Automtive maintainence -- Tyres

Tires are the number one aspect of car maintainence. They form the single contact of the car with the road. You can upgrade your brake lines, brake fluid, brake rotors, calipers, pads and discs. You can bleed and bed the brake system. You can stiffen your springs and dampers, lower the car's ride height, change your wheel adjustment and improve the steering mechanism, install stiffer anti-roll bars and brace the chassis. You can turbocharge the engine and swap the motor oil and change for lighter rims and more aerodynamic downforce -- but all of these combined will not be as good as a nice tire. Because the tire is the only contact with the road. If you cannot put all this extra performance down through the tire and against the road -- it is insignificant.

Understand, brakes do not slow down the car or stop it. They slow down the rotation of the tire, and the tire slows down the car. The same goes for acceleration and steering and to a certain degree -- for dampening. Hence, driving on bad tires is like driving with a faulty brake system. In fact, modern brake systems have turned so reliable that they never fail completly, so you always have at least some precent of pressure that can still be sufficient to get home. Tires, on the other hand, wear quickely and can give you the same result you might attribute to a failure of the braking system.

The problem is that the tire's contact patch which is pressed against the road is quite little, quite like a man's footprint. See for yourself: Take two pieces of paper and put them in front and behind a tire. Try and get them closer to one another by sliding them under the tire. At a certain point, the paper sheets will meet resistance untill they could no longer be pressed under the tire. The gap left between them -- is the area in contact with the road. This little patch of rubber, is even smaller because road tires (and most tires used in racing street cars in circuits) have a tread that means that some of the rubber in the area of the patch is not on the ground at all. 

So, this little patch, made of nothing but rubber, has to accelerate us (and keep us in a static speed when cruising in highways), slow us down and stop us, turn us aside and keep the car is the requested direction while resisting the side force, dampen bumps and carry the weight of the car and it's passengers/luggage, sustain pressure, physical forces, bumps and heat, divert water, dirt, snow and other things from the way, give feedback to the driver, etc...That's a lot of effort in a day! For instance, on the wet, the tread of the tire has to clear significant amounts of water which, in highway speeds, can be more than one gallon per second!

I have seen cars that stopped significantly further away in emergency braking tests, spun while braking and/or cornering, were not responsive to driver's inputs, very uncomfortable to drive, and produced bad tire and gas milleage -- all due to bad tires in particular. Tires are involved in more car crashes than any other part of the car -- it's not a stuck gas pedal or faulty brakes that could kill you, it's worn tires! Whether they explode, peel off or simply not stop you fast enough or get you into a slide, tires equall safety and bad tires make the car work against the driver.

Tire Choice

Tire maintainence begins with the choice of the tire. There are differences in qualities of tires. For road drivers, the basic parameter is the manufacturer: It should simply be a tire that is made by a known Manufacturer. Here are some examples: GT-Radial, Continental, Bridgestone, BF-Goodrich, GoodYear, Pirelli, Michelin, Falcen, Toyo, Kumho, Yokohoma, Dunlop, Maxis, and others.

Other aspects of tire choice involve the tire rating and type: Tire rating, like all the data regarding a certain tire, are printed on the sidewall of the tire. They rate Temperature, Traction and Treadwear. Each of them is rated between A (or AA) and C. Treadwear is rated in figures. You should go for anything above C. The "Traction" rating in particular, relates to how well the tire stops on the wet -- which might not offer a good indication for how good it is on the dry, so a tire that has AA traction, might be just as good as one with A or even B -- on the dry. Treadwear states how quickely the tire is being worn. Basically, softer rubber wears out faster, but gives more grip. Therefore, drivers who do not make long trips, can go for tires with relativelly soft rubber that give more grip but less treadwear. Treadwear should never go below 200.

The type of the tire relates to it's function: It can be an all-season tire, a winter tire, a road tire with M + S (mud and snow) rating, snow tire,  ice tire and racing tire. Do not drive in the summer with winter/snow/ice/mud and snow tires and do not drive in snow/ice with allseason/race tires. Do not drive roadcars with race tires. Generally look for anything written on the tire with the word "Performance" on it -- these are normally very good tires. In freezing conditions, look for a sign of a mountain with an ice flake inside it -- stating that the tire is adecuate for heavy snow.

Good tires don't come for free but overall, tires are one of the cheapest car parts and the most important -- so changing them to new tires will actually pay out quickely in terms of milleage and in avoiding collisions. Remember, the tire should come from a known manufacturer, have good ratings and be suitable for the conditions.

So, we have bought new tires, but what about their placement? You have probably heared the rule of  "placing the good tires on the rear." The goal of placing the good pair of tires on the rear is to avoid the car skidding into a situation called oversteer, where the car skids with it's tail and spins around. This happens when the rear wheels have less grip and slide first. So, by placing the good tires on the rear, we avoid oversteer. There is also a school of thought that is for placing the good tires in front -- mainly because that's where the bigger brakes are. 

Our advice is simple: The good tires go...ON ALL FOUR WHEELS. If there is a doubt as to where to place a new pair of tires, this means that at least two tires are already worn to a point where still riding on them is perillous. When you have such a doubt, now is the time to replace all four tires. This way you get both a stable car that does not oversteer, and also good braking -- and not for a significant change in the amount of money spent.

Tire Replacment

By now we have covered the subjects of purchasing new tires and placing them on the car's wheels. But, there is more to it. First, we begin with when to REPLACE tires. There are several criteria, and since tires are both relativelly cheap and very crucial for safety and performance, we should be strict and if any single one of these criteria is present -- we should replace tires:

- If the tire appears significantly worn, damaged or dry -- we should replace it (no matter how much it has travelled or how old it is). Before every drive, take a few second, to look at the tires and search for cracks and damages.

- If the tire has did a sum of 70,000km, it's time to replace it. Even if it still looks good and new, and even if it is still new -- this tire has probably lost over 50% of it's abilities.

- It the tire has passed the age of three years -- it should be replaced. No matter how much miles it did (even if it wasn't used at all) or how good the tire appears to the naked eye -- the rubber undergoes a process of expanding and shrinking under weather changes and it also dries out -- making the tire lose some 20% of it's qualities already when just two years old, and about 50-60% when three years old.

- Tire Tread Depth: With all but Slick racing tires, the tires should have a deep tread for any moist the tire might come in contact with. The popular penny test indicates that the tread depth is larger than 1.7, which is just above the legal minimum of many countries. A safety criteria is a minimum of 3 mm.

A tire's age is determinded based on the date that appears on the tire. It is the only date that in printed INTO the rubber. It usually consists of a letter, and than four figures. For instance, 2610 -- which stands for the 26th week of the year 2010. 1709 stands for a tire that was "born" in the 17th week of 2009.

Tire inflation

Now we reach the most complex subject of all of these, and none-the-less important than the above: Tire air pressure. Tire pressure is measured at PSIG or BAR. I will use the PSIG measurements I'm used to. They represent the pressure created by the amount of air which is squeezed into a tire. More air results in more pressure and less air -- in less pressure. When referring to tire pressure, it's important not to associate it to baloons. In the tire, air pressure has a much more crucial structural role: More air means a stiffer tire and less air means a softer tire.

