Severe understeer help!
Discussion
Heres the problem, I have a 106, lovely car to drive, lift-off oversteer on demand and very driveable most of the time.
Last week while having a fairly sporting drive I overcooked it into a roundabout in the rain and as I turned the wheel it sailed straight on in a straight line
after (very) quickly analysing the situation I realised I couldn't;
a) Brake, would have probably just locked up and continued going in a straight line.
b) Accelerate, see above
c) Do nothing, see above again.
so the only option I decided was;
d) tug the handbrake slide the back and drift it round the corner, luckily for me this worked a treat and the car hung the back end out and went where i wanted it to, applying the power as I went to stop it completely swapping ends.
I know that I should have paid more attention to the conditions as I entered said roundabout, and slowed down accordingly, so have learnt a valuable lesson about arsing about in such conditions.
Normally in such a position the front end hangs on for grim death and I lose the back first which is easy and fun to recover.
Any advice on how t deal with understeer like this again please?
Was pulling the handbrake the correct thing to do? Seemed like the only option at the time...
I also should point out that the road was completely deserted about 1am so I wasn't putting any other motorists at risk.
Any advice appreciated, thanks!
Last week while having a fairly sporting drive I overcooked it into a roundabout in the rain and as I turned the wheel it sailed straight on in a straight line
after (very) quickly analysing the situation I realised I couldn't; a) Brake, would have probably just locked up and continued going in a straight line.
b) Accelerate, see above
c) Do nothing, see above again.
so the only option I decided was;
d) tug the handbrake slide the back and drift it round the corner, luckily for me this worked a treat and the car hung the back end out and went where i wanted it to, applying the power as I went to stop it completely swapping ends.
I know that I should have paid more attention to the conditions as I entered said roundabout, and slowed down accordingly, so have learnt a valuable lesson about arsing about in such conditions.
Normally in such a position the front end hangs on for grim death and I lose the back first which is easy and fun to recover.
Any advice on how t deal with understeer like this again please?
Was pulling the handbrake the correct thing to do? Seemed like the only option at the time...
I also should point out that the road was completely deserted about 1am so I wasn't putting any other motorists at risk.
Any advice appreciated, thanks!
Getting this kind of understeer would suggest two things:
1) carrying too much speed into the corner
2) applying steering input too quickly/not smoothly
Tugging on the handbrake seems to be a route likely to end in disaster though. Definately not the ideal route to recovery, lucky escape maybe?
1) carrying too much speed into the corner
2) applying steering input too quickly/not smoothly
Tugging on the handbrake seems to be a route likely to end in disaster though. Definately not the ideal route to recovery, lucky escape maybe?
7db said:
1. straighten, lift off to get weight on nose, stop aquaplaning, regain grip, reapply steering smoothly this time. hope there's room for all this.
Agree with this, although you were probably already lifting off and skidding rather than aquaplaning. It takes some courage to unwind lock when skidding towards something but still probably the best thing to do. Having applied the handbrake and got the car sideways, could you have hit a kerb and rolled the car? I appreciate you didn't so in the circumstances, well done!
I think the best way out of that situation would be to off enough lock off for the front wheels to regain traction, brake down to an appropriate speed for the corner (and hope you still have enough space left to do this) and then ease off the brakes and turn in. You don't need to completely straighten the steering while you're braking, so you may find you can just take a very wide line through the corner rather than literally going straight on under braking.
The other thing to do would be to remove some steering - you'd probably gone over the hump in the steering vs grip curve, so taking some steering off would have actually given some more lateral force and more turning. It's probably why the handbrake was such an effective tool - it rotated the car and reduced the front wheel slip angle at the same time.
Cheers guy much appreciated.
Luckily I have experience rallying and have been taught how to deal with handbrake turns through training, just never understeer which is odd!
The releasing lock option sounds good, not too sure I like the idea of anchoring up and hoping to lose speed though!
Luckily I have experience rallying and have been taught how to deal with handbrake turns through training, just never understeer which is odd!
The releasing lock option sounds good, not too sure I like the idea of anchoring up and hoping to lose speed though!
Nic Jones said:
The releasing lock option sounds good, not too sure I like the idea of anchoring up and hoping to lose speed though!
Hitting the brakes isn't *always* the right answer, but it is the right answer enough of the time to be a good thing to do by default if you can't figure out what else you should be doing.
Thinking about it.
In the case of severe understeer - what would happen if you just stamped on the brakes - given the car is fitted with ABS?
I would presume that the system would turn as much as the ABS system was capable of doing...
I'd love to try that on a skid pan.
I've done the brake-steer-release thing (on a car without ABS)(which works) but only when understeering under braking. Going in hot enough to understeer through sheer speed would the same thing work? Presumably it would just not as well...
>> Edited by Don on Tuesday 23 May 18:58
In the case of severe understeer - what would happen if you just stamped on the brakes - given the car is fitted with ABS?
I would presume that the system would turn as much as the ABS system was capable of doing...
I'd love to try that on a skid pan.
I've done the brake-steer-release thing (on a car without ABS)(which works) but only when understeering under braking. Going in hot enough to understeer through sheer speed would the same thing work? Presumably it would just not as well...
>> Edited by Don on Tuesday 23 May 18:58
On track when I've fecked it up and gone in to a corner too hot I've always just lost some lock until the wheels grip again. With my worst mistake (absolutely no hope of getting round) I just kept my foot hard on the brake and didn't turn in. There enough space usually (on track) to keep slowing until you can limp around the outside of the track looking shamefaced...
Not so much spare room on the road!
Not so much spare room on the road!
