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This is actually WRONG! You're using 'stability' both above AND below view. That's confusing...

And I don't believe for one second that Roadcraft includes 'surface stability' in 'stability' Surface stability is within 'safety'.

Compare Roadcraft to Motorcycle Roadcraft to see this point. Roadcraft doesn't include 'stability' at all, yet clearly surface conditions and grip advantages are important to car drivers too.



Sorry. I'm surprised this one seems hard - but from my point of view you seem confused. Have you considered stability in the light of balance and counter steering?

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

I know I shall probably regret this, but I can't let it lie.

Why is it WRONG? Why CAN'T they use stability above AND below view? They do! They actually use the word above and imply it below.
One situation is more important than view and the other is dependant on view. How is that confusing........?

Situation 1 - Stability dependant on having a good view.

Fact. A motorcycle is most stable when it is upright and travelling in a straight line. The more often it can be kept in this state the better. If we reduce the tightness of a bend, the more upright we become and the more stable the machine. Being able to do this through a bend is dependant on view.

Situation 2 - Stability requiring precedence over view.

Generally, you can't get around corners by travelling in a straight line. When the bike is leant over, tyre grip faces competing demands which increases the potential for the bike to 'fall over'. If you then ride across some gravel or wet leaves or mud or metal covers or banding or horse shit - then bingo, you may loose grip and away you go! (All of those can be ridden over with much greater safety if the bike is upright, but it still applies.)

Whether you believe it or not, this IS exactly the type of 'surface stability' that Motorcycling Roadcraft and all the other advanced motorcycling organisations and individuals refer to within stability when used ABOVE view.

I refer you to p95 "STABILITY - Select a course which will provide best tyre grip" The margin references p53 - Road Surface.


You go on to suggest that, because Roadcraft makes no mention of 'surface stability', therefore the same emphasis must apply within Motorcycle Roadcraft.

Consider this:
A car normally occupies 50 - 70% of their lane. A motorcycle significantly less. This is one of the advantages we have - we are much more able to avoid these hazards. Maybe, just maybe, Roadcraft doesn't single out the condition of the road surface because, in a car, there's not so much you can do about it and there's not quite the same potential to spoil your weekend if you get it wrong.
In Roadcraft, surface condition can therefore sit quite comfortably within safety.


Finally, I don't fully understand the question considering stability in the light of balance and counter-steering.

What I do know is:
I consider stability every second I'm on my bike. I know I need to balance the machine and counter-steering is the only way I can steer my bike (above walking pace).
What am I missing here? It must be something deep such as gyroscopic effects, or something!

And yes, maybe I was premature in thinking we agree.............

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It's tricky doing nothing - you never know when you're finished

Oh dear!

Let's get right down to basics and try to get rid of the confusion.

I'll have a go at your post above next, but right now I'm going to to define the four terms that motorcycle roadcraft gives us in the 'positioning hierachy'

Safety:

This is about all the primary 'stay out of danger' things. It warns us not to come into conflict with other road users, but also warns us to manage road surface irregularities and basic grip. Without managing these things we have nothing. In fact we'd be off or dead or something nasty.

Stability:

This is about balancing the machine AND NOTHING ELSE. It's because it's about balancing the machine that it isn't needed in Roadcraft. The reason it has to be listed is because balancing the machine changes your position. The torque that causes roll as you lean (or unlean) a bike comes from the net force vector (acting from the centre of gravity) falling to one side or the other of the contact patch.

Now let's consider that in terms of counter steering. We wish to turn left. pushing the left handgrip steers the contact point to the right of the CoG. Now that the CoG is acting to the LEFT of the contact point an anticlockwise acceleration in roll is initiated - that's the left lean we need for the left turn. We're actually FALLING into the lean we desired under the force of gravity. And we're in an UNSTABLE condtion - meaning that without further intervention we'll actually continue the anticlockwise acceleration in roill until we're off.

Now notice that in order for us to countersteer we had to move the contact patch out from under the CoG. That's the position consequence of stability management. And that's why Motorcycle Roadcraft gave 'stability' it's own special entry in the position hierachy.

View.

Not much contention here - once we have established safety and stability then we can position for a enhanced view.

Reducing the tightness of bends.

