Friday 26 July 2013

Understanding Understeer from Oversteer

Graphic Illustration of Understeer vs. Oversteer
Source: Google Images


As a car enthusiast, I literally eat, sleep and dream cars, but I always tend to struggle with understanding the terms: Understeer and Oversteer. Whenever one watches a car related programme you always tend to hear the motoring terms: Understeer and Oversteer. With this blog, I will attempt to explain: Understeer and Oversteer. I hope that you enjoy the read!

Top Gears: Richard Hammond explains Understeer and Oversteer

What is Understeer and Oversteer? These are predominantly vehicle dynamics terms used to describe the sensitivity of a vehicle to steering. Simply put, oversteer is what occurs when a car steers more than commanded by the driver. Whereas, understeer occurs when a car steers less than the amount commanded by the driver. Some motoring journalists attribute “Understeer” to Front Wheel Drive (FWD) cars, whereas Rear Wheel Drive (RWD) cars predominantly “Oversteer”, which makes them the ideal car to use for drifting.

Now that you are aware of what “Understeer” and “Oversteer” is, I will now go about explaining Oversteer and Understeers, as well as the causes and methods to correct both Oversteer and Understeer if are faced with the situation.

Explaining Oversteer
As a driver it’s unlikely that you’ll ever experience oversteer unless you’re driving/pushing a car over its limits of grip. According to DrivingFast.net, You can recognise oversteer if:

·         The rear of the vehicle becomes unstable and ‘light’ due to lack of grip.
·         The car starts to rotate so the driver is facing towards the inside of the corner.

There are four major causes of oversteer:
1.    Entering the corner too fast.
2.    Accelerating into the corner, too early or too aggressively.
3.    Braking into the corner or mid corner.
4.    Lifting off the throttle mid-corner.

Correcting Oversteer.
DrivingFast.net explains how to correct oversteer: “Whatever the cause of oversteer it is important to keep the front wheels pointing in the direction you're hoping to go. If you fail to do this, the most likely result is a spin. You should apply enough steering lock to point the wheels in the direction of the slide. Too little and you're likely to spin as the back continues to come round, too much and the car will rapidly over-correct, often resulting in a spin in the opposite direction. The skill can only be mastered with plenty of practice and should become instinct if you're planning to drive fast on a track.”

Explaining Understeer
As stated previously Understeer will not happen if you aren’t pushing a car to its limit. Understeer is most likely to result from these situations:
·         Accelerating into a bend
·         Braking into a corner
·         Ploughing into a corner too fast
·         Low traction conditions on the corner such as ice or oil

Active causes of Understeer
·         Cornering speed
·         Throttle
·         Braking
·         Steering inputs
·         Weight transfer
Recommended ways to correct understeer are:
  • Be as smooth as you can
  • Don't enter corners flat out, and accelerate as you exit
  • Don't brake in a corner. The only exception to this is if you are using trail braking...


One can now establish that “Understeer” and “Oversteer” are will most likely to occur when pushing your car to the limit. In conlusion, I believe that you should only experience these driving dynamics on a racetrack, because tracks are there for racing and many tracks are open to the public. Therefore, I suggest rather push your car on a track/circuit than on the street because you’d be much safer. I hope that you have enjoyed this new blog!