If you remember, I previously mentioned that tires made of softer rubber have more grip but wear out sooner. But, when we look at the tire as whole, things are bit different. The side force generated when turning the car works on the tire, distorting it somewhat. A stiffer tire resists the side force and distorts less and can provide more grip and less wear. That's why the fear of the tire exploding if we overinflate it is not justified -- unless the tire is extremlly overinflated.

Tire pressure also changes the shape of the tire. Many people believe that less pressure will make the tire scrubb against the ground which means more rubber against the tarmac which means more grip. This is not a true assertion. Why? Because it is made based on looking on the tire from the outside. If we could look on the tire from below (say, if the tarmac was transperent), we could see that -- because less air means that the tire is softer and flexes more -- it is pressed agains the surface but it also flexs and folds so that the center of the tread -- where most grip comes from -- is folded and lifted from the surface. This is catastrophic for grip, tire wear and especially for braking. 

On the contrary, overfinlation below the "right" pressure, results in the opposite. The tire, which recieves a convex shape when underinflated, is now rendered into a concave shape, which makes it grip the road with the center of the tread, and not so much with the shoulders of the tire (corners of the tread). This is better because the center of the tread is both more durable and more grippy, and also in adverse conditions because this kind of tire tends to penetrate through water, snow, mud, gravel and whatever might cover the road surface, and find grip below. If in doubt, overinflation is better than underinflation!

Note: Many people believe that off-road drivers tend to underinflate their tires. They do not! In off-roading, underinflation is used in very specific situations, like deep mud or dune driving (driving on loose, dry sand). In this case, the convex shape of the tire captures sand inside it which gives it more grip. In shallow mud, mould and alike -- the underinflated tire will capture the mould of mud in it's folds -- which would make it slide over them rather than grip the more grippy earth beneath them.

But, why should there be any doubts regarding tire inflation? After all, the manufacturer states clearly how much pressure to put in each tire. This is all very true, but some variants change the pressure:

1. Heat: After driving on tires to the gas station, the tire sometimes heats-up considerably. If you feel noticeable warmth when you touch the tire's sidewall -- it is hot and the air inside it has been expanded by the heat. Say that the pressure in the tire before you started to drive was 30PSI. In the station you might reach a measurement of 33PSI. Now, let's say the tire is undefinflated and only has 26PSI, at the station this might appear as 28PSI, and you will have to inflate it to 33PSI instead of 30. This is another advantage of overinflation -- you can always bleed out the excessive air later.

2. Load: Three healthy adult passengers in the back seat increase the weight of the car significantly. For such cases, you will find that the manufacturer specified different figures for inflating the tires when the car is loaded. Inflating tires with more pressure for a loaded car is something most people fail to do, but it is very important, especially in long trips, and it severly reduces the grip of the loaded vehicle.

3. Performance: In racing, you deduct the correct pressure in the practice sessions. After a few laps, you check the tires for wear and temperature. If underinflated, the contact with the road will be in the tire's shoulder, so it will be more hot and mor worn. If overfinflated, the heat and wear would be more evident in the center of the tread.

4. Accuracy of the check: Different guages give readings in different accuracy. The least accurate kind was/is used in old gas stations where the you aim the pressure you want with by rotating a dail. These pumps should never be trusted (they can mislead you by more than 10 PSI!). Most modern gas stations have digital guages that are more accurate, but it's still advisable to use a personal guage. Pencil guages are the least accurate type of personal guage, but they are cheap, easy to carry around and resistant to blows -- so they are my choice. 

Digital guages are more accurate and some dail guages are even more accurate -- but the differences here are very slim and these guages are cost more, harder to carry around, and can be knocked out of callibration by a blow without you even knowing about it. A pencil guage will mislead you by a maximum of 0.6 of a PSIG.

The frequency in which we need to check air pressure is in times considered as once a month. But this is too much. It's best to check once every two weeks. This way, there is no need for dramatic inflation, and the whole procedure takes a few seconds, faster the fueling the car. Remember to put the caps back on the air nuzzle once done!

If we rate the different parameters of a tire, the most important is wear, than comes milleage, age, tire quality and tire inflation, but the differences are not very significant.

Front tire failure

If one of your front tires do fail and blow-off when you drive, it's important not to panic. You can still control the car.  Slow down steadily and keep on steering the car carefully at a low speed. Some states in America and Europe have special stop-zones alongside the road where you can stop. If the road does not have such a stopping point -- DO NOT STOP ON THE SHOULDER OF THE HIGHWAY. The risk is like nothing you ever experienced. Get on the shoulder and drive slowely enough so that no significant damage be caused to the rim, untill you reach a safe place to stop. The risk exists even if the blown tire is on the side of the car which is not facing the road.

Rear tire failure

This can cause a spin-out that is usually beyond the ability of the driver to control. The choice is to brake really hard to stop the spin, and try and get to car slowely to a safe stopping zone.

Driving Styles and changes in Technique

As you have probably witnessed by now, effective driving on the road or track, is based largely on proper technique. In particular, race driving in a track revolves around the ability of the driver to perform ideally in the ideal technique. Without enough seat time, reading the theory of these techniques can create a mirage that developing a driving style is performance limiting.  After all, on a track, we need to strive to be driving at100% of perfection, which does not leave much room for different style, right?

But, saying this is merely a result of not having enough seat time.  The seat time makes the driver aware of the difference between theory and practice, between our current reality and the desired outcome. The seemingly slim but surprisngly large gap marked in the word "striving to perfection". 

Racing Spartanism

Activities of popular sport have created the illusion amongst ameatures, that in any sport -- and motorsport not being an exception -- the participants rely solely on their skill. So many enthusiasts with basic awareness to vehicle handling, are under the false belief that race-cars are set to oversteer so that they could turn really well. They fail to understand that all racing drivers are in fact just people. There are very well-defined bounderies as to what they cannot do. No driver, not me, not you, not Michael Schumacher, Sebastian Loeb, Colin Mc'Rae or Ayrton Senna -- none of the above can:

- Enter a corner fast (fast as in -- above the maximal corner speed)

- Control sudden oversteer when driving the limit at full speed on the track.

With all do respect for skill, it is not the only thing drivers, even expert drivers, rely on. No driver (except for Colin Mc'Rae) would trust solely on his skill to drive a car that naturally oversteers. Yes, they might manage to drive it, but they prefer not to. They adjust their cars with some minimal understeer, for reasons of efficiency, but also for some safety and consistency. Do not confuse these with either fear or hesitation. A driver that adjusts his car so that his consistenty and safety rely solely on his skill -- should never set-up cars!

Another example is the point of Skid Recovery. I have already expressed myself again short tuitions that pretend to teach a driver about Skid Recovery. It is a fragile and problematic field: Average drivers cannot acquire true skid recovery skills, but expert race drivers also find themselves lacking the need to apply it: Either they avoid it, or otherwise they find themselves reaching a state of skidding at a speed and pace that do not allow to recover. Skid recovery is a practice mainly for drivers in the broad midrange of skill, and even than -- prevention preceeds correction.

