Major vs. marginal gains in safety

[Gimlet]

One scenario where I have become very conscious of grip is overtaking. If accelerating to overtake, I'm steady over white lines especially when wet, then when returning to correct lane always easing off brakes while crossing back, then back on brakes hard before hitting the car in front.

As a general rule I would say that unless something unforeseen suddenly happens mid-maneuver, if you're braking to get back in line after an overtake you've misjudged, distance, speed, timing or all three.
I wouldn't be accelerating hard as I cross the white line either. I cross into the oncoming lane without advancing on the vehicle I want to pass before I start hitting the throttle, so that I can see properly that the way is clear ahead and behind (no-one else has jumped the queue without looking), my object driver and following drivers can see me and my original space is still available if I have to abandon the move. Then when all is well I'll hit it and the'll be no braking involved. All that happens in a split second and overtakes are still be completed at speed but with maximum road presence and an escape route and I don't take other drivers by surprise and leave them feeling they've been strafed

[Dodgy69]

One scenario where I have become very conscious of grip is overtaking. If accelerating to overtake, I'm steady over white lines especially when wet, then when returning to correct lane always easing off brakes while crossing back, then back on brakes hard before hitting the car in front.

Is that something you learnt from bitter experience, someone else's tale of woe and glory, or something you figured out after reading and analysis?

Always interesting to know where the ideas come from.

Not sure tbh...but when im passing a line of cars one at a time, I'm often needing front brake.

[Hot_Air]

As a general rule I would say that unless something unforeseen suddenly happens mid-maneuver, if you're braking to get back in line after an overtake you've misjudged, distance, speed, timing or all three.
I wouldn't be accelerating hard as I cross the white line either. I cross into the oncoming lane without advancing on the vehicle I want to pass before I start hitting the throttle, so that I can see properly that the way is clear ahead and behind (no-one else has jumped the queue without looking), my object driver and following drivers can see me and my original space is still available if I have to abandon the move. Then when all is well I'll hit it and there'll be no braking involved. All that happens in a split second and overtakes are still be completed at speed but with maximum road presence and an escape route and I don't take other drivers by surprise and leave them feeling they've been strafed

I'm with Gimlet on this

Like Rockburner, I'm curious to know why you'd need to brake, let alone brake hard, even when passing a line of cars?

[The Spin Doctor]

One scenario where I have become very conscious of grip is overtaking. If accelerating to overtake, I'm steady over white lines especially when wet, then when returning to correct lane always easing off brakes while crossing back, then back on brakes hard before hitting the car in front.

If you're back on the brakes hard, I'd say the gap is too small. What if the surface ahead of the car you're about to be overtaking and which will be under your wheels when braking, turns out to be rubbish?

If you want to make a major gain in safety for a marginal loss in progress, pick a bigger gap, so you can glide into it rather than brake into it.

[Dodgy69]

Think it's when traffic oncoming, so I speed up my monoever, then when pulling back in needing to brake to lose speed. Not uncommon surely.

[Gimlet]

Braking to get back into lane is bad practice in my view. It can cause a chain of panic braking among following traffic which is really dangerous. If you have to accelerate so hard to get past that you have to scrub off with the brakes to get back in you've either miss-timed it, there wasn't enough space to begin with or you tried to take too many cars in one go. Miss-timing is the most common error in my view.

Furthermore sudden point a squirt overtakes can rattle the driver of the car you plan to pull in behind. They often assume you're going to pass them as well so they brake to let you by and get rid of you and if you were relying on diving back in on the brakes they can inadvertently shut the door on you. You either have to shut your eyes, breath in and pray or you're forced into taking on the braking car as well, and as you were running nip and tuck in the first place you almost certainly won't have time. Cue lots of hooting and flashing lights and cursing and possibly some uploaded dashcam footage that will come back to bite you.

[Horse]

Think it's when traffic oncoming, so I speed up my monoever, then when pulling back in needing to brake to lose speed. Not uncommon surely.

There's a couple of different ways generally used to explain how things can go wrong: 'chain' and 'Swiss cheese'.

Think of your overtaking as a chain of events:
- you're following another car, so reliant on that driver to do what you expect
- if it's a squeaky overtake, you're probably closer to the car ahead, so won't have a good view of the road surface immediately ahead
- you're close, but your attention is on judging the gap, possibly away from side turnings etc
- you're relying on correct judgement of the oncoming vehicle's speed and distance - which is difficult

And that's all before you start to overtake! Each one of those is a link of chain that could break - something that could go wrong.