I'd rather they had said 'reserves of grip' here. We all know that 'the racing line' and its cousins (late apex etc) reduce the radius of curves and enable more grip reserves at the same speed or a higher speed or both. While it isn't unreasonable to describe this advantage in terms of 'stability', doing so in this precise context seems to me to be the primary source of confusion. - How can we hope to understand the hierachy when two terms in different positions overlap? - So we MUST exclude 'stability' (as above) from this entry in the position hierachy.

Summary.

I believe that the position heirachy in BOTH Roadcraft and Motorcycle Roadcraft are well designed and correct. The absence of 'stability' in the Roadcraft version speaks volumes. Its absence EXCLUDES factors that apply to BOTH cars and bikes, while its presence in Motorcycle Roadcraft points to a specific and important 'bikes only' feature.

That said, it's pretty hard to come up with any scenario where 'stability' on bikes actually belongs outside of safety. However it is possible. One might deliberately sacrifice stability in order to avoid a crash.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Same here.

I've tried to snip to the crux. I hope that works.



Nope. These things are within 'safety' in exactly the same way that not running off the road is within safety. It's primary within safety that we avoid hazards. And drain covers and wet leaves are hazards.

Or do you really want to tell me in some bizarre fashion that SAFETY is more important than avoiding wet leaves? How could it be? Yet if 'stability' was about avoiding wet leaves then that's exactly what Motorcycle Roadcraft would be saying.



I think you're missing the position effects of balancing the machine. It's small, but it's real.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Arrgh! You're so difficult to argue against.

You have the ability to make people question their own beliefs. (Which is probably why I am backing you to win the road safety campaign).

However, I am determined to plod on (hopefully with a bit less emotion) because I still fail to reach the same conclusions as you.

I'm not used to this verbal jousting, so I shall go away and compose myself, and then I shall return with suitable responses - if only to provide you with more cannon fodder.

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It's tricky doing nothing - you never know when you're finished

Thanks.

I really do believe I have the issue 'well sorted', and I'm certainly not arguing for the sake of it. Of course you could always phone me to talk it over. I'm on 01862 893030.

I've also invited three motorcycle training specialists along to help us out.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

The animated graphic on the following page illustrates the position effect of countersteering: http://www.vsa.cape.com/~wayg/mrep/csteer.htm

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

And there was me hoping to pop in, say "Hi, not been here for a while, how ya doin? Oh, and by the way . . . "

I first heard 'Safety View Advantage' from a Hampshire traffic biker in about 1980/81. SSV a fair bit later. Not to say SSV wasn't around earlier, just I'd not heard it.

I found SVA easier to implement, it's just a matter of looking at each individual situation and deciding where on the lane width is 'safest' first - and whether a 'surface' danger is more dangerous than an 'conflict' danger.

If there is free choice of any position in the lane width, position for best view.

Advantage? Many options here, whether to ease cornering by taking a wider-radius line, or positioning to get the best move out of a junction, or perhaps make use of camber.

So, really, what I'm saying is that I use S(S)VA(S).

More here (esp. for those who like 'mantras'):

http://www.cooperbiketraining.org.uk/games/games.htm

Where In The World?
If you've recently taken a CBT or test-level course, then you will probably have been encouraged to ride about a metre out from the kerb, or in the centre of your line. Real-world riding suggests that moving across the lane width can have significant benefits - but also serious risks.

Enter, two mantras:
Safety - View - Advantage
Safety - Stability - View

It doesn't particularly matter which you use, as long as you understand what you can gain from each.

Safety. Children are warned: "Run away from danger". For you, a grown-up, thinking rider, this means keeping as far away from danger as reasonably possible, e.g. if there's a car in the junction to your left, move across to the right of your lane. If there are two hazards (add an oncoming car to the example above) then separate them either in time, i.e. change your speed so that you only encounter one at a time, or distance, i.e. go equidistant between them.

Stability. Choosing the best surface to ride on, i.e good tarmac rather than oil, gravel, horse . . . dust, or sunken drain covers.

View. See and be seen. One classic example of this is following HGVs, several of which now sport warning signs: "If you can't see my mirrors, I can't see you". Try to make eye contact with other road users; if the driver at the junction mentioned above can't see you, it's far more likely that he will pull out! A more extreme example of 'View' is positioning for corners, which is really beyond the scope of this 'game'.

Advantage. Again, this is slightly more involved, but one example is adapting your following position to overtake when leaving a bend, using the advantages of an earlier view and the bike's superior acceleration.