Furthermore, it's easier to learn how to slide than it is not to slide. Many drivers find it easier to have the rear wheels turn them into the corner and use the front wheels as a "stability control" of some sort. It also gives a sense of fast driving through the feeling of the jerky car and the constant application of steering inputs. In a certain way, this is what rally drivers do on gravel -- the slide not to reduce safety, they slide to increase it. If you drive the limit, any small mistake leads to a sudden, sharp breakaway of the car at speed. If you drive within the limit, intentionally provoce the car into a slide and control it through the slide, you will remove the element of surprise because the slide is intentional and you will get a more controlled slide because the speed and pace in which you initiated the slide are reduced.

To quote Ross Bentley: "The most succesfull racers of all time, people such as Jackie Stewart, Alian Prost, Al Unser, Rick Mears, Richard Petty and Dale Earnhardt all have one thing in common -- they finish races...Never forget: "In order to finish First, first you have to finish." In racing, playing safe is playing smart and playing smart is driving faster. 

In fact, if you remember my modell of Effective Driving -- where Safety is just one of the byproducts of good driving habits, the above statement still hold true. Even though the goal of effective driving is to give you not just safety, but also milleage, comfort, etc. I always stress those benefits because I don't like it when certain people neglect them by talking just about safety and/or speed. Still, I have to agree that safety is the main concern: If you concern mainly or largley about things like comfort or milleage, than you live in an illusion of safety -- and you think you are safer than what you really are. Safety is your number one concern, period.

Professional Training

I believe that, in a certain way, the popularity of motorsport (or any other sport) stands in contradiction to the level of professionalism amongst begginers: In the US and in several regions of Europe and the UK, track days have become so accessible that driving around a track has been degraded from the prestigious status it once held. By itself, there is no problem with this. In fact, it could have been great. The problem begins with groups of people in different levels of skill -- which are "autodeducted" drivers.

Driving is an activity with very strong psychological aspects relating to one's independence and freedom. We, as drivers, thus search for autonomous improvement: We want to get better on our own and we admire those who we think have succeded in that path. Psychologically, a driver that "grew up" himself as either a road driver or a race-driver, gives the same impression as modern buisness man that came from a poor family and made himself into what he is today. 

My point is to challenge this school of thought. The basis of this way of thinking is that we favor innovation -- we like making NEW things, we like doing things differently than we were taught. However, maybe imitation -- following the lead of a person that has earned our respect and appreciation -- is not so bad. Maybe it's even honorable for people to follow the lead of those who they themselves deem as "professionals"? Well, if you ask an anthropologist, he will tell you that whether you judge imitation to be worthy or not, it is very widespread. Much more common than most people believe. The fact is that most human actions and decisions are made based on imitation and not based on someone's personal ideas and judgement. Many historical cultures, some of which are considered to be very glorious, attributed imitation with a high degree of respect. Only our culture, the modern culture, has started to question imitation and favor innovation instead. Over the human history, we are the exclusion and the exception, not the "normal" people.

Furthermore, this modern perception has little effect on the actual reality. Relating to driving and motorsport as a part of the field of sports, we can safely say that people get into the world of professional sports and advance therein, through some training with instructors, coaches or whatever you would call them. They provide a third-party point of view which is crucial at initial stages and maintains it's significance as the student improves. You cannot teach yourself Tennis, Swimming or performance driving. Well, you CAN do it, but the result might not be very good.

The problem is that without professional observation and training, the driver is not likely to even distinct "good" from "bad". He might do something very badly, or at least not as good as he can do it, and not being aware of it. A driver simply cannot measure success by himself. It's not that he nessecarily won't succedd, but if we define success as a goal, we want as much of it as possible. As I say, we don't want to go FAST, we want to go FASTER. Even competing race-car drivers can spend a career of driving with several basic technical mistakes in their driving style. For something to "work" does not mean it's working as efficiently as possible.

What I'm getting at, is that there is no lost in dignity when someone turns for a trainer to work with him on improving his driving, and there is not lack of dignity in taking procautions, even on the most competitive track enviornment.

Vehicle as a Varient of Technique
The question is whether other cars demand another technique. The short answer is yes. The basics of effective driving are/should be shared by all drivers in any enviornment/car. In the level of a personal driving style, the car carries a considerable change, in terms of driveline, weight distribution and suspension geometry which have an impact on the variant of DRIVABILITY.

Drivability is the criteria for how well a car drives. Unlike the question of how much grip or power it has, drivability is largly subjective. Certain cars benefit from drivability which is better in certain respects over cars which are superior in different aspects of drivability. One car might handle with greater obedience to the driver, but another might have superior communication with the driver.

Some cars demand more accuracy, some demand more smoothness, some demand more decisiveness. Some cars demand more input through the throttle/brakes and are literally driven with the feet, other cars might have a balanced that is slightly more inclined towards control through the steering wheel and the driver's hands. A driving style, whether in relation to a different car or a different person, is not in the big picture (and is therefore not crucial for performance). It's about the perception, it's inside the driver's head: it's where he places the stress. It's a manner of perspective: Let's say that an effective turn-in requires turning the wheel at a certain timing and pace. One driver might view it as being a relativelly "quick" turning of the wheel, while another driver might turn the wheel just as quickely and relate to it as being "slow" and "smooth" relative to something.

Driver as a variant of performance
A known American driving trainer, named Peter Krause, has a saying: ""The driver is the greatest performance variable in the high performance driving equation"." If there is a thing that can be said with certainty in the field of racing, it's this saying. Driving skill and good driving techniques (which are adopted by training with a trainer) are better than any car improvement. A bad driver will mess the ride in the best cars. In fact, the rule states that the faster the car, the slower is it's driver. Performance cars, and especially professional racecars, are very hard for ameatures to drive and will not see mistakes kindly.

In French Racetracks, the local instructors often have the tradition of taking students between sessions to a lap of the track with a Van. The point of such a lap is to allow to carefully inspect parts of the track that are hard for the students, by driving the track more slowely, but it also has anoter purpose: To show that car control and effective driving at speed are possible in every car -- all that has to be changed is the driver's attitude. This brings us back to driveability: Some cars are more difficult to drive effectivelly, but can be more rewarding, some cars are easy to drive fast, but can be less rewarding, and some are both easy to drive and rewarding. I have witnessed very impressive car control skills practiced in vans, trucks, trailers, old roadcars, etc.

Still, there are other levels to be considered:

1. The car: Like I said, racecars should be adjusted or performance, but allow for a certain margin of error. If you don't give yourself that extra safety gap, you are not going to be driving fast. In fact, you risk the chance of not being able to drive further at all.  Likewise, driving skill should never be used as an excuse to drive in a badly-maintained vehicle. A good driver only drives on a car that let's him drive effectivelly. If the car has worn or old tires, it will work against the driver.