If you're honest with yourself, that list of potential failure points is extensive.

[The Spin Doctor]

Think it's when traffic oncoming, so I speed up my monoever, then when pulling back in needing to brake to lose speed. Not uncommon surely.

If you need to speed up, it means you've misjudged the time / distance to the oncoming vehicle.

Yes, it's not uncommon...

...and it's not uncommonly a cause of fatal crashes.

[Dodgy69]

I think it all comes down to how purposeful your progress is.

[Gimlet]

And how fast the rest of the traffic is going. If it's under 40 mph and you're only creeping past, you're filtering.

Having said that, even when filtering I try to use space and judge timing to maintain progress without touching the brakes. Brake lights cause drivers to react. Ideally, when overtaking (or filtering) you don't want your actions to force sudden reactions from other drivers. You've read what they're doing and you need them to keep doing it until you've gone by.
Even those drivers who pull left when you're filtering aren't necessarily being courteous. More often than not its a WTF-did-he-come-from reaction.

But you know all this..

[Horse]

I think it all comes down to how purposeful your progress is.

Fair point.

Compare, for example, purposes such as:
- getting ahead of the vehicle ahead
- getting home at the end of the ride

[Dodgy69]

When I think about it...

I have come to an age (53) where tbh when your times up, it's up. I've done a stupid move and got away with it, bollocked myself in my helmet. I've also lost mate's who were riding safely, and goodnight forever.

We can minimize risk if we want, but that's all your doing. I work with a lad who, in all honesty, is a fuckin nightmare on a bike. He's over confident, and very aggressive and horrible to ride with on the road. He's come off a few times and gets away with it every time, slides down the wrong side of the road and hits nothing,
been through hedges, never more than a scratch.

I honestly don't believe in all the high viz stuff, if they ain't looking, they ain't seeing. It's all fate wrong place, wrong time.

[Horse]

I honestly don't believe in all the high viz stuff, if they ain't looking, they ain't seeing. It's all fate wrong place, wrong time.

Hi viz doesn't make much difference for overtaking

However, same applies to you. Cars are equally visible, but if you ain't seeing them, one day you will have created the wrong place and wrong time. No fate, you have decided to abdicate responsibility.

[Dodgy69]

Cheers Horse...but I believe Hi viz, Drls etc, only make you more visible to those who bother to look properly. Sorry mate I didn't see you, imo means, sorry mate I didn't look properly.

I don't suppose it can ever be proved, whether a bikers death could of been saved if he was shining brighter.

I believe our biggest life saver is how you read the road and its hazards ahead and hope you don't meet someone driving without due care.

[Horse]

...but I believe Hi viz, Drls etc, only make you more visible to those who bother to look properly. Sorry mate I didn't see you, imo means, sorry mate I didn't look properly.
... our biggest life saver is how you read the road and its hazards ahead and hope you don't meet someone driving without due care.

It's guaranteed that you will meet people driving whatever their 'normally ' is. But that might not meet your expectations. Unfortunately, you (obviously not 'you', it applies to everyone) won't know until afterwards whether it's going to be a good or bad experience, so for each and every interaction you need to approach it with the expectation that the driver might do something that you don't want them to.

It's nowhere near as simple as didn't look.

It might range from 'didn't look' through to 'looked, saw you, correctly estimated your approach speed, distance and time to arrival. The driver might also understand the handling and braking capabilities of bikes - and after all that just pull out anyway because they DGAS.

Also, looking is not seeing. The technical term for SMIDSY is 'looked, but failed too see', with a side order of 'right of way violation'.

People often see what they expect to see. Have a read:
https://www.dropbox.com/s/euud3txjhsvs1 ... v.tif?dl=0

Spin will, I hope, be along to post links for SOBS.

[The Spin Doctor]

Cheers Horse...but I believe Hi viz, Drls etc, only make you more visible to those who bother to look properly. Sorry mate I didn't see you, imo means, sorry mate I didn't look properly.

I don't suppose it can ever be proved, whether a bikers death could of been saved if he was shining brighter.

I believe our biggest life saver is how you read the road and its hazards ahead and hope you don't meet someone driving without due care.

https://scienceofbeingseen.wordpress.com/

Lots of reasons drivers look but don't see and it's not down to 'not looking properly' in most cases. From a couple of studies of crash causation I've seen, the figures are:

In around 1/5 of crashes it's 'looked but COULD NOT see' - the rider hadn't put the bike where the river could see it.
In another 1/3, it's 'looked but FAILED to see - down to the way the eye and the brain process visual information
In around 1/3, it's 'looked, saw and MISJUDGED - speed and distance perception errors

Very few crashes result from 'didn't look'.

