A non-skidding tyre is not moving LATERALLY relative to the road. So static friction is the main factor. Once you start to skid then it's not.. which is why you can no longer steer when your are locking the wheels up under braking.
As soon as you are turning there is slip even if you are turning a tinsy winsy bit. Its producing camber thrust and that is what makes you turn. When the tyre is skidding you have exceeded its maximum slip angle and it is no longer producing camber thrust so it can't turn.
I didn't even need to google that 😉
Good god is there nothing we won't argue the shit out of on this forum? Really?
Good god is there nothing we won't argue the shit out of on this forum? Really?
I was just thinking that was what made this place so good 🙂
Was just thinking this morning how some other forums I am on are so boring in comparison. I mean who wants to talk bikes all the time 🙂
I think the *ahem* disagreement above is a good reason for me to get some more driver training and experience. Whatever the physics, the corrective response to an "incident" needs to be the correct one and it needs to be instinctive. If I skid on snow in a front wheel drive car I instinctively know what to do and have got myself out of mischief on more than on occasion. My instinctive - and incorrect - reaction to over-steer in a RWD car got me into trouble.
As soon as you are turning there is slip even if you are turning a tinsy winsy bit
No, I think it's more complicated than that. There's flex in the rubber of the tyre which means that as the wheel rotates and brings new un-flexed tread into contact with the ground the tyre will 'walk' slightly towards the outside of the bend. This is not the same as breaching the limits of static friction. It's why pushing it on road tyres feels different to actually losing it, and one reason (a big one I expect) why slicks work better than normal tyres.
I was just thinking that was what made this place so good
The recent thread on art appreciation WAS a good example of what this forum can do. But this?....
(I'll add a 😉 at this point to be sure no-one takes offense).
No, I think it's more complicated than that. There's flex in the rubber of the tyre which means that as the wheel rotates and brings new un-flexed tread into contact with the ground the tyre will 'walk' slightly towards the outside of the bend. This is not the same as breaching the limits of static friction. It's why pushing it on road tyres feels different to actually losing it, and one reason (a big one I expect) why slicks work better than normal tyres
There is actually some truth in what you are saying there, but it does not actually change the physics of what you should do in the event of under-steer.
But I am going to bow out as this is not the Bazzer and Molgrips show 🙂
Back in the day as young lads in overpowered (for the day) poor handling RWD cars (3.0 & 2.8i Capri's, V8 SD1s, etc.) we learnt through experience chucking 'em round deserted car parks late at night, preferably in the wet or snow. Often the Police would pop by to check us out, and were always very reasonable about it (don't make too much noise etc.).
I don't envy the task of young enthusiastic drivers these days. Modern cars handle so incredibly well (especially the sporty versions) that by the time an inexperience driver has reached the limits of handling it's often all over.
+1 Tucker.
Bazzer - damn right there's truth in what I say 🙂 I'm not seeking to change the laws of physics, just apply them properly. There are lots of factors that determine behaviour, that's all I am saying. General rules might not apply in certain situations and in certain cars. Loads of variables.
Molgrips has failed to convince me; I've never seen a car being driven competitively that has gone round a corner like most of the Top Gear's 'Star in a reasonably priced car' contestants at the Hammerhead...that is full lock and going wide 🙂
I think the winding more lock on method is just a 'cross-your-fingers' approach to getting round a corner 🙂
+ 2 Tucker.
This was going to be my approach, but I couldn't think of anywhere to do it [s]without some busy-body trying to stop me[/s].
Bazzer - damn right there's truth in what I say I'm not seeking to change the laws of physics, just apply them properly
Well I was going to bow out. The only truth in what you were saying is about tyres deforming so thus the contact patch changes with load so hence so its not as simple as( force = contactPatch x coef of friction) as the contact patch can change due to load.
But just throwing random facts about does not prove your case.
Why not explain why all this means I am wrong rather than just trying to blind me with science.
I think the winding more lock on method is just a 'cross-your-fingers' approach to getting round a corner
Exactly
I do have practical experience of this as well, doing it wrong before I new better meant I hit the tyre wall at Castle Coombe on Quarry bend at about 60MPH.
Learning what works had kept me off the tyre wall since.
Molgrips has failed to convince me; I've never seen a car being driven competitively that has gone round a corner like most of the Top Gear's 'Star in a reasonably priced car' contestants at the Hammerhead...that is full lock and going wide
In that situation I'd completely agree. Smooth tarmac, fast long corners, different car, absolutely. I've really not got much experience at those kinds of speeds.
However, what I've been trying to say this whole time is that different situations (mud, snow, gravel, Austin Metro, whatever) MAY behave differently.
Why not explain why all this means I am wrong
I'm not trying to say you are wrong! I'm trying to say that there are many variables which might mean different techniques might work. I'm not talking about racing here.
Another big thumbs up for Andy Walsh at CarLimits, airfield day was essential when I first had my Elise, learnt a lot.
I did a skid pan session at Castle Combe and learned loads about handling and recovery of skids and the physics of over/under steer.
I've just done (today) my second trackday so I'd class myself as a novice. The trackday definitely wasn't the place to be exploring the limits of the car or driver. Not the place to learn about car handling but learned plenty about the racing line!
I can also confirm that lifting off in a RWD car in most of the corners at Donington (especially Redgate and Craner Curves) invariably results in a spin.
Sounds like an airfield day is what I need. Anyone know any nearer than Essex? I'm in Staffordshire
Another big thumbs up for Andy Walsh at CarLimits, airfield day was essential when I first had my Elise, learnt a lot
Did you do the thing where you come flying onto the main runway from the side and try and turn in and get loads of under-steer, then come in and turn in on the brakes and see the understeer go away ?
With sticky A032R's on the 7 I had to go further up the escape road to get enough speed to get understeer, to the point it was quite scary knowing you were going to slide at 95MPH plus 🙂
I don't think track days or airfield days are the answer. Track days because the tracks are so very smooth and grippy, nothing like a public road surface. And airfield days because the taxiways are so very rough and grippy (not to mention tyre shredding), again, unlike the road.
Skid pan as already suggested.
Track days because the tracks are so very smooth and grippy, nothing like a public road surface
Have you ever been on a track with slick tyres when the rain comes? Smooth maybe. Grippy? Nope. I spent a lot of time on the grass at 3 Sisters being caught out in a kart in the rain whilst on slicks. That's what made me realise I needed some driver training 😆
a trackday will teach you nothing youare wanting to learn, as has been mentioned several times skid pan/ car control day is what you require.
as for the understeer ime (which is alot when it comes to high power fwd cars) once you have understeer induced the only way to get rid of it is to remove some of the power and some speed take off alittle lock to allow the wheels to grip again, ive never driven a car that when understeering applying more lock causing the rear end to come around, and i cannot see how that would happen, removing all the power will cause alot of fwd cars to lift off oversteer, so its all about being smooth.
bazzer what did you hit the wall in ??
this is me last year at combe
Did you do the thing where you come flying onto the main runway from the side and try and turn in and get loads of under-steer, then come in and turn in on the brakes and see the understeer go away ?
Done that, is great fun. I don't have stickies on my Elise though so don't need the extra run up. Have seen Andy do it loads of times where he starts on the perimeter road to get enough speed! Best bit about that bit of the day for me was finding out that you can come off the throttle in a RWD car mid corner and not spin.
ive never driven a car that when understeering applying more lock causing the rear end to come around
Austin Metro, Leominster bus station car park with three inches of slush and snow, circa 1993 🙂