2. The road: My point that limiting performance to allow for a margin of safety is legitimate, is tenfold more important on a busy or slippery track, or in places of high speed, small runoff areas and surely on the public road. Trusting solely on your skill to keep you safe while not paying attention to the changing conditions is simply dumb. We are humans. Humans naturally make mistakes. Know your limits, on the track and off of it. Even on the track, in order to drive fast, you need to know WHERE and WHEN you can drive fast. The Nurburgring is a place where a "smart" driving style pays off. The Nurburgring is not a racetrack, it is a ROAD, and has the safety runoff areas of a road. There are various areas and situations where you CANNOT drive fast.

3. The road users: They can be related to as part of the road. This is especially beneficial in competition, but less beneficial on the road where other road users interact with you. For an example, we know that the winter and rain present hazards for us, but other than being more dangerous and difficult to us, do we consider how much more difficult is it for the other road drivers? Think, other road users are probably as challenged as you, making them less likely to notice you, maintain the nessecary safety gap from you, etc.

Getting back to Driving Styles

So, one driver turns the wheel more sharply, another turns it with a stronger stress on finesse, without either of them being just balanced as they should be. However, before criticising them, understand the torment of sports -- no matter how much you constantly strive to perfection, perfection is not hard to achieve, it's impossible to achieve. The idea is to get as close to it as possible, which can be done in several ways and from several directions. The differences appear slim to the ameature, but mean a lot to the experienced. The only way to discern them is to have practical experience and, based on what I said before, such an experienced better be with a trainer. 

N. B. If you like conspiracies and you believe that I'm cynical and all I want is to get money out of you -- you can be certain that I'm not instructing driving anywhere near you, so I have absolutly no financial gain from what I write about driver's training. I simply believe in it, as a trainer and as a student.

The Skid and How to correct it/ Ross Bentley

Most skids, spins or out of control situations are a result of loss of concentration, driving beyond the limit (too fast), or a simple mistake (which usually upsets the balance and traction of the car). Getting into this kind of trouble is quite easy, especially in adverse weather conditions. And getting out of it can be easy with a little knowledge, some thought and experience.

Skid control is never easy. It is one of the most complex aspects of car control there are. It is in fact a self-contradiction: Skid-Control involves regaining control that has been lost. Knowledge and thought are always good, but during a skid, they are near completely useless. I have seen drivers who have just been practically beaten for a hour with knowledge regarding oversteer, what to do and what not to do: They set out to the SkidCar. It's not their car, there are no obstacles in sight, only open area of endless grippy tarmac, the driving speed is slow, the driver is in a “triggered” state of mind, and with a personal instructor in control besides him.

These people sit in the car, think well about what they are going to do and what they really don't want to do. They set out and...do it. Or at least, they think they did. Recap: They were told to do (a) and not to do (b). They set out, thinking very well on doing (a) and not doing (b), set out, do (b) and think that they did (a). They spend some time argue with the instructors that they did (a), try again, and the same ordeal repeats itself two-three more times. Only after that, does the driver begin to apply corrective input with some efficiency.

Now, let's move fast-forward ten months. The driver has a new car with different handling characteristics, he is driving a wet, bumpy road at dark in a speed of 50mph, alone. The car breaks loose suddenly, would he be able to mimic his still crippled level of performance at the course a year-past?

To teach skid-control to a sufficient level of skill, it would take:

1. Knowing all of the basics of car control – understanding grip, car dynamics, drivetrains and engine layouts, being aware of changes in the coefficient of friction as road conditions vary, knowing how steer, where to look and how, etc. Trying to teach or even simply portray oversteer control in an article – when isolated from these other skills – is foolish at best.

2. Acquiring the aformentioned knowledge not through articles and not via trail and error, and not even in a Skidpan tuition. It takes a special, three-four day-long course for advanced driving and car control, or a dedicated skid-control tuition at the length of seven hours at least! In both cases, the instruction must be professional and based on practice on a special simulator (SkidCar device) and a follow-up drill performed in the driver's personal car, on dry and wet tarmac, and on tight gravel. Skidpan tuitions, where they use low-friction surfaces and inclines to induce the slide, are very ineffective.

Even with (1) and (2) done, the chance for a corrective input in real time to be effective rests between 30-40 precent, and a bad, inaccurate or untimed corrective input will make matters much worst than they would have been if the driver would let the car skid to a stop or brake to a halt.

For the car to suddenly “break away” and the driver recovering from it effectivelly, is none-existant. A driver that really knows how to recover from a skid, will either avoid it or know when it is going to occur, so it's not a surprise. He knows all of the variables that can change the corrective input required: Torque, grip, setup (front to rear grip levels), driveline (rear, front, etc), tranny, cause, existance of electronic controls, skill level and qualifications, speed, even the seat! If a driver reaches a situation where his car suddenly breaks away, he might manage to recover with luck, but he will never manage to perform an accurate, effective solution.

Unfortunately, skid control practice is difficult to come by - you certainly don't want to have to do it in everyday driving! Practice and experience it only in a safe environment.

One of the most common types of skids you may face is when the rear end slides out on you - the oversteer skid. What do you do? FIRST, STAY OFF THE BRAKES! If you touch them you will make matters worse. By braking, you transfer weight forward (the car nose-dives under braking) reducing rear tire traction and most likely causing the car to spin out completely. Instead, JUST LOOK AND STEER WHERE YOU WANT TO GO - this will automatically make you steer in the direction of the skid. In other words, in the direction the rear end is sliding (this is called "opposite lock"). And sometimes, very gently increase the throttle to cause a slight weight transfer to the rear, which increases the rear tire traction. I say sometimes because giving it more throttle may make things even worse. Think about it. What got you into the problem in the first place? Usually, too much speed. The last thing in the world you need now is more speed.

Completely wrong, and for various reasons. First, oversteer is the least common type of skid! ALL cars are set to do the opposite and UNDERSTEER, because oversteer is far too complex for the average road driver! Also, oversteer is not defined as “the rear end sliding on you”. Certain combinations of coarse handling and car setup can result in the car swaying laterally without breaking traction to the rear in particular. This would not be considered as oversteer! Oversteer is defined a rear slip angle larger than the front slip angle.

Second, while it is true that “touching” the brakes “make matters a lot worst”, The average road driver – including one who is a veteren of a single skidpad tuition – will do well by STAMPING on the brakes forcifully and than declutch while straightening the steering. Yes, this will shift weight to the front and off of the rear, but it will also result in two other effects. First, a dramatic lost of speed, and an exponential reduction of the Centripetal force and Angular Momentum that is sliding the car. Also, if the car stops, the skid stops and, if you do hit something, you are likely to just brush it at 8mph instead of crushing into it at 40mph.

Also, braking hard locks up all four wheels, at least momentarily. This makes them slide in the direction in which the moment of inertia is pushing the car. This, along with the reduction of speed, can straighten the car back up.

Furthermore, even when a driver is skilled enough to control oversteer, he should never do it in the prescribed method. It might sound great, but in reality it's much more complicated. Like I have said, there are no magic solutions for a situation like oversteer, and that includes “looking and steering”. What have you basically done by steering like this? Have you removed the cause of the skid? No!