In the second version: Safety - Stability - View, Ask yourself how you chose the position in the lane width you're riding in. Then 'project ahead' and choose - or plan - where you want to be, rather than deciding when you get there - by which time it's really too late to decide that you really ought to be somewhere else!

Interesting that the guy thinks that a bike can be made to turn simply by shifting ones weight.

Andy Ibbot from the California Race School had the belief that this was impossible - so he modified a bike to prove it.

He built the bike with two sets of bars and duplicate controls. The additional bars are fixed and placed where the mirrors would be.

He now challenges anyone to ride the bike, take hold of the fixed bars, and do whatever they can to steer the bike. He has been doing this for years and no one has succeeded.

Anyway, don't distract me.......I'm working hard on my other reply!

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It's tricky doing nothing - you never know when you're finished

Thanks for that, Horse.

I am aware of this article, and many others which say the same.

Unfortunately, M/C Roadcraft doesn't quite put it in the same way.

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It's tricky doing nothing - you never know when you're finished

And as I'm sure you're aware, M/c R/c doesn't have all the answers. Counter-steering (indeed any steering method) being a good (bad) example.

Indeed, Dave Jones is quite vocal about this in his latest (rewritten) book. If I could find my copy I'd quote it for you.

However, I'm lucky enough to have had the benefit of non-Roadcraft training to pick and choose from.

Actually, re-reading your post, I'm not sure now what you meant.

Are you saying that my interpretation of SSV is wrong, or that you prefer SSV to SVA, or that my SSV is right (and so are others) but wrong to R/c . . .

Thanks, again.

I have a copy of the new 'Not The Blue Book'.

Dave Jones is a good man!

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It's tricky doing nothing - you never know when you're finished

No, not at all. I agree completely with you and the article. It says exactly what my beliefs are. However, my current 'debate' with Paul is centred on the wording within M/C Roadcraft - which is not expressed in quite the same way.

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It's tricky doing nothing - you never know when you're finished

Sorry, I missed this before........

I'd like to know more about what you mean - obviously you didn't go through RoSPA or the IAM, then. They both treat M/C Roadcraft as the 'bible' of motorcyclists!

M/C Roadcraft does have a few critics, and I know why, but it is pretty hard to beat.

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It's tricky doing nothing - you never know when you're finished

Nice to see you and thanks for popping along.



I expect that we all end up using very much the same hierachy but we're having a haggle about the definitions. A couple of direct questions for you, Horse, if you don't mind:

- With the variable definitions of 'stability' around do you think it's a good idea to use the term in this context?

- Why do you think that Motorcycle Roadcraft has the 'stability' term while Roadcraft does not? [Ignoring the 'flip' answers like: you can't fall off a car unless you're being very silly ]

- Can you come up with any useful scenario where safety takes precedence over stability? (And if you can't then is there any reason not to roll it into safety?)

- I notice quite a few mentions of SSV, both here and elsewhere. How has it happened that the 'advantage' term has vanished? We need that term! The clear risk of excluding it is that folk will 'jump' advantage over vision and roll it into stability. If it ends up there it's damaging and wrong - we end up preferring the racing line to good vision.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Indeed. I've seen the video.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Yep, in that Horse is agreeing with you and not me. I'm hoping to dig a little deeper - I'm still proposing that this definition arose after the event when stability was added to the Motorcycle Roadcraft hierachy.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Yeah, I was pleased (in a way) that Horse had put that article on here, but to be fair, I've known about it for ages.

I wanted to argue without re-enforcements....

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It's tricky doing nothing - you never know when you're finished

Ah well, so much for a quick pop in . . .

1. As I prefer the SVA version, I haven't really got hung up on defining stability. Sorry, not much help there . . .

2. To be abs. honest, I'd not picked up the wording diff. between the two. I'll have to dig them both out & read up.

3. Driver potentially encroaching from the left, gravel over centre & right of lane - I'd go for the safety gap. Stability might be an issue, but I would still have time to react.

4. Don't know. Guessing, I'd suggest that it may be down to whichever school particular trafpols attended, and which instr. were there at the time. There's a Thames Valley (and poss. others now) concept called 'thirds' for splitting up the distance between you & hazard - I'm not even going to try and explain it as I can't make it work for me