Cornering basics 2 Assessing a bend without the limit point

[R_U_LOCAL]

willibetz said:

Reg, thanks for the comprehensive and thoughtful response. I'm not entirely sure I agree with all of your comments, so perhaps we can explore them a bit more...

Ok Willi - I'll answer your points as best I can. Apologies in advance for using the quote system to produce such a long post, but it's the easiest way for me to answer without missing anything.

willibetz said:

R_U_LOCAL said:

You're making the mistake that many people make in thinking about cornering, and you're getting track thoughts and techniques mixed up with a road driving mentality.

Maybe... But, while I enjoy both, I am sufficiently conceited to think I'm pretty clear on the applicability of techniques.

That's fine for you, and I'm not trying to take anything away from your ability, but I'm conscious that there are many people who read these threads, with a wide range of ability and experience. If I hammer home the message about not confusing track and road techniques, it's not really personally directed at you - it's more of a general "be careful" message to the general readership.

willibetz said:

R_U_LOCAL said:

... If you're using the limit point to assess the bend, you'll be bringing your speed down so that it matches what the limit point is doing - as you get closer and closer to the limit point, your speed should continue to drop until you're happy that you've assessed the tightness of the bend correctly.

Agreed. Though, as we both accept, there are situations when you will enter a curve before it is possible to assess the tightness of the bend accurately. It's in that circumstance that I would consider trail braking. For the avoidance of doubt, in this context, I'm talking about planning your braking so that you are still tapering off the brake while beginning to turn into the corner. I'm definitely not suggesting that it's appropriate to try and maximise the use of available grip on the way into an unsighted corner on a public road. The benefit is that you can stop the car more quickly and less dramatically should the need arise, in the early portion of a bend before the limit point starts to run and you can safely pick up the throttle.

Right, I'm with you. I don't see anything wrong with your approach if it suits you - it obviously wouldn't score you any points with advanced driving examiners, but that's certainly not what my posts on here are all about. If you find a technique that suits you, then I'd say carry on with it - What I would say is that, rather than continuing to have the brakes applied whilst entering a bend that you're not 100% sure of, my preferred method would be to lose a little extra speed to compensate before the bend, rather than staying on the brakes, but I understand your technique.

I don't think I'll be taking it on myself though.

willibetz said:

R_U_LOCAL said:

However, you don't just use the limit point on the approach to the corner - it should be continually reassessed because, as you've pointed out, corners can tighten up. The Roadcraft system (if that's your chosen method) copes nicely with this by stating that if information changes (i.e. the limit point shows that the corner is tightening), then you can revert back to the start and readjust your position/speed/gear if necessary. You can't be absolutely sure about a blind corner until it starts straightening up, so you should always have this option in reserve.

So you take an educated guess at speed and gear before turning the wheel and picking up the throttle, but reserve the right to start the procedure again if information changes? I've certainly seen systematic drivers employ this technique, and I don't argue that it can be a safe approach if you have adequate grip in reserve - I cited Luxemburg, in my last reply, as the best example I can recall of a country where the road planners specialise in designing contracting radius curves on the approach to hairpins. However, I would contend that your preferred method, in the context of progressive road driving, is:

- a distortion of RoadCraft... (sorry about that!) It's not really that the information changes when the bend tightens. The bend was the same shape yesterday, and it'll be the same shape tomorrow. It's not analogous to the Spitfire landing in front of you. It's more that you decided your plan before adequate information was available. Which would be a fault if we were discussing it in the context of the approach to a roundabout.

- horribly inelegant, because your best guess plan will occasionally be wrong and need to be started over

- less progressive, because you need lots of grip in reserve to cater for those sneaky Luxemburger road planners

- less safe, because it takes longer to stop a car from an initial state of acceleration than from an initial state of deceleration.

No, it's not a "best guess" - it's an accurate assessment of the bend, based on the information - all the information - available to the driver at that time. The fact that the information can change as you enter/negotiate the bend is just a fact of life. If you're moving forwards, the information changes all the time. Even in the most seemingly constant-radius bends, you should constantly reassess the corner, just in case it throws up any surprises, but it's not guesswork.

