Understeer, oversteer

[S3Bangs]

Curse me if you like.. /ubbthreads/images/graemlins/tongue_out.gif Im absolutely inept when it comes to cars.. I know a few bits but hey.. I have my limits. You have as much chance of finding me under a car as much as finding an ashtray on a motorbike.. /ubbthreads/images/graemlins/tongue.gif

I keep hearing oversteer this, understeer that on this site when people talk about driving on this forum... As far as I know... I know the limits of my car round the bends and on straights, so even though I drive like I stole it (Al. /ubbthreads/images/graemlins/grin.gif), I know when it doesn't feel right.

What I really dont know is which ones oversteer, which ones understeer.. how can I tell the difference, what does it feel like.. saying that, the way I drive, I might've felt it and not known thats what it was

There you go... /ubbthreads/images/graemlins/wink.gif Treat me gently... /ubbthreads/images/graemlins/lol.gif

 

[RichA3Turbo]

Understeer is when you have to turn the wheel further than you would normally to make the same bend, cos the front wheels want to go straight straight not left/right, and oversteer (usually from rear wheel driv cars) is the complete opposite, you turn the wheels less than normal to make the same bend.

make sence? /ubbthreads/images/graemlins/crazy.gif

Rich B

 

[Mark]

Oversteer is when you overwhelm the rear tyres and the back end loses grip. Usually happens when you lift off the throttle mid-corner in an AWD car.
Understeer is when the front tyres lose traction, the car doesn't turn as sharply as you would expect for the amount of steering input.

To correct oversteer, a combination of steering and throttle is needed (best pracised on track). To correct understeer, lifting off the throttle usually does the trick. Most road cars are set up so that entering a corner too fast provokes understeer since your average panic reaction is to lift off the throttle, which corrects understeer but can make oversteer turn into a spin.

I could tell you all about tyre slip angles but it's probably more than anyone needs to know for road driving....

 

[Gambba]

[ QUOTE ]
Mark said:
Oversteer is when you overwhelm the rear tyres and the back end loses grip. Usually happens when you lift off the throttle mid-corner in an AWD car.
Understeer is when the front tyres lose traction, the car doesn't turn as sharply as you would expect for the amount of steering input.

To correct oversteer, a combination of steering and throttle is needed (best pracised on track). To correct understeer, lifting off the throttle usually does the trick. Most road cars are set up so that entering a corner too fast provokes understeer since your average panic reaction is to lift off the throttle, which corrects understeer but can make oversteer turn into a spin.

I could tell you all about tyre slip angles but it's probably more than anyone needs to know for road driving....

[/ QUOTE ]

Oversteer IMO and I would say most others as well is far far better than understeer, as understeer makes you very slow in corners. So Al on the above explanation and what I've just said you should know that our Audi's have crappy understeer (But safe), so for that reason I prefer driving my BMW.

 

[Mark]

The best setup, and the one I strive for when I go testing in my racecar is a neutral one.
There is nothing like a car which doesn't have a tendency either way - it can be so controllable, you can almost drive it on the throttle alone, just using the steering wheel to point it into a corner.

Another description of oversteer and understeer I heard recently - Oversteer is when you see the hedge you're about to hit in the mirrors, understeer is when you see the hedge you're about to hit through the windscreen.

 

[S3Bangs]

Hmmm... Ive always wondered why my car tried to shoot towards the railings going quickly round the bends... /ubbthreads/images/graemlins/blush.gif
So what you're all saying is never to lift throttle halfway through a bend...even though you feel putting your foot on it will make u lose the back

 

[Gambba]

[ QUOTE ]
S3Bangs said:
Hmmm... Ive always wondered why my car tried to shoot towards the railings going quickly round the bends... /ubbthreads/images/graemlins/blush.gif
So what you're all saying is never to lift throttle halfway through a bend...even though you feel putting your foot on it will make u lose the back

[/ QUOTE ]

No.....when driving the Audi it's essential that as you feel the car going straight instead of around the bend that you lift off the throttle, and in extreme cases a dab of the brakes (BUT NOT advisable), as you gain control of understeer you need to watch out for oversteer as the tyres regain grip. Only in oversteer do you not ease off mid-corner, a bit of throttle a power it out, but all cars act slightly different.

 

[mramage]

This is a very good site on technical issues :

http://autozine.kyul.net/technical_school/tech_index.htm

In particular, the follow section talked about handling :

http://autozine.kyul.net/technical_school/handling/tech_handling_4.htm#Neutral

Apologies if someone has already posted this before.