Of course, the cause of the skid cannot be known before the author be kind enough to detail it, but I will tell you of two reasons:

1. In a powerfull rear-wheel drive car (and some four-wheel drive cars), when the driver over-powers the rear wheels with torque by giving it too much throttle.
2. In all drives, by suddenly throwing the car's weight forward by sudden braking or even an aggressive lift off of the throttle, mid corner. Both cases are different and require different inputs. The type of the drivetrain also carries great importance, as well as the existance of electronic software like traction control, the given amout of torque, the amount of grip, the speed, the angle of the skid, etc.

So, you probably understand by now that this is a complicated subject, much more complicated than this article presents it. That's the problem: Presenting a deep and complex subject with extreme simplicity, pretending to teach in writing what can only be taught via an intensive, orginised training program – all without even thinking about the wide audience of drivers (at different levels of skill or understanding of car control), the driving enviornments they deal with, and whether they did understand the article or not (which someone can make sure when he is instructing a student face to-face).

Still, for the sake of disscussion, I want to try and get you to understand the subject better. Of the two different inputs the author stated: The steering and the throttle, it would appear that steering takes priority and throttle is of a lesser importance or perhaps even optional. In reality, it goes the other way around.

If we get oversteer by too much torque applied on the rear wheels, we must reduce the amount of torque applied by...reducing the throttle input. However, usually we should avoid lifting-off completely to avoid a forward weight transfer. Also, with the case of oversteer caused by such a forward weight transfer, we would have to shift the weight forward...by accelerating!

That's what makes oversteer so catchy: Do you have the Huevos Grandes required to accelerate when the car attempts a spin at a high speed (or at least, avoid jerking off of the gas)? For the sake of dissscussion, let's say you did somehow get on the gas, do you have the skill and knowledge to judge the right amount of throttle, plus the nessecary steering correction, in just the right moment?

Remember, the throttle can overpower the driven rear wheels. Even in a front-wheel drive car, the increase of speed might make matters worst (like the author stated), especially when the driver applies too much, too late or does not make any steering correction while operating the throttle. It can also make the front lose grip and get the whole car sliding away from you.

In another article on this subject, referring to the differences between the driveline configuration and it's effect on driving style, Bentley said:

"You often hear people give the advice “accelerate hard in a turn with a front-wheel-drive car to ‘pull’ you out of a skid or slide”. Think about it. If the front tires are at or near their limit of traction, and you accelerate hard, all you are going to do is increase the understeer. Again, the tires have a limit. Respect that limit.” (Ross Bentley, “Different cars, Different techniques?”)

This conclusion of Bentley is right when referring to understeer. However, regarding oversteer, he is plain out wrong! Yes, the front wheels have a limit, so you increase it by taking the steering input out (straightening the wheel) and accelerate with feel. Also, even if the tires do spin somewhat, since the accelerator is usually the weakest car control, you are able to spin the front wheels but still get the weight transferred to the rear. This is GOOD, because the spinning front wheels get pushed away and straighten the car back up.

However, remember, even one hand on the wheel has more control than two feet would have, and two hands on one steering wheel have tenfold the control and authority than one foot (right foot) operating two pedals (throttle and brakes). A throttle correction is complex!

However, a steering-alone correction, as suggested by the author, is much worst. Run the scene at 100mph. How much steering would the driver have to apply and how quickely, to get the car under his control, and how quickely would he have to remove that input to avoid being thrown the other way? Furthermore, there is a difference between “catching” the slide and “recovering” from it. By steering the car, you try to keep the front wheels rolling naturally while making the turning radius wider.

When applied with skill, this can be enough to stop the car from spinning, but not from sliding. The driver will find himself obligated to turn the wheel more and more until he reaches full opposite lock, and than wait for the car to wipe off speed, hoping it would run out of speed before it runs out of road, which sadly tends to occur earlier. Than, the side-swipe would spin the car around only to suffer a second blow from the rail.

Furthermore, turning the wheel reduces overall traction and can make the situation worst by generating drag that shifts more weight to the front, or by reducing the amount of the traction that can be used to accelerate the car and pull it from the oversteer.

I understand from where the author concluded this manner of response to be right. If you drive on good grippy tarmac, at moderate speed, in a weak Rear-Wheel Drive car without a particularly light back-end, power oversteer and oversteer caused by braking in a bend, can be resolved in a sufficient manner by simply letting go of the pedals and steering: “If in doubt, both feet out”. However, take most cars in most conditions, and this correction is less effective, particularly if you dial in normal driver's response times. Even with cars where it might be tolerated, it's dangerous to categorily instruct this manner of recovery because you inherit bad habits that you will later apply in the wrong car/situation.

Once you catch the first slide or skid, be ready for one in the opposite direction caused by over-correcting. If it happens, gently correct for it by looking where you want to go and smoothly try to ease the speed down until you get the car under control again.

As the author described it: Steering where you want to go and than perhaps adding some throttle, what will happen is that the driver will compensate with a certain amount of countersteering, and as he accelerates, the car would suddenly re-grip with the front wheels turned against the corner.

This results in a pendulum effect that makes the moment of inertia toss the whole car ever more violently to the other way, and an increase of speed with the throttle only makes it worst. Besides being physically more severe, the pendulum skid is harder to recover from, because it's sharper and the driver has to remove the steering input and start steering sharply towards the other way in a rush. Also, with the origina slide, the car spins but often stops relatively close to where it started. With the pendulum skid, the whole car (not just the tail this time!) is immediately pointed towards the outside of the corner, leading to a roll-over off of the road or a head-on collision with a car in the opposite lane.

If you experience an understeer skid, with the front end sliding or plowing towards the outside of the turn, the correction is simple. Just ease off the throttle, which transfers more weight onto the front tires giving them more traction, AND STRAIGHTEN THE STEERING OUT SLIGHTLY. Most peoples' first reaction when faced with this type of skid is to turn the steering wheel more and more. But, this increases the problem because the tires were never designed to attack the road at an extreme angle. Tires were meant to face the road with their full profile, not with the sidewall, so their traction limit has actually been decreased. So, decrease the steering input slightly and ease off the throttle gently to allow the front tires to regain their grip, and then begin to steer again.

This paragraph is better but it stands in contradiction to the former. The author says not to “force” the car with the steering when experiencing understeer, so why does he recommend just that during oversteer? It's just the same: You try to “force” the car with the steering, but it does not respond, and you simply keep on putting more and more steering, run out of steering and than it's a question of what you run out of first: The speed or the road...

However, since understeer is recovered from by decelerating, steering more to make the car slide MORE and decelerate more, can sometimes be quite effective. This is why understeer is the preferred situation for the unskilled – it solves itself, and is tolerant to steering-based corrections.

Certain car designs lead to certain handling, and therefore skidding, characteristics. Most cars with a large percentage of the weight over the front wheels (front-wheel-drive cars or rear-wheel-drive cars with heavy engines mounted up front) tend to understeer at the limit. Cars with a large percentage of weight biased towards the rear (mostly mid-and rear-engine cars) tend to oversteer naturally. This is mostly caused by a pendulum effect the weight has on the heavy end of the car. If you quickly try to change direction (as in turning into a corner) in a naturally understeering car, the weight of the front end wants to keep going in a straight line causing the car to plow. In a mid- or rear-engine car, if you lift off the throttle in the middle of a corner (causing weight to transfer off the rear tires, reducing traction and making the car oversteer), the weight of the engine works like a pendulum swinging out and trying to spin the car (“trailing throttle oversteer”).