There are times when you can get it wrong, of course, but going back to system can correct these errors. You're right - it's not elegant, but it works, and on the odd occasion where the information does change, compared with your initial assessment, then it'll sort the problem out.

willibetz said:

R_U_LOCAL said:

Staying on the brakes into a corner until you're sure of how tight a bend is has a couple of problems.

Firstly, it will often mean that you're then taking a lower gear to suit your speed, whilst you're still turning the wheel. This isn't ideal - I always like to have speed and gear completely sorted out before entering a corner to maintain maximum balance through the corner.

Interesting point. If a gearchange is necessary, I accept that you would need to employ another circuit technique - the heel and toe gearchange - or confine yourself to a car with an SMG gearbox

While I accept that you may not be allowed to train or drive using these methods in your club, I genuinely believe that this is an area where race driving techniques can be beneficially applied to road driving.

I'd be interested in your thoughts, and thanks again for the opportunity to discuss it.

WilliBetz

Not having a dig at my M3 are you Willi? I'll have you know it's an SMG1, so I still have to take a hand off the wheel to change gear!

Again, I see nothing fundamentally wrong with heel/toe gearchanges if you're comfortable with it and you can do it safely. I've never taught it, as the courses were never long enough, and the course curriculum never required it, but it's something I'll do myself, on occasion, if I'm having a bit of fun in the MX-5.

It's simpler, though, for less experienced or skillful drivers to start with sorting out speed and gear before the bend. If they then choose to move on from there to your methods, then fine.

[StressedDave]

R_U_LOCAL said:

Unfortunately, as I've said before, baffling people with science isn't the best way to put basic principles across. You've picked some points to argue with which we actually agree on - take this one for example...

You have to make it as simple as possible, but not too simple that you're overgeneralising. Just because you find it baffling, doesn;t mean that everyone else does. I know of at least one poster here who would feel shortchanged if I didn't use a little bit of science rather than the 'trust me I'm an instructor' method.

Reg said:

Of course it depends on the car, as it depends on countless other variables, but being specific about how much throttle in which cars would take up all the sites bandwidth - which is why I simply said "enough" throttle - surely people can work out what I mean from that? No-one expects to be told exactly how much throttle to apply, and without advanced electronic displays, I'd struggle to tell the difference between 20% throttle and 40% throttle.

Me to, and if I had an electronic display I wouldn;t use it. I tend to work on the 'listen for the pitch of the engine to change'

Reg said:

I have to take issue with this though...

StressedDave said:

I did a race engineering course a couple of years back, and one thing that stuck in my mind was the comment "80% of your lap time comes from the first 5 metres of a corner". It's as valid on the road as it is on track

I don't see the relevence at all. Lap times and entry speeds have no relevence on the roads whatsoever.

Replace the term 'lap time' with the phrase 'ability to make progress', and you'll get the gist of what I meant. I wasn't talking about entry speeds or cornering close to the limit of adhesion. I think of road driving as consisting of getting from A to B at a sane and sensible pace while using as little of the reserves of grip as possible for a given situation. Getting the entry speed right for your level of ability so that you can get the cornering line right means you can make that sort of progress without the 'oops' moments or your passenger reaching for the FM handle.

Von is right - you have a short period of time and a widely varying degree of talent in your customer pool. You have to go for a system that can consistently deliver the results that your overlords desire. The rest of the general public aren't under such constraints and are free to experiment with all manner of techniques that may work for them and in some cases can give better progress in the hands of a suitably talented driver (listening for the shuffles as the readers of PH shift themselves into the 'suitably talented' pile).

Edited by StressedDave on Thursday 5th April 14:26

[willibetz]

R_U_LOCAL said:

Ok Willi - I'll answer your points as best I can.

Many thanks - much appreciated. Genuinely interested to compare thoughts, and I take your point about the context of the discussion.

I certainly wasn't having a go at your M3, by the way. I think they're great. As to the SMG gearbox, I think you'll know where I'm coming from when I say that I don't disagree with it but don't think I'll be taking it on myself...

