Author: Monica Clara Brand
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In this second lesson we'll learn about understeer and oversteer and how to correct it.

First let's see why any of them occur so let's talk about weight transfer.

Weight transfer occurs everytime you change something in your inputs to the car.If the car brakes,the weight moves to the front,if the car accelerates,the weight moves to the back,if the car steers left,the weight moves to the right and viceversa(actually front-right,then when it settles in the corner it moves more to the right).

This is all due to inertia.
Managing weight transfer in a race car is one of the most important things because it can teach you how you can prevent or command either understeer or oversteer.

1.Understeer

Understeer occurs when the weight is more to the back of the car and you accelerate while having too much steering input and too little front traction.

You noticed on the skidpad that when you accelerate past the neutral limit of the car,the circle the car takes is becoming wider and wider.If you turn the steering wheel tighter while still accelerating,the circle gets wider still until you run out of road.This happends because accelerating you transfer weight to the back,making the front of the car lighter and unload the front tires.

What you need to do is transfer some of that weight back to the front tires,loading them and giving them back the grip needed for the car to turn.

You can accomplish that by lifting a little off the gas pedal to move the weight forward and help the front tires regain grip.

Let's go to the skidpad again.

You will notice that when lifting off the car will turn how it should rather than continuing to run wide.How much the car will regain traction and turn depends again on the weight transfer to the front tires.How much weight transfer occurs depends on how much you lift and how sudden you lift.If you lift too little and too slow,the car will recover from understeer slower.If you lift too much and too fast,you might get too much wight transfer to the front,thus unloading the rear tires and getting the car to oversteer.

You need to practice doing this with just as much correction as is necessary to get the car back to a neutral behavior.

2.Oversteer

Oversteer occurs when you have too much weight transfer to the front and too little traction to the rear tires.
You can induce oversteer in two ways.

The first way is the trailing throttle oversteer.I mentioned earlier about this situation.Go to the skidpad,get your car up to speed and then lift off of the gas pedal fast and completely.You will see that the weight is trasfered to the front,giving the front tires a lot of grip and unloading the rear tires taking the grip away from them.As this occurs,the car will rotate and give you oversteer.

The second way is power oversteer.This occurs when there is not enough load on the rear tires and you accelerate too hard.Go to the skidpad,get the car in a neutral behavior and then accelerate hard and fast.The power will overcome the tires ability to grip and you'll oversteer.The severity of the oversteer again depends on how fast and hard you accelerate.

When the back end starts to come arround,you need to turn the steering wheel into the direction the back end slides,so basically into the slide,catching the slide and then turn back the wheel to it's center as the slide angle decreases.

Most people don't get the steering wheel back to it's center position as the slide angle decreases,thus making the car slide in the opposite direction.

It's very important to center the wheels again otherwise you won't save the car.

You can add a little throttle,but just the right amount as too much throttle,as I've explain earlier,will actually increase the slide.

Practicing understeer and oversteer and recovering from them on the skidpad at different speeds will give you more understanding on what the weight transfer does and how you can use it to your advantage.

Now go play with the throttle!
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