Car Throttle explains Oversteer vs UndersteerMay 21, 2017
Every BMW fan should be aware of what oversteer is. The art of sliding the back end of a car around is something that BMW enthusiasts take pride in learning. With punchy engines up front and drive going to the rear, BMWs have always been great cars to oversteer. Typically, BMWs aren’t very understeer-y cars by nature but it’s not something outside the realm of possibility. A good driver knows the difference between both and knows how to correct them. In this video from Car Throttle, you can learn the differences between the two and how to correct them.
One of the first things you learn before going racing is that tires can only do three things, accelerate, brake and turn, and only have enough grip to do one at a time at speed. With understeer typically occurs with front-wheel drive cars, as the front wheels are tasked with doing the accelerating and turning. If you add too throttle while turning, there’s simply not enough traction from the front tires to grip the road. Also, the back end isn’t being rotated around the corner like in a rear-wheel drive car. According to The Grand Tour’s Richard Hammond, the result is that the car continues to go more straight than turn and you end up crashing into a tree and dying…
Understeer can usually be corrected pretty easily, which makes it the safer of the two. For understeer, just back off the throttle, reduce turning lock and wait for the tires to regain their grip and try again. It’s usually pretty easy to correct and typically doesn’t end up in crashing if you know what you’re doing. What you should never do is completely lift off the throttle, as that sends the weight of the car forward to the front wheels, increasing grip of the front tires but reducing grip on the rear tires and you get lift-off oversteer, crash into a tree and die. So just ease of the throttle, but not all the way, and try to correct the steering.
Oversteer is when there’s not enough grip for the rear tires, overwhelming them, and the back end of the car over rotates. If you know how to control oversteer, it can be a lot of fun in a safe environment. There’s an art to having a car dance right on the limit, and past the limit, of adhesion. Oversteer is what you see in BMW commercials and action movies because it looks awesome and is a ton of fun, if done properly. If you don’t do it properly, you will do a big spin, crash into a tree and die.
To manage oversteer as the rear end is over-rotating, you must counter steer by adding opposite steering lock and slightly back off the throttle. Once again, do not completely lift off the throttle, as then the rear tires will regain grip and launch the car in the opposite direction, thanks to opposite lock being applied. So just gently back off the throttle, add counter steer and manage both until the car straightens out.
Oversteer is more frightening to people who’ve never felt it before but it’s more fun to enthusiasts who are accustomed to it. Whereas understeer is more frustrating for enthusiasts than anything else but safer for the novice. Now that you’ve learned the art of managing both oversteer and understeer, you can prevent yourself from crashing into a tree.