WilliBetz

[R_U_LOCAL]

StressedDave said:

You have to make it as simple as possible, but not too simple that you're overgeneralising. Just because you find it baffling, doesn;t mean that everyone else does. I know of at least one poster here who would feel shortchanged if I didn't use a little bit of science rather than the 'trust me I'm an instructor' method.

I can’t see anywhere where I’ve overgeneralised. Don’t get me wrong – I’m happy to accept criticism – I wouldn’t have started posting this stuff in a public forum if I wasn’t, but I really can’t see where I’ve overgeneralised anywhere. If you could point out where I have done, it’d be easier to answer the criticism.

Conversely, I do think you have a tendency to overcomplicate things, but at least I’ve specified exactly where, so you know which points I mean.

I'm not baffled by your posts either, but I'm sure a lot of other readers will be.

And I can’t remember anywhere where I’ve written “trust me, I’m an instructor”. Again, if you could point out where I’ve said that, it’ll be a great help.

StressedDave said:

Replace the term 'lap time' with the phrase 'ability to make progress', and you'll get the gist of what I meant. I wasn't talking about entry speeds or cornering close to the limit of adhesion.

If that’s the case, then you should be more careful to write exactly what you mean. As I’ve just mentioned in a recent post, there are a lot of people with very varied skills and experiences who read this forum, and I don’t want them getting mixed up between track skills and road skills. Some track skills are perfectly transferable, but others need a good grounding in basic road skills first.

Have a look back at the thread title – “Cornering basics”. I’m not really sure how I could have made that any clearer.

[StressedDave]

R_U_LOCAL said:

I can’t see anywhere where I’ve overgeneralised. Don’t get me wrong – I’m happy to accept criticism – I wouldn’t have started posting this stuff in a public forum if I wasn’t, but I really can’t see where I’ve overgeneralised anywhere. If you could point out where I have done, it’d be easier to answer the criticism.

Conversely, I do think you have a tendency to overcomplicate things, but at least I’ve specified exactly where, so you know which points I mean.

I'm not baffled by your posts either, but I'm sure a lot of other readers will be.

And I can’t remember anywhere where I’ve written “trust me, I’m an instructor”. Again, if you could point out where I’ve said that, it’ll be a great help.

You haven't, I'm just used to dealing with people who seem to want exact answers to everything, so I'm used to having to give them the full story without any tedious bits or unimportant bits removed. Nine years of dealing with barristers without a scientific background tends to do that to a man. That and having to challenge every statement where the science is either wrong or being wrongly explained. I'm sure I'll get over it in time... It wasn't a pop at you, more an explanation of why I'm wired the way I am. Sorry if you thought I was in any way disrespectful of your posting.

StressedDave said:

Replace the term 'lap time' with the phrase 'ability to make progress', and you'll get the gist of what I meant. I wasn't talking about entry speeds or cornering close to the limit of adhesion.

If that’s the case, then you should be more careful to write exactly what you mean. As I’ve just mentioned in a recent post, there are a lot of people with very varied skills and experiences who read this forum, and I don’t want them getting mixed up between track skills and road skills. Some track skills are perfectly transferable, but others need a good grounding in basic road skills first.[/quote]

Sorry, it was a quote, hence the quotation marks. I was multi-tasking (I know it's a bit of an oxymoron for us males) at the time, hence the relatively short reply. I would have thought the majority of people on here are suitably intellectually equipped to be able to make sense, or at least ask for further clarification if they don't understand.

At the end of the day it's a discussion forum - the people who read this want to discuss something, and possibly stuff that is an extension beyond Roadcraft. I could pretty much guarantee that no matter what ever you or I put in a post, someone, somewhere is going to misinterpret it and trying to police what is written so that noone could be in any way confused or misinterpreted is like trying to herd cats.

[R_U_LOCAL]

Don't get me wrong Dave - I love a good debate, and I didn't feel disrespected. We all have something to add to the discussion, and I'm happy to admit if I'm wrong about something. I just like people to be a bit more specific, that's all.