NO road or race car oversteers naturally. Only few car used in rallycrossing and drifting have natural oversteer and very few rally cars have neutral handling. Otherwise, any car would have some degrees of understeer. Drive it on a plain road of tarmac, maintain a constant speed with throttle and turn the wheel without any Appel Contre-Appel provocation, will it spin? No. So it does not naturally oversteer. Even if you try to turn the wheel more ubruptly, you are likely to aggrevate the understeer or cause the car to “cynical-steer”, it feels like oversteer but it isn't.

As you can see, weight transfer has a great influence on how your car behaves in a skid or slide. Smoothly controlling that weight transfer is the real key to skid control.

If the car begins to oversteer skid and you can't control it as described above, you are going to spin-out. Nothing wrong with that, if you keep your cool, watch where you are going, de-clutch and lock up the brakes - and hopefully don't hit anything. Remember these words, “spin – both feet in”, meaning left foot on the clutch and right foot on the brakes. That is all you can do - besides avoiding the spin in the first place.

Correction: The clutch goes AFTER the brakes, so you have some support with your left foot as you right foot stamps on the brakes. Unless the driver is very skilled, this is the sole manner of performing a sudden stop (no attempt of threshold braking) and the only way to recover from oversteer (no attempt to correct it).

Ross Bentley, Senior Instructor, Driving Unlimited

Professional Race Driver

“But it's Ross Bentley, surely he cannot be wrong?” Well, it's either him or: Chris Harris, Martin Rowe, Tim Harwey, Tiff Needell, Jason Plato, Tommy Makinen, Danny Glatter, O'n Ya'akobson, Lior Levi, Itay Alon, Colin Mc'Rae, and many others. Either they are all wrong, or Ross Bentley is right. I doubt it.

Driver's enviornment -- Seat, Steering, Mirrors

Our first Driving rule, on the track and road, is to set a safe enviornment before we drive. The driver's envionrnment is very important because it serves as a "homebase" for good car control. Once you have that set, you can keep you focus outside the car and far ahead. The enviornment should give us both comfort and passive/active safety. Generally, the three do not conflict. Comfort is different from convenience, because the latter can be achieved mentally via habit. Comfort is predominantly physical: Good ergonomics.

If you suddenly ask someone to go with you to a place about one hour of a drive away and he refuses because it's "too far", that can relate to his driving enviornment. He might not feel physically comfortable to drive for a full hour, and this effects his mentality. Active safety refers to the ability of the driver to see and react to the hazards on the road. Slow reaction times and large blind spots in the mirrors are major causes of collisions that stem from a bad setup of the driver's enviornment. Passive safety revolves around the damage inflicted to a person's body during a crash that has occurred or even when driving over a large bump.

The seat

1. The Seating:
If the seat is positioned, but the driver is not positioned well inside the seat, that's a problem. So, don't sit ON the seat, sit  IN it. Sit upright and push your back and buttocks as tight as possible into the backrest. Sit straight up and down, don't lean sideways. Your legs should also be positioned so that they are as apart from one another as feels comfortable. Most people in most cars can actually lean their knees against the walls of the pedal cluster, on the center console and the doorskin.

2. The seat height:
Adjust so that there is a distance of a handwidth (five fingers) from the ceiling. In convertibles, set it so that the open visor does not obstruct your view. If in doubt, too high is better than too low. A race-car requires lower seating for more stability and feel, particularly a drifting car.

3. The Seat distance:
Adjust according to the pedals. When pressing on the pedals, the pressure should be applied from the balls of your feet, not the toes. The heels belong on the floor and the movement of the right foot from throttle to brake could usually be done by pivoting over the heel.
Place your right foot on the brakes and the left foot on the clutch. In an automatic, the left foot rests on the dead-pedal to the left. Start the engine, press with the left foot unto the clutch or against the footrest. Press on  the brakes a couple of times with your right foot and than squeeze it down. With both feet fully depressing the pedals, the knees should be bent at about 120 degrees.

If the angle is closer to 90 degrees and the knees are crammed, you are too close. If the knee is boltstraight, you are too far back. When in doubt, too close is better than two far. Boltstraight limbs are tiring, lack sensitivity and can suffer from fractures.

4. The Backrest angle:
Adjust according to the steering wheel. Stretch both hands forward and place your wrists directly ontop of the wheel. You should be able to just slightly bend your wrist over the rim. The goal is to manage and do this without hounching your shoulderblades forward.

5. The Steering distance:
Grip the wheel at 9 and 3. Your palms should be placed on the outside of the rim and the thumbs can be hooked over the crossbrace unless it feels uncomfortable or if driving off-road. Grip the wheel lightly, feel it mainly through your fingertips, not just the palms or thumbs.

Adjust the distance of the wheel so that you can perform stage (4) without houncing any part of your shoulder forward and with a slight bend in your elbow, all without erecting the backrest to 90 degrees. You should avoid placing the hub of the wheel closer than 25cm from your chest. Place your hands on the wheel at 9 and 3 (both sides), the elbows should be bent at about 120 degrees. Too close is better than too far.

6. The Steering height:
Adjust according to the height of your shoulders. The palms at 9 and 3 should be just slightly lower than the shoulders, about 5cm. Too low is better than too high.

7. Head-Restraints:
Headrestraints are terribly overlooked. They are crucial for avoiding a dangerous whiplash. Adjust it to a height where it is in line with your eye-browes (if in doubt, too high is better than too low) and most importantly, so that your crumped fist cannot be placed between your upright head and it. New cars have highly adjustable restraints that can be adjusted for comfort and safety equally.

8. Seatbelts
Seatbelts are most important, no upright seating, low seat position, safety seat, airbag or head restraint can even be close to replacing it. There is more to it than just buckling it up. Pull it slightly to tighten it around your waist. If adjustable, set it's height to fit unto your collar bone (shoulder) and not on your arm or neck. If in doubt, too low is better than too high.


9. Windows:
Always keep one of the windows slightly open. In the summer, it helps keep the compartment ventilated when air circulation is activated. In the winter, it helps keeping fresh air incoming. In the city, where fully open windows can replace using the A/C, prefer them open. On the highway, avoid having a window opened more than that little gap ontop, as it increases fuell consumption due to drag. Avoid keeping a window halfway open and do not place hands on or beyond open windows.

10. Air Conditioner
Internal circulation is usually better than external air circulation, as it blows more air. When you need to cool a car that stood in the sun, internal circulation works best unless the car is very hot, but it's preferred to use external circulation to filter out pollution from the plastic within the car. When cleaning fumes from the glasses, circulation can also work, but most cars work better with external circulation.

11. Glasses
Keep all glasses: Windows, mirrors, lights -- clear. This allows to see better, illuminate the road better and suffer from less glare.

