ScoobyChris

A safe speed is defined as one at which the driver can safely stop on his/her side of the road (in the distance he can see to be clear), and this will take into account any immediate hazards, prevailing weather conditions, condition of surface of road, condition of tyres, etc, etc.

The limit point is defined as the furthest point that you can see to determine this safe speed, and could be a crest in the road limiting vision, or the furthest point you can see round a bend, and you will be able to comfortable stop before the limit point.

So how do we use the limit point to determine a safe speed for cornering?

The basic theory is that, as a driver approaches a corner, the limit point will remain static and this is the point where the driver should be doing his braking. As the driver gets closer to the corner, the view into the corner improves and the limit point will start to move at the same speed as the car. So at this point, the driver can come off the brakes and apply power to begin driving through the corner. As the driver reaches the apex of the corner, the limit point will start to "run away" from the car and this is the point at which the driver can "chase" the limit point and begin to accelerate firmly.

To enable the limit point to start to move earlier in the corner (ie the point at which the driver can get on the power), the car can be positioned towards the offside, ie crown of the road, for left hand bends and towards the nearside for right hand bends....

Chris

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Holding up the traffic in a little Italian..........

KenONeill

Yes, fine as far as it goes, but I've also seen the opposite argument appplied wrt positioning. That is, you should position yourself as far left as possible on left-handers, in order to leave more space for the idiot who's coming the other way and taking what they fondly imagine to be a fast racing line through a blind bend!

ScoobyChris

As I said, it's the basic, read general, theory. In practise there are lots of other things to consider and you should only move out to the crown of the road to enhance an already good view, rather than to create one, which could leave you in the situation you describe....

Of course, if you're travelling at a speed appropriate to the limit point, then you'll be able to safely stop in plenty of time should someone cut the corner in front of you.....

Chris

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Holding up the traffic in a little Italian..........

ncarring

If you're further out, you can see the idiot coming sooner!

Position to the left on Right handers for Safety, Stability and View.

Position to the right on Left handers for Stability, View and Safety (Safety last on left handers, but still there).

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Nick

North Wiltshire RoADAR

KenONeill

I'll try and remember my source for that one, but it was a generally reputable individual or organisation (in this context).

Tom_vRS

Thanks for that Chris. Nothing I can find to disagree with there!

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97/R BMW 328i in Boston Green.

Tom_vRS

Ken, I think your point is valid, but that would of course reduce visibility and thus require less speed - perfectly acceptable, but perhaps not completely fulfilling the criteria of "making progress".

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97/R BMW 328i in Boston Green.

ScoobyChris

Not to mention that the idiot can see and react to you sooner too.........

Chris

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Holding up the traffic in a little Italian..........

TaviaRS

Driving is about guidlines and experience. It is a foolish driver who says "that is what is says in the book, therefore that is what I shall do".

That attitude makes a number of assumptions:

1. All drivers have read the same book
2. All drivers will do as it says in the book
3. Road surfaces and conditions are uniform.

It is all very well saying "on right hand bends thou shalt stick to the left - what if the road has deteriorated? What about "marbles"? A cyclist? Ironworks? Or on a left hander - biker leaning over?

The essence of advanced driving, IMHO, is to have an array of tools in your mental toolbox and know which tool is apropriate for the situation.

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Tom_vRS

Well put that man.

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97/R BMW 328i in Boston Green.

KenONeill

Yeah, that was very much the essence of my point, particularly the bit about meeting an over-committed transplant donor on a left-hander.

tfboy

I agree with the position on the road stuff, i.e. be on left for right-handers and vice-versa.

Where I have difficulty is the limit point and always abiding to it. I'll admit firstly that I'm no saint in sticking to this, as there are a few corners I tend to go round a tad too fast to stop in time of the limit point Of course one can take evasive action, but not necessarily stop in time on your side of the road.

The other reason I tend to not stick to it is that if I did, every person behind me would be tailgating which IMHO increases the likelihood of an RTA should something occur (unfortunate but true, again imho)

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Xavier

ScoobyChris

So instead of someone driving into you, you're going to drive blindly into a bend, and hit the hazard you can't stop for?

Not had a problem myself with being tailgated into or out of bends, but if there was a car behind me, I'd be showing the brake lights earlier to help bring his speed down to an appropriate speed for the corner. By not using the limit points, he could still tailgate you through the corner which could potentially make even more of a mess should you be forced to brake......

Chris

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Holding up the traffic in a little Italian..........

KenONeill

I don't tend to have a problem with being tailgated into corners at or near the vanishing point speed, because that usually means I'm going faster than a typical tailgit thinks they can go anyway!

TaviaRS

LOL! Had something similar yesterday, man tailgitting me through a 30 limit. I think he assumed that being as I was in the mincer mobile (SLK) that I would drive like one.

One nice country road that flows with dips, crests and bends later he was nowhere to be seen. He eventaully caught up 2 miles in to the next 30 limit doing about 45 Funny thing was, I didn't go above 65 the whole way (mainly as I had the organic speed limiter fitted in the passenger seat ).

Funny what you can do.......

Had similar yesterday morning; took one of the associates out for a drive, only his fourth session & his first with me. We did a nice little 29 mile route with mainly rural roads, a bit of motorway and some urban. Took him just under an hour. I asked if he'd had a demo drive and would he like one. He hadn't and he did. Same route, more traffic and 41 minutes later we're back in the car park. He broke the speed limits - I didn't.

He now wants me as his full time tutor

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A jolly sensible Mercedes E class saloon in a rather fetching bluey grey colour. No it isn't fast, no it isn't modded, and yes, it will still eat your Fabia for breakfast.

Official mobile chicane for Briskoda trackdays

ncarring

Yeah but you're in blinkin' Derbyshire!

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Nick

North Wiltshire RoADAR

TaviaRS

We were in South Yorkshire

We have some jolly nice roads up here Nick

As to me being his tutor - his current one will get the right hump about it if I take him on my "books". Have said I'll take him out every other week though

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A jolly sensible Mercedes E class saloon in a rather fetching bluey grey colour. No it isn't fast, no it isn't modded, and yes, it will still eat your Fabia for breakfast.

Official mobile chicane for Briskoda trackdays

ncarring

I can imagine tutors would be a bit sensitive to pupils upping and decamping to another tutor. Since they (you) all give up their time for free, it'd be a bit rich for the associates to start getting choosy!

He might find, if he asks his current tutor for a demo, the results would be similar. I think all tutors should offer; mine did, and while not perhaps as progressive as some, he certainly knows his stuff and his commentary is very detailed.

My tutor wants me to have a drive with another observer before my test, for a second opinion, so there is cooperation between observers, as well.

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Nick

North Wiltshire RoADAR

TaviaRS

Indeed, that's why I was seeing him - he wanted experience of different tutors. I was the second different one to see him.

It is a good way to get used to having someone in the car who isn't your normal one.

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A jolly sensible Mercedes E class saloon in a rather fetching bluey grey colour. No it isn't fast, no it isn't modded, and yes, it will still eat your Fabia for breakfast.

Official mobile chicane for Briskoda trackdays