinitely between low (first gear, for maximum torque) and high (top gear, for maximum speed) and everything in between, all steplessly, hence the claim of having an infinite number of gears.

The most common type of CVT (and the one we will dwell on today) is the belt-and pulley system. This setup uses two opposing cone-shaped variable-diameter pulleys connected by a chain or metal belt.

One pulley is mated to the engine (input shaft) while the other is attached to the wheels via the driveshaft. Each pulley is made of movable halves.

When the halves move apart, the pulley diameter reduces as the belt slides down the cone faces, and the belt is forced to ride lower.

When the halves move closer, the belt slides up the tapered cones and the pulley diameter increases.

Changing the diameter of the pulleys can be done in indistinct steps, and this varies the transmission’s ratios, i.e. the ratio of the rpm of the input shaft to that of the output shaft, which in essence is what a typical gearbox does.

The only difference is in the other transmission types, this is done in distinct steps: the gears themselves. Think of the CVT the same way as a 10-speed bicycle directs the chain over a number of smaller gears to multiply torque.

To maintain the tension in the belt, as one pulley reduces its diameter, the other increases its own, and all this juggling is what creates the infinite gear ratios.

Making the input shaft pulley diameter as small as possible and the driveshaft pulley as big as possible gives “first gear”: maximum engine revs giving minimum road speed.

With acceleration, the pulleys vary their diameters to optimise the engine speed/road speed relationship, up to a point where the input pulley is big and the output pulley small for lower engine speeds and higher road speeds: that is “top gear plus overdrive”.

All this is made possible through sensors and microprocessors. The CVT, however, sounds odd; if anything, the noises coming from under the hood would suggest a transmission failure of some sort in other powertrain configurations, but it is perfectly normal for a CVT.

Also, the seamless power delivery would give a feeling of lethargy from behind the wheel when in actual fact the CVT can outperform other conventional transmission types. As such, CVT cars are still struggling to find acceptance in society.

To counter this, car manufacturers have had to inculcate some features that are in direct contrast to CVT characteristics, such as the creep feature like you would find in a normal automatic, and “gear simulation”, distinct steps in the transmission progression.

Driving a car with a CVT is a bit disconcerting. Even before the unusual acceleration at constant engine speed, stomping the throttle at take off makes the car sound as though the clutch is slipping or the automatic gearbox is failing: there is more noise than movement as the car adjusts the engine speed and road speed for the most appropriate relationship.

The reliability of CVTs has also been brought into question as they are delicate by nature. However, more robust construction has made them able to handle more powerful engines.

Initially, the CVTs used earlier could not handle more than 100 hp, but the current ones are capable of channelling up to 290 hp (Nissan Altima) to the tyres form the engine.

Just how good is this type of transmission? For starters, it was banned in Formula 1 because it was making the cars too fast(!).

It is also used widely in farm machinery, from tiny garden John Deere tractors to full-scale combine harvesters.

The benefits of a CVT are more usable power, a smoother drive and better fuel economy; though how this works out I don’t know.

The Gen-II Nissan Primera with a CVT returned a mere 23 mpg (7 kpl) from a 2.0 litre 4-cylinder engine. Maybe the economy figures have improved since then.

There are other forms of CVT, such as toroidal, hydrostatic, ratcheting and infinitely variable transmissions, but I doubt if I want to get into all that here and now. Maybe later.

Fun fact: The great scientist Leonardo Da Vinci actually invented the CVT back in 1490. Daf (from the Netherlands) put the first CVT into automobile application in 1958, and only in 1989 did the first US-sold production car have a CVT: the Subaru Justy GL hatchback.

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Behind the wheel… in a very uncomfortable, rigid go-kart

Up until I landed in the RSA, I had borne some prejudices about go-karts.

They are mostly driven by nine-year-olds, rarely crack 60 km/h, have no gears, and lack power assistance: no power steering, no brake boosters, no power windows (in fact, no windows at all), they use tiny tracks for their races, and their closest motoring equivalents are cane tractors, or Formula One cars.

Only crazy people would ever bother to race in them. That was until I found myself in one.

Inside

There is no distinct interior.

Outside

There is no distinct exterior either.

So now what?

You slide into position on top of the metallic skeleton of something that looks like a tea tray.

Your left foot is on the brake, which may or may not work (left-foot braking is hard to master, take it from me), and your right is on the throttle, which may or may not work.

