Offsiding and straightlining - cut from 'Tailgating' thread
Posted: Tue Dec 17, 2013 5:38 pmPulled out from the other thread rather than derail it.
Background:
Can I start with a few words and ideas to consider:
And a definition or two (mine, not quotes) . . .
Perhaps best start with a few questions:
What is the main 'gain' from offsiding on the approach to a corner? Probably additional view. So that view must be required into dead ground, blind, hidden by the nearside of the corner.
What are you going to do with that additional, earlier view? This is where I think the errors may creep in for some, as they use the additional view to add (or maintain) speed, rather than remembering that they may well have to regain the nearside of the road. If that happens, then you're back to your original view, stopping distance and stopping time. Worse, the action of returning to the nearside will require steering into the turn on a tighter line, then returning to a 'normal' cornering line (as required for whatever you've identified) - in other words manouvering at your original 'smooth line' speed.
The additional view *might* show you the exit sooner - but if it's a blind bend with no other clues, shouldn't you presume worst case rather than continue into the bend on the offside?
Back to view; that works both ways. It also means that any oncoming driver sees you sooner. The question - which can never be answered - is 'How will that driver react?'. if they move to their right to avoid you, then your problems have just multiplied . . .
More on 'view': what view do you gain Vs where is the danger? If the danger is in a blind corner, then you have two vanishing points: the one where the 'kerbs meet'? (Which is actually, in a left bend, showing you the far kerb as the limit, you actually need to be looking where the left kerb meets the centre line, as your longest stopping distance in clear view on your side of the road. But . . . that is actually beyond the second, 'hidden', vanishing point - the surprise horizon just around the left kerb.
So extending view by offsiding could easily lull someone into a false sense of security over their stopping distance - and that could lead to temptation over speed . . .
[FWIW, IMHO many people are optimistic anyway over corner entry speeds, in particular the lead time ahead their vision provides]
If I do it, I'll return to the nearside while still on the straight approach (possibly that 'straight' is across lanes).
That's for two-lane roads. I think many people really push their luck on single lane width country roads with blind bends, positioning well over to the offside verge. My preference is to abandon a 'proud' position and - in extreme circumstances - keeping to the nearside (but sacrificing speed too, obviously). The argument I've heard is that the extended position gives better views - but, again, of what? If it's an oncoming vehicle what will the driver do? Also, many lanes have gravel etc. along the centre; keeping to the left wheel track means a firm surface is available for braking, rather than trying to steer and brake together.
Straightling, subject to a clear view of the offside verge etc., I'll happily do if there's a gain without safety loss, albeit not if it will confuse following drivers.
'More'?
Yes, the elevated riding position does help view. However, it's not as simple as just 'grip', it's all the laws of physics which act on bikes in awkward ways. Only very recently has an ABS which works in corners been developed for bikes. Combining braking and steering is possible, but uses available grip sooner.
And, yes, perhaps it should be in here:
viewtopic.php?f=9&t=4466
Background:
Horse wrote:TR4ffic wrote: As an AD, can you see a scenario where you end up on the wrong side of a decision because those ‘judging’ you fail to see (understand) what you were doing/attempting to do… Where you effectively end up being penalised for having a driving standard higher than that of the general populous.!?
The theme then moves to an ever-recurring question: what sets AD apart from 'DSA L'? . . . what 'actions' form a distinction between the two levels, and how can they be specified (for training) and assessed (for tests)?
The one which springs to mind is use of the road width, typically positioning for corners. . . . I'm not a great fan of offsiding for view, although I do 'straightline' when safety and view permit.
Grahar wrote: Given that you are a very experienced advanced driver/trainer/rider I am curious to know why you are not keen on offsiding? Am I right to perceive that you only ever off-side to 'straightline'?
Can I start with a few words and ideas to consider:
- Proactive, respond Vs reactive
Stopping distances (and time taken) Vs forward view (in seconds)
Implications for other road users
Intentions, potential gain
Potential unintended consequences
And a definition or two (mine, not quotes) . . .
- Offsiding: moving beyond the centre line (real or perceived) to gain view or stability (through the corner, not to avoid very poor road surface), on the approach to or through a corner [note: deliberately omitted 'safety' here, as in moving away from greater danger]
Straightlining: moving beyond the centre line when a clear view of the full road width is available
Perhaps best start with a few questions:
What is the main 'gain' from offsiding on the approach to a corner? Probably additional view. So that view must be required into dead ground, blind, hidden by the nearside of the corner.
What are you going to do with that additional, earlier view? This is where I think the errors may creep in for some, as they use the additional view to add (or maintain) speed, rather than remembering that they may well have to regain the nearside of the road. If that happens, then you're back to your original view, stopping distance and stopping time. Worse, the action of returning to the nearside will require steering into the turn on a tighter line, then returning to a 'normal' cornering line (as required for whatever you've identified) - in other words manouvering at your original 'smooth line' speed.
The additional view *might* show you the exit sooner - but if it's a blind bend with no other clues, shouldn't you presume worst case rather than continue into the bend on the offside?
Back to view; that works both ways. It also means that any oncoming driver sees you sooner. The question - which can never be answered - is 'How will that driver react?'. if they move to their right to avoid you, then your problems have just multiplied . . .
More on 'view': what view do you gain Vs where is the danger? If the danger is in a blind corner, then you have two vanishing points: the one where the 'kerbs meet'? (Which is actually, in a left bend, showing you the far kerb as the limit, you actually need to be looking where the left kerb meets the centre line, as your longest stopping distance in clear view on your side of the road. But . . . that is actually beyond the second, 'hidden', vanishing point - the surprise horizon just around the left kerb.
So extending view by offsiding could easily lull someone into a false sense of security over their stopping distance - and that could lead to temptation over speed . . .
[FWIW, IMHO many people are optimistic anyway over corner entry speeds, in particular the lead time ahead their vision provides]
If I do it, I'll return to the nearside while still on the straight approach (possibly that 'straight' is across lanes).
That's for two-lane roads. I think many people really push their luck on single lane width country roads with blind bends, positioning well over to the offside verge. My preference is to abandon a 'proud' position and - in extreme circumstances - keeping to the nearside (but sacrificing speed too, obviously). The argument I've heard is that the extended position gives better views - but, again, of what? If it's an oncoming vehicle what will the driver do? Also, many lanes have gravel etc. along the centre; keeping to the left wheel track means a firm surface is available for braking, rather than trying to steer and brake together.
Straightling, subject to a clear view of the offside verge etc., I'll happily do if there's a gain without safety loss, albeit not if it will confuse following drivers.
7db wrote:Is that a bike thing? They seems to have move view than grip, whilst the rest of us are languishing with more grip than view.
'More'?
Yes, the elevated riding position does help view. However, it's not as simple as just 'grip', it's all the laws of physics which act on bikes in awkward ways. Only very recently has an ABS which works in corners been developed for bikes. Combining braking and steering is possible, but uses available grip sooner.
And, yes, perhaps it should be in here:
viewtopic.php?f=9&t=4466