You're right about reading the road and being aware of hazards, but when you think about the numbers, there are 40 million drivers in the UK covering billions of miles, and under 100 fatal collisions between bikes and other vehicles. Quite clearly, serious mistakes are really few and far between.

[Dodgy69]

Cheers Spin,

It's good to hear the scientific side of it, but me being a twat, question everything where i don't see obvious logic.

1/5.. could not see the bike... Is this when bike overtaking and is behind another vehicle.??

1/3.. Looked but failed to see...aka not looking properly, too casual perhaps. If the eyes and brain aren't working together, you shouldn't be driving.

1/3.. misjudged, yes, I get this one. Vehicles moving faster than expected, Not enough time, also maybe a driver fannying around instead of getting up to speed quicker when joining a main road.

I also agree that drivers turn there heads in the direction of expected oncoming vehicles, but it's what's being processed in there head that is the worry.

[Horse]

1/5.. could not see the bike... Is this when bike overtaking and is behind another vehicle.??
1/3.. Looked but failed to see...aka not looking properly, too casual perhaps. If the eyes and brain aren't working together, you shouldn't be driving.
1/3.. misjudged, yes, I get this one. Vehicles moving faster than expected, Not enough time, also maybe a driver fannying around instead of getting up to speed quicker when joining a main road.

I also agree that drivers turn there heads in the direction of expected oncoming vehicles, but it's what's being processed in there head that is the worry.

Could not see. Yes, bike filtering past a junction is a classic. Also, hidden by door pillars, street furniture, etc.
LBFTS. No, there's so many reasons why this isn't the case. Often, people see what they expect to see and look only where they expect things to be.
Misjudged. Bikes are smaller and people often don't understand them.

[Horse]

Ever considered bike choice as an influence on crash / injury outcomes?

Motorcycle fuel tanks and pelvic fractures: A motorcycle fuel tank syndrome

ABSTRACT
Objective: Pelvic injuries are a serious and commonly occurring injury to motorcycle riders involved in crashes, yet there has been limited research investigating the mechanisms involved in these injuries. This study aimed to investigate the mechanisms involved in pelvic injuries to crashed motorcyclists.

Method: This study involved in-depth crash investigation and 2 convenience-based data sets were used. These data sets investigated motorcycle crashes in the Sydney, Newcastle, and Adelaide regions. Participants included motorcycle riders who had crashed either on a public road or private property within the study areas. The mechanism of injury and the type of injuries were investigated.

Results: The most frequent cause of pelvic injuries in crashed motorcyclists was due to contact with the motorcycle fuel tank during the crash (85%). For riders who had come into contact with the fuel tank, the injury types were able to be grouped into 3 categories based on the complexity of the injury. The complexity of the injury appeared to increase with impact speed but this was a nonsignificant trend. The pelvic injuries that did not occur from contact with the fuel tank in this sample differed in asymmetry of loading and did not commonly involve injury to the bladder. They were commonly one-sided injuries but this differed based on the point of loading; however, a larger sample of these injuries needs to be investigated.

Conclusion: Overall improvements in road safety have not been replicated in the amelioration of pelvic injuries in motorcyclists and improvements in the design of crashworthy motorcycle fuel tanks appear to be required.

[Horse]

Think it's when traffic oncoming, so I speed up my monoever, then when pulling back in needing to brake to lose speed. Not uncommon surely.

Just happened across this:

Table 8 shows that, as the oncoming vehicle speed increases, the frequency of 'negative time margins' rises sharply, particularly when it is above that of the overtaken car. It was suggested that drivers were primarily using the estimated distance to the oncoming car as a cue for deciding whether or not to overtake. Another overtaking study (Kaukinen 1972) has also found that, when the speed of an oncoming vehicle was higher than that of the vehicle being overtaken, the number of erroneous overtaking judgements was highest.

It is concluded therefore that the most serious misjudgements are of approaching vehicle speed, although a major misjudgement of distance could obviously put the driver at risk. Many of these misjudgements are attributable to the innate limitations of our perceptual apparatus, since often the judgements are having to be made on vehicles at very long distances. For example, at overtaken and oncoming vehicle speeds of 50 mph, the total overtaking distance required is of the order of 1500 ft.

Perception, 1980, volume 9, pages 183-216
Vision, visibility, and perception in driving
Brian L Hills