The seat is metal, a mere three inches off the ground. You have a tiny, noisy single-cylinder “powerplant” underneath your right armpit (mid-engined layout. There is a rear-engined option where the mill is behind the seat), and this whole setup is suspended on slicks, which may sound fancy but they are ridiculously small.

It is a little difficult reviewing a racing machine, so instead what I am going to do is narrate how the whole go-kart experience went down.

During one warm autumn Monday afternoon two weeks ago, we took a break from driving Jaguar XJs in the Cape and switched to go-karts for a bit of good-natured fun and racing.

There were five of us journalists and two of our hosts, alongside three or four test drivers from Jaguar-Land Rover.

We were split into three groups of four drivers each, seeing that there were only four go-karts available, one of which was the track-mistress’ “Ferrari”, her pet machine, simply because it had a plastic bumper while the rest did not.

Each group had a turn at the track, members battling against each other for asphalt supremacy. After a brief orientation (during which time I discovered that I was the only one in that whole clique who had never driven a go-kart), our group was selected to go first. I was up against a fellow Kenyan and two South Africans.

The rules were simple: Do not operate both throttle and brakes simultaneously. Go hard, but have fun and enjoy yourself.

Respect the flags: a blue flag meant move over, you are being overtaken, a black-and-white striped flag was a warning, a black flag meant disqualification (also equal to two black-and-whites), the red flag meant the race had been stopped and of course the black-and-white chequered flag meant the race was over.

I was planning on forcing the blue flag on everybody else that day. Whether or not that happened you will discover in a moment.

The first lap was the warm-up lap, to warm the engine, tyres, and give drivers a feel of the machines. It was low-speed and non-competitive, followed by 10 screaming laps of hammer-and-tongs jousting and then one slow, non-competitive cool-down lap after the final flag.

Shower caps (I swear that is what they were) were distributed, over which helmets were donned. My helmet squeezed my face into a nasty scowl, giving me that mean and uncompromising race-driver look.

All the more perfect for the championship that I thought was headed my way. So, there we sat, helmets stewing our brains in that autumn afternoon sun, four abreast, as the track mistress walked from one kart to the next cranking the engines.

Sitting on the extreme right of the field meant that I was last out of the pits, my engine being started last. I took the opportunity to gripe a little about the floppy throttle pedal and the floppy brake pedal.

All I got was a curt “I know” from the track mistress before she flagged me off. Here goes. Now, you do not drive a go-kart, the go-kart drives you.

Sounds corny, yes, but that warm-up lap was a real revelation as I discovered that, unlike other machines which react to driver input, in go-karts the driver reacts to the input of a wilfully wayward, unpredictable, noisy, uncomfortable contraption that does its best to embarrass you in front of your peers.

Left foot braking is also extremely difficult, made more so by the unusual driving position. It feels like sitting in stirrups, ready for childbirth, with the knees splayed apart to make way for the saucer-size steering wheel and each foot on either side of the steering column.

Bathroom break

The warm up lap ended with me trailing the second-last driver (fellow Kenyan) by a clean 20 seconds.

On a track that size, there could only be one of two explanations: either I took a bathroom break halfway through the lap (unlikely) or my ineptitude behind the wheel of a racing machine is a lot worse than I initially thought (more likely).

The runoff area was good foresight on the designer’s part because it gave overambitious, understeering incompetents an extra half a second to mull over their mistake before smashing into the tyre wall.

This sharp bend led into the “main straight”, about 30 or 40 metres long (compare to the Nurburgring’s main straight, which is almost three kilometres in length), followed by a 90-degree left and then a series of hairpins and finally a sweeper back to the starting line.

The first three laps of the actual race saw me fall behind at an alarming rate, right up to the point where getting lapped by the leader (a hard-charging Jaguar test driver) was becoming less a possibility and more a probability.

I was not going to go down without a fight, so I opened the taps, put my foot down, and let it rip. It turns out that in karting the brakes are purely for stopping, not slowing down.

I found out that you are meant to drive a go-kart flat out, no partial throttle openings, and I also found out that the racing slicks offer insane levels of cornering grip, meaning you can turn at almost any speed.

This would all be fine had the steering not been set in concrete: turning the wheel requires full-arm movements, all the way from the shoulder, not the swift wrist-flicks that are seen in Formula One race footage. Racing karts is hard on the body.

My new driving tactics saw me close the gap within the next three laps, until I was tailgating my compatriot menacingly on the seventh lap.

That was when it happened: the blue flag went up. Move over Kenyan, for your fellow Kenyan wants to pass you.