12. Interior mirror
The mirrors are adjusted without moving your head from it's straight forward position.

The interior mirror should be set to get just the rear window, that's it. Any aftermarket mirror designed to show you more, or any attempt to use the mirror to see what's going on inside the car, are bad and hazardous. Clear any obstruction you can from it's way and tilt the little switch under it into "night mode". This way, you will not suffer from glare through that mirror and you will be able to get a clear image.

If you want to see what happens in the rear seats, buy a small additional mirror that sticks unto the windshield with vaccum taping. Place it to not interfere with your peripheral vision or with any of the visors.

13. Driver's side mirror
In the US, for the sake of disscussion, the (left) driver's side mirror is bigger for both European or American-made cars, than the right, passenger side mirror. When the opposite holds true, the adjustment is reversed. Place an assistant about 3 feet behind and tell him to move to the left untill he is about to dissappear completly from the interior mirror. Now, open the left mirror untill you just bearly see part of him in it.

Now, the mirror is opened to the minimal amount of overlap with the interior mirror. Normally, with this adjustment, you will not be able to see the edge of your own car in the mirror. Move your head towards the glass untill you see it. Memorize how much you needed to move your head to see that tiny bit of silver in the mirror. In most European cars it takes just the slightest movement of the head. In most American cars you get the head all the way against the glass. In some cars it's somewhere in between. This way, you know next time how to adjust/check the adjustment of the mirror quickley by yourslef.

14. Passenger side mirror
In countries where you drive on the right, in American or European cars, this mirror is quite small and needs to be opened further away, to overlap at a larger distance, about 5 feet. Place your assistant at that distance and to your right so that he is about to dissappear completly from the interior mirror, and open the side mirror as far as possible without losing a slight sight of that's person. Move your head towards the passenger's seat and see when you see the edge of your own car in the mirror: It might be when you are in line with the center of the interior mirror, or with it's far edge.

This might feel uncomfortable at first, but it increases your field of vision dramatically. A small, eliptic auxiliary mirror mounted below the original mirror can be helpfull during parallel parking and reversing. Adjust it to show you a large portion of the car's body. It can also help if passengers obstruct your view in the interior mirror.

15. Blind-Spots
When you have adjusted your mirrors like this, you have very small blind spots that are almost none-existant and very rarely hazardous. However, there are actions to be taken to check those little blind spots too.

a) Blind spots in front of your front bumper or when you pull out from some stop signs or parking spots, that require looking over your shoulders and through the rear side windows, are not connected to mirrors, but it's important to mention them.

b) A scooter/bike over one lane aside: If I was hugging the left in the left lane and a bike was, for any reason, to hug the right side of his lane, the distance between the car exceedes one lane and at that distance there is usually a small blind-spot that the bike/scooter is normally just large enough to fit into. While it's extremlly rare for a rider to sit fully and over time in that blind spot, it's important to deal with it by:
(1) Constantly checking all mirrors, so that you are aware of all cars and bikes around you and know when they are inside your blind spots. (2) Make gradual lane-changes: First to the edge of your own lane, check side mirror again, move over. This also helps other road users to avoid you if you missed them/they missed you.

c) A scooter/bike in the third: It's important to know what is going on in the third lane. Usually, you can see cars in the third lane, but bikes can fall into a certain blind spot. Constantly checking the mirrors helps avoid this. This is the only case where the mirror requires being backed-up by a shoulder check. You simply tilt your head a bit to the side, start moving over and than add another little peek like this. The two peeks enable to look into the area hidden by the B pillars.

d) a curb when reversing: When reversing, we need to see part of the car's body in the mirror. For this, we need to tilt our head untill we see the car's edge. A small auxiliary mirror helps greatly. Remember, it's better to work hard during short, slow reversing/parking than in long drives.

e) a blindspot behind the rear bumper: Small objects can dissappear here. The auxiliary mirror I mentioned can help, but to cover it we need to monitor all mirrors constantly, reverse slowely and perhaps install reverse sensors that make a sound when you near an object.

f) An object hidden when the interior mirror is obstructed: Heads, headrestraints and rear doors can obstruct the view directly through the interior mirror. Again, you can tilt your head and/or install a small auxiliary mirror. The auxiliary mirror must be small and is best mounted below the original mirror, so that you can hide it if someone drives behind with rear beams.

g) A broken mirror: If someone breaked one of your side mirrors mid-travel, you can set a auxiliary mirror on the opposite side mirror, so that you can see directly behind, and than set your interior mirror slightly to the other side, where your side mirror was knocked off, and use shoulder checks when nessecary.

Trails for December

In this page, we summarize the tips and trails for the upcoming month: 

Reading the road surface:

Scan the road at the distance, checking both for hazards such as cars, bikes and pedestrians at the distance, but also look for changes in the shape and texture of the road surface at a slightly shorter distance (but still far ahead). Look for changes in tarmac color, for changes in the color of the water on the road (perhaps indicating a mixture of dirt or oil, or a deep puddle), for gravel and dirt, ice and snow, and for glimming surfaces (presence of oil or diesel).

Acquiring braking skills:

Learn to perform both emergency braking and performance braking. Go on an empty surface. Best when wet, to reduce tire wear. Set a point to start braking at. Use a few friends to help you: One or two to secure the surroundings, one to stand near the braking marker and blow a whistle to make your timing more accurate. 

Assest the braking distance at 50km/h. Now, head on and try to stop from that speed. Try a second time, after filling your tires with air appropriately. See the difference? Now, assest the stopping distance for 70km/h and than try it. See the difference? Before you run for the next time, consider your former attempts: Try to stomp on the pedal, not squeeze it down -- kick it. Practice with the standing car:

a) moving the foot off of the throttle as swiftly as possible

b) Keeping the foot in the air and than kicking the pedal at once.

c) If you have a clutch, move the left foot just after the right foot and not simultanously. Try do it simultanously when the car is standing and you will see you find yourself with both feet momentarily airborne and your leverage is hence crippled.

Try and perform this braking procedure at the test at 70km/h. Did it work? What was the difference? What did you feel? Was it juddering, or just screatching? If it was juddering, you have ABS. If it's screatching, you have standard brakes.

Next time, remove the cone, and have your friend sit with you in the car and guiding you around untill, suddenly, shouting at once and out-loud to brake (simulate a surprise) while clapping his hands against one another or against the dash. See how well you perform this braking procedure under surprise.

Having done this, try regressive braking. Set the cone, brake hard as before but than back off of the pedal and reapply a bit less hard, about 70% of pedal travel. See the difference in braking distance. Now, repeat, but this time -- when you ease-off and reapply, apply the brakes harder, untill you reach the point where you feel the car is slowing down as fast as possible, without the wheels locking up or the ABS working. You will feel the pedal become harder, somewhat vibrating even, and applying strong pressure against your foot. Repeat "pumping" the pedal like this untill you reach the desired result. Did you stop faster? Not yet, right?

Repeat the practice. Improvement is measured by the number of cycles you need to perform to hit that point and than keep it by constantly easing off of the pedal. This practice can be split for several days to avoid brake damage. Make stops between every attempt. 