I just think it's a subject which benefits from simplifying rather than complicating. I like to show people that there's no real "black art" to advanced driving, and that these are skills that can be learned by anybody. It is interesting to look more scientifically at what's happening to a car under different situations, but sometimes, you've got literelly a few seconds to take in information, process it, formulate a plan, together with one or more contingency plans, whilst also looking ahead to the next hazard and the one after that.

In those situations, the simpler the explanation, the better, as long as that simplification doesn't go too far and leave the driver in doubt about what to do.

Plese don't stop challenging me - it keeps me on my toes.

[StressedDave]

R_U_LOCAL said:

I just think it's a subject which benefits from simplifying rather than complicating. I like to show people that there's no real "black art" to advanced driving, and that these are skills that can be learned by anybody. It is interesting to look more scientifically at what's happening to a car under different situations, but sometimes, you've got literelly a few seconds to take in information, process it, formulate a plan, together with one or more contingency plans, whilst also looking ahead to the next hazard and the one after that.

No disagreement here, although getting the stage where it all looks so easy is the hard part. I do think more visuals are the key, and so (if youtube has finally finished processing) is a small snatch of video to add to the mix:

www.youtube.com/watch?v=1dGVt8b5v1k

It's just two corners, but you can see what was happening behind the scenes as it were...

Edited by StressedDave on Thursday 5th April 21:46

[7db]

Hmmm. Funky steering graphic. My version doesn't have that.

Steering and power applied together in both of those, although in first corner there's a dip downhill so power probably not necessary for balance.

On second uphill corner, power and deflection go on at the same time. Is it Reg driving?

[gdaybruce]

OK, time to get pedantic; something that we hardly ever see on this forum!

It seems to me that that throughout this topic one very basic element of safe driving has gone unmentioned. So basic that I gues everyone is taking it for granted, but it's bugging me. While there has been much discussion about the field of view ahead and the possibility of hidden hazards behind the hedge, etc., no one has mentioned checking the rear view mirrors and making certain that ther isn't a biker (for example) coming up your outside at the point you're about take an offside line.

There, I've said it and now feel much better!

[StressedDave]

7db said:

Hmmm. Funky steering graphic. My version doesn't have that.

You had the early version where the orange slider indicated steering angle. I did a bit of work with the developers and came up with a proper steering wheel...

7db said:

Steering and power applied together in both of those, although in first corner there's a dip downhill so power probably not necessary for balance.

On second uphill corner, power and deflection go on at the same time. Is it Reg driving?

For all my protestations about how I like to get power on before steering, I do find that the tighter the bend the more simultaneous the application gets. Although I'm fairly sure that elsewhere in the video there's some trail braking entries as well...

[R_U_LOCAL]

That's an interesting video Dave - makes my amateurish efforts look a liitle poor by comparison.

I'm in the process of devising a camera mount for my car so you can compare techniques, but I'm afraid you'll have to listen to the engine to see when I'm applying the throttle.

I can't say it'd be any different than in your video though.

[7db]

StressedDave said:

For all my protestations about how I like to get power on before steering, I do find that the tighter the bend the more simultaneous the application gets.

which is why

StressedDave said:

I know of at least one poster here who would feel shortchanged if I didn't use a little bit of science rather than the 'trust me I'm an instructor' method.

To stand on the shoulders of giants, first make sure your giant is standing on something.

[StressedDave]

R_U_LOCAL said:

That's an interesting video Dave - makes my amateurish efforts look a liitle poor by comparison.

I'm in the process of devising a camera mount for my car so you can compare techniques, but I'm afraid you'll have to listen to the engine to see when I'm applying the throttle.

I can't say it'd be any different than in your video though.

A fixed mount makes all the difference. You do have to watch for vibration of the arm you attach the camera to (if you're using a camcorder IYSWIM), but other than that it's normally fine. With that video, I had a standard DV camcorder bolted to the roll bar (and no passenger). You're right about the telemetry adding another dimension though - there's no escape!