Don said:
Thinking about it.
In the case of severe understeer - what would happen if you just stamped on the brakes - given the car is fitted with ABS?
I would presume that the system would turn as much as the ABS system was capable of doing...
I'd love to try that on a skid pan.
I've done the brake-steer-release thing (on a car without ABS)(which works) but only when understeering under braking. Going in hot enough to understeer through sheer speed would the same thing work? Presumably it would just not as well...
No such luxurys as ABS, hell it doesn't even have power steering!
On the outside was big armco type barrier hence I didnt really want to slide off the road!
Handbrake seemed sensible as I have enough experience of the car during a handbrake turn (autotesting etc.) to know/guess what it how it would respond and then steer/accelerate accordingly.
Don said:
Thinking about it.
In the case of severe understeer - what would happen if you just stamped on the brakes - given the car is fitted with ABS?
I would presume that the system would turn as much as the ABS system was capable of doing...
I'd love to try that on a skid pan.
If you are already understeering the (ABS) brakes aren't going to have any great effect until the wheels start to regain some grip. It's only as the effect of understeer diminishes that the effect of brakes will increase. The path the car takes without braking & with braking will be pretty similar (until late on when speed has been scrubbed off), the higher the initial speed the longer you'll have to wait. In a car without ABS, on that path of understeer, as soon as you brake the car will come off the curved path with a slight jerk towards straight ahead & plow on where the nose points until you come off the brake.
There is no substitute for getting rid of as much speed as possible BEFORE the onset of the understeer. The more you get, the more room you'll need as it becomes less manageable.
>> Edited by vonhosen on Tuesday 23 May 21:15
Nic Jones said:I was really surprised to read this, since from my understanding, one of the first things you must master when learning to drive competitively on loose surfaces (I assume "rallying" means loose-surface rallying) is how to fight understeer. The hand-brake turn is one of the manifestations of attempting to overcome loss of steering force, and therefore slow turning rate, caused by lack of grip on the front tyres.
Luckily I have experience rallying and have been taught how to deal with handbrake turns through training, just never understeer which is odd!
For overcoming understeer during normal road driving, it's generally best to ease off the throttle and straighten the steering wheel. If that fails (or you think it will), then get on the brakes hard while unwinding the steering wheel; once enough speed has been scrubbed off, then get off the brake and progresively steer to your desired direction.
Hand-brake turns and other methods of turning the car works within parameters, but once those have already been exceeded, they won't help you. You were lucky that your speed was not excesssive for a hand-brake turn, and there was enough room for you to attempt the manouevre.
>> Edited by Jungles on Wednesday 24th May 05:11
>> Edited by Jungles on Wednesday 24th May 05:12
vonhosen said:
There is no substitute for getting rid of as much speed as possible BEFORE the onset of the understeer. The more you get, the more room you'll need as it becomes less manageable.
Well of course!
...and thanks for your thoughts on how ABS might affect understeer. I'm seriously tempted to book onto Goodwood's skid pan as they have an ABS car (as well as the sheds!) to play with. Some very interesting experiments...
Jungles said:
Luckily I have experience rallying and have been taught how to deal with handbrake turns through training, just never understeer which is odd!
For overcoming understeer during normal road driving, it's generally best to ease off the throttle and straighten the steering wheel. If that fails (or you think it will), then get on the brakes hard while unwinding the steering wheel; once enough speed has been scrubbed off, then get off the brake and progresively steer to your desired direction.
Hand-brake turns and other methods of turning the car works within parameters, but once those have already been exceeded, they won't help you. You were lucky that your speed was not excesssive for a hand-brake turn, and there was enough room for you to attempt the manouevre.
>> Edited by Jungles on Wednesday 24th May 05:11
>> Edited by Jungles on Wednesday 24th May 05:12
Sorry what I wrote was wrong,
I learnt about handling handbrake turns through practice on autotests where you never go quick enough to understeer, but have to use the handbrake to slide the back through a box of cones so a 'controlled handbrake turn' (contradiction?) is needed.
I should have pointed out that I co-drive on rallies and have picked up a lot of tips and tricks, ie left foot braking.
Unfortunately in a severe understeer moment I try not to look up from the nav seat, as it tends to end with a bump I've noticed in the past!
Nic
Don said:
Going in hot enough to understeer through sheer speed would the same thing work?
You can do that on our skid pan and the clutch in, straighten steering a bit, regain grip, steer again slowly does work.
Even at skid pan speeds you nearly run out of room, though because of the v low friction and silly tyres regaining the grip happens more slowly and more gently than with normal tyres and grip.
The last time I was on the pan one of the instructors had bent one of the training cars on this exercise the day before, so not the thing to be practising on Her Maj's highway I reckon.
BliarOut said:
Skid pan.... Did you say skid pan FiF? After a recent "incident" I want to get myself on one and brush up on my ability to catch tail slides.
Is it available to the public? What sort of costs are involved?
Lots of the tracks have skid-pans. My IAM Group takes groups of 12 to our local pan (Goodwood) to go play and see how cars react in varying scenarios.
One thing I try to remind everyone though is that there is still a world of difference between tackling slides at 12 miles an hour on a surface equivalent to glass covered with grease and dealing with one at 100mph on grippy tarmac absolutely shitting yourself because the hedge is coming up very rapidly...or even dealing with one at 40mph on a roundabout on wet day. Very different when it really matters...
I still recommend the pan as a learning experience, though!
Our Group visits cost £45 each. A dedicated three hour session with the pan to yourself would be more like £200.
>> Edited by Don on Thursday 25th May 07:40
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