Eventually, you should be able to hold the car at the threshold on just one cycle. If you do not have ABS, you can now work on classic regressive braking. I.E. Perform just that drill, but without letting go of the pedal, just brake hard to wheel lockup, wait a fraction of a second, and than back-off slightly (begin by simply curling your toes) to get the tires rolling again. If succesful, your braking distance should become somewhat shorter with one to three such backing-off operations.

Now, try to go for serious Threshold braking: Try to make the shortest stopping distance by applying the brakes hard -- but not all the way down and not in an instant application like before -- and nail just the point of the threshold, and than keep the car just on that point. Try performing regressive braking under surprise and than full-force emergency braking to finish with.

NOTE: This is only a preperation drill, it cannot replace practicing regressive/threshold braking with a personal trainer, and cannot teach you to apply regressive braking at a real emergency. Emergency braking is performed by braking as hard as possible as quickely as possible, and than pressing the clutch if existant.

Rain racing

Wet racing events are a unique experience, particularly for the unskilled and inexperienced. As such, it can be surprising, fun or, frightening. What's the difference? Obviously, water decrease grip levels. The tires must be treaded so that they could drain the water. This reduces the amount of rubber on the ground, and gives the tire an extra toll. At 60mph, the average road tire drains one gallon of water per second, all in the area of the contact patch alone! 

However, with the right tire, grip levels on a wet track or road are not drastically reduced. The serious problem begins when water mixes with other chemical agents. Soaked dirt turns into highly slippery mud, oil, diesel and rubber marks from tires -- all contributes to a further reduction in grip levels. Depth of water also changes the equasion. Banked pieces of tarmac can turn into little pools of water and foliage that are very slippery.

The way around this problem is based on driving style rather than mechanical car setup. The idea is to look for the grippiest parts of pavement. Those pieces are normally treated as where no one has driven before the rain, but it is in fact much more complex: Slopes tend to drain water away from certain positions on the track, while making other sides of it flooded. Also, the most common place for dust and even oil is the sides of the track, to where cars are skidding and on which "marbles" of dirt from the shoulders lay.

The rain line is normally sharper and tighter. First, we brake slightly earlier and deeper into the turn, and wait for a relativelly late stage to turn the wheel. Not the average late APEX, but a still-later one. At the right moment, we turn the wheel decisivelly into the turn and than let the car turn by it's own, while trailing off of the brakes. Also, as we turn-in, APEX and Track-out, we would not be using the whole width of the track, because the built-in banking of the track surface will cause water drainage to the sides of the track.

Things to beware of:

1. Glimmering surfaces: As you look up, scan the road surface ahead for anything shiny. This would indicate oil or diesel, which decreases grip levels. Beware of them and adjust your line to avoid them where possible and/or beneficial. If you must drive over a relativelly slippery part of road, try to adjust your line so that you drive over it with a minimum of steering input, at a reasonable speed and as close as possible to a constant speed.

2. New pavement or concrete are normaly more slippery, though not quite as the former. They often requires changes in line and pace.

3. Standing water and streams should be avoided where possible. They can result in hydroplaning, which creates the most dramatic reduction of grip, only comparable to glare ice or skidpad enthol. 

4. First rain: The more dry and hot the road surface is, the more slippery it turns when soaked in water. Even on a dry track, dew can absorb oil and dust and create little points that are almost as slick as first rain. Whenever it rains after 4 days of dry weather, it is a first rain. First rains are also a psychological hazards because drivers take time to readjust themselves to the conditions.

The second problem: Visibility

Visibility in the rain is reduced. Check the glass of the windscreen, side windows, rear window and helmet, and even use special materials that can be scraped over the glasses from the inside (and some from the outside) to avoid the fogging of the visor. Most airconditioned cars have the ability to defume the front windscreen, and sometimes the side windows and the mirrors. Use these options. Combine them with cold air intake from external circulation and a partially open window.  For fog on your helmet-visor, breath downwards.

The greatest hazard: Hydroplaning

Hydroplaning is when a car exceeds it's ability to drain the water on the surface. The result is for the car to skim somewhat over the water, reducing grip levels to about 0.1 as slippery as glare ice, on normal tires! The feeling is that the car's progress and acceleration are somewhat hindered and engine RPM increases. The wheel feels very light.

During hydroplaning, any sudden movement will jerk the car into a nearly irrecoverable skid. The normal course of action is thus to gently-gently reduce throttle input to a minimum, without lifting-off. If ineffecient, ease off of the pedal completly. If this is inefficient, reapply slightly. If this is inefficient, or if the car skids, declutch. In the latter case a steering correction will also be required.

If you get oversteer and you try to use the throttle to renew rear grip, you are bound to either overpower the rear wheels of a rear-wheel drive car (making the situation worst) or spin the front wheels of a FWD to a level where no forward acceleration or weight transfer takes place. The line between too little and too much is more thin as grip levels are reduced, so we simply bang down on the clutch. This gives us natural tire rolling action that helps reduce the slip angles (no tractive forces working on the tire), a bit of acceleration during oversteer or a bit of deceleration during power understeer or even power oversteer.

A note on setup

Besides changing tire type, other changes can also make a car more fit for rain racing. A car on the rain tends to slip less and roll less. Hence, making the car generally softer, and maybe readjusting it's camber are helpful.

Coefficients of Friction

I have compiled the grip levels on various road surfaces:

• Dry Pavement: 0.89-0.75. Ranges between high quality tarmac and racetracks and main roads, to bumpy, cracked tarmac, concrete, or white/scrubbed tarmac.
• Wet Pavement: 0.60-0.50. Depending on water depth and the type and smoothness of the soaked road surface.
• Dirt, Grass; Gravel, Mold, Rocks: 0.58-0.42. Gravel, mold and rocks are less grippy, but a wheel sliding over gravel or loose dirt, tends to dig into them, hence slowing down and regaining grip. With gravel, it also finds a grippier layer beneath.
• "First Rain:" 0.38-0.32. A small rain shower after at least three days of dry weather and some traffic. This causes dirt, oils, rubber left-overs and acrilic colors, to float over the water, making it seriously slick. Even when the water dries out, the foliage can remain.
• Diesel, Petrol, oil, brake fluid, fresh tar: 0.30-0.20. These are all defined as oils, but these are rather sticky, giving better grip that most people think. They tend to become quite more slick when they absorb moist.
• Mud: 0.30-0.25. Mud and animal feaces are to be aware of when driving on rural roads.
• Partial frost/Hail: 0.60
• Advanced frost: 0.53
• Full frost: 0.39
• Fresh Snow: 0.36. Grippy tarmac beneath can help make slides more recoverable, like with loose dirt.
• Packed snow: 0.35. Chance of frost or ice beneath the snow.
• Snow and ice: 0.32
• "Black ice": 0.30. Small, thin layers of frost that are penetrated by sun rays.
• Bright/wet ice: 0.24
• Motor/gearbox/differential oils: 0.19
• Glare ice: 0.19. Ice at the temperature range that offers minimal water buildup untop of the ice.
• Skidpad surface: 0.12. A surface made of a chemical agent (enthol) resembling icy condtions or hydroplaning.
• Hydroplaning: 0.15-0.9.