Rules are rules, and exiting the first corner on the eighth lap, my colleague drove into the runoff area to let me by and I swept past my countryman to slide into third position. Hah!

The first overtake of the day, and it was done by me. Sadly, that was it; the rest of the field were driving like maniacs and come the tenth lap, I was still third. Not bad for a start.

The next set of races came up. This time round I was in the final heat, so I watched the first two incident-packed races with a sense of trepidation as people unleashed the latent Michael Schumachers in them.

Overtaking became more ambitious, tailgating more intense, drafting closer, powerslides more spectacular and there was one retirement: a Zimbabwean journalist understeered into the wall at turn three, sending tyres flying several feet into the air in a classic display of incompetence that drew raucous laughter from the rest of us once we established that the only injury he suffered was a bruised ego.

That was the only red flag of the day, as the race had to be restarted. Restarting a race means you start in formation, so there was a bit of drama as the second-placed driver tried to creep past the leader at the starting line before the flag went up.

Legs amputated

What made the accident all the more special was the fact that the Zimbabwean was driving the track mistress’ “Ferrari”.

We surmised that the plastic bumper probably saved him from having his legs amputated. He chose not to continue racing.

The last race of the day, and I was facing some veritable competition in the form of experienced kart drivers.

This time I was up first, and a hard truth made itself felt during the warm-up lap. While my original kart had floppy foot controls, the pedals on this other machine had no give whatsoever, and the result was I did the warm-up lap brakelessly and cruising on the puny torque available at tick-over (idle). I decided to carp again.

“The throttle and brake pedals are too stiff, ma’am, they are not moving at all”

“Push harder!” Then the flag went up. By the end of the first lap, the scope of my difficulties was obvious to everyone present.

The whole field was bunched up behind me (a dangerous thing in racing), and the other cars were weaving left and right looking for the smallest space to push past the time-wasting Sunday driver up front (me) and get on with real racing.

I got my first blue flag, so I drove into the run-off area to let them by and they all swept past. All three cars.

In less than two seconds I had lost pole position and was now dead last. Abashment does not come any worse than that.

It got progressively worse as the rest disappeared into the second bend, and by the time I got to it, I could not see anybody.

If this went on, I calculated, I would be lapped at the end of lap three, meaning by the time the race ended I would be three and one third laps down. This could not be happening.

Something had to be done, and that something was to floor the unyielding throttle pedal. This involved bracing my back against the seat while stretching my right foot to the maximum.

This caused my right butt-cheek to lift off the seat, meaning I did the rest of the race practically standing up, not sitting. On a bloody go-kart. But at least I got results.

The unusual driving position I adopted and my overzealous cornering speeds saw me reel in number three within the next two laps, and the blue flag went up again.

Move over. I was now up into third position. My lower back was numb, I had lost all feeling in my right thigh, my right foot was aching, my forearms felt like they were covered in angry wasps, the heat in my jacket was oppressive, as it was in my helmet, and the mandatory shower cap underneath it was sticking to my forehead while sweat dripped into my eyes.

I pushed on stoically. Long story short, I finished third. The leader was too good, even for my kamikaze antics, while the second placed driver I managed to catch up with, but as I prepared a spectacularly wrathful overtake the chequered flag went up.

Race over. Damn. One more lap, just one more, and I’d have had him.

Anatomy of a go-kart

Go-karts have got to be the most physically intense, pain-inducing pieces of automotive hardware that I have tried so far.

Their speed is low, but this is lost on the driver from the mechanical violence dispensed by the engine, which you have to share cabin space with.

The sense of speed is also warped by the cornering speeds: racing slicks mean plenty of grip so you can do an entire race without touching the brakes even once.

Be careful about exploring the outer reaches of the performance envelope, though: push it hard enough and the tyres will let go, and they don’t slide progressively like in road cars, they simple snap; one minute you are going through a corner like Alonso, and the next you are pirouetting in a bizarre ballerina-dance wondering what the hell went wrong. Catching a tail-slide in a go-kart requires real presence of mind.

Try not to eat too heavily before racing in a kart. The sideways grip generates some g’s that really make you ill at ease.

I had stuffed myself full of half-cooked fish and half a gallon of fruit juice (unknowingly) before racing, and having that mix sloshing around in your stomach as you try your best not to get overtaken is an experience that you do not want to go through.

The whole affair was horrible. I felt battered, abused, violated, and humiliated in the last race when everybody overtook me. Karts are horrid, hateful things.

I hated them so much that I am going to race them again, over and over, on a regular basis. Try kart racing before you die. It is fun.