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mowgli
23rd February 2009, 08:29
Recently four work acquaintances were out riding and encountered pea gravel on a bend. A car following reckoned they weren't going fast. Three out of four lost it in the gravel and left the road. The only damage was to pride and plastic.

Today I read about the tragic death of a rider that hit oil. The same slick downed three other bikes that were riding with him, injuring one of the riders quite badly.

In the first case I thought gravel coming, slow down. Brake hard before, coast through. Watch the road not the guy losing it in front of you. You'll be right. I figured there's a good chance I'd be okay if I found myself in a similar situation.

This latest case has me spooked. Oil on the road in small patches stands out well enough. But an entire 4l container spread across both lanes might be too uniform in appearance to stand out at all. The first indication of something going awry might be the rider in front going down.

This has made me reconsider what is a safe following distance on a bike. Following a car I tend to sit well back (2sec or more) until i can get in front. I sit back mainly because I get a better view of the road ahead and have a better chance of reacting to hazards and picking a viable escape - space equals time.

When group riding I tend to ride offset to the rider ahead (staggered) and probably 1-2 secs behind. It feels safe because I have a mostly unobstructed view of the road ahead. I'm now thinking this feeling is flawed. If the rider in front goes down due to something unseen on the road surface then there's almost no chance to react before I'll be over the same hazard.

I'll be increasing my following distance, particularly on other riders, from now on.

Finally, I am not suggesting in any way that the riders in either example were following too close. I wasn't there and don't know the specifics. However, their offs have made me consider that my following distance may be too close for safety.

MSTRS
23rd February 2009, 08:40
This latest case has me spooked. Oil on the road in small patches stands out well enough. But an entire 4l container spread across both lanes might be too uniform in appearance to stand out at all. The first indication of something going awry might be the rider in front going down.



This situation would have been unavoidable, no matter what your following distance was. The oil slick was all-but invisible. And it was across both lanes. You can't avoid that, or what you can't see.
It happened just before 9pm, so it as nearly dark.
In that situation, even with a greater following distance, you would have seen the lead bike go down, you would have slowed ready to stop, hit the oil and gone down too.

Grahameeboy
23rd February 2009, 08:54
Oil is a different matter as he says.

Gravel...not panicking and staying relaxed is best and of course not braking or shutting down....

I was doing 150k's last year on SH16..just caught the white line on a straight and back end stepped out...whole bike wobbled like Mstrs belly (if that is possible)..I just relaxed..spread my legs out (!) for balance and after about a few hundred metres I slowed and carrried on...if I had pannicked I reckon I would have tumbled.

vifferman
23rd February 2009, 09:00
Three metres is a safe following distance: one metre to react, and two metres to stop in.


Or is that 'seconds'...?
Minutes? :confused:

Grahameeboy
23rd February 2009, 09:04
Three metres is a safe following distance: one metre to react, and two metres to stop in.


Or is that 'seconds'...?
Minutes? :confused:

What the.....at 50kph...braking distance including thinking distance is 15 metre's....

Grahameeboy
23rd February 2009, 09:08
I never understand the 2 second rule.

My bike does 0-60 in 3.2 seconds...if I was following a car at 2 seconds..(I mean how do you work that out anyway) and it braked...lets count...1...and...2...bang

awayatc
23rd February 2009, 09:10
oil on road is biggest nightmare for any biker anytime......
Very sad story.
My sincerest sympathy for those concerned.

regarding your question about safe distance........
Accident ,is collission ,is lack of distance......,
The bigger the distance in any direction, the more time you have to take any sort of action to avoid collissions....

Overall the following distances are far to close......
Been in a few group rides, and bikers generaly follow each other far to close.
One bike has a wheel lock up,dog running into him, or whatever, one or more of his following bikemates will pile up into it....
You will always be safer with BIG distances....Car or bike.
I stay at the rear of the pack, at least a 100 mtrs or more behind anything or anyone....
And I will pass anything if I got somebody sticking to close to my arse....

awayatc
23rd February 2009, 09:19
I never understand the 2 second rule.

My bike does 0-60 in 3.2 seconds...if I was following a car at 2 seconds..(I mean how do you work that out anyway) and it braked...lets count...1...and...2...bang

I am with you on this one....
I am supposed to rely on staying alive by reacting in 2 seconds.......
So if I check my....speedo....watch....oil pressure...., mirror and something mayor happens in front of me, I have Less then 2 seconds from "ouch"....?

Bullshit. ....I like a bit more notice, and start dropping my anchors a bit more leisurely....
Call me what you like, but I am still accident free,after over 30 years riding and driving all over the world......
And no I don't ride like a nana....

Ok sometimes I do..

Grahameeboy
23rd February 2009, 09:23
I am with you on this one....
I am supposed to rely on staying alive by reacting in 2 seconds.......
So if I check my....speedo....watch....oil pressure...., mirror and something mayor happens in front of me, I have Less then 2 seconds from "ouch"....?

Bullshit. ....I like a bit more notice, and start dropping my anchors a bit more leisurely....
Call me what you like, but I am still accident free,after over 30 years riding and driving all over the world......
And no I don't ride like a nana....

Ok sometimes I do..

Me to....

Just shows why driving standards in NZ are so bad when this is the kind of stuff the LTSA tell us...like the "merge like a zip"...which doesn't allow for the 2 second rule....

vifferman
23rd February 2009, 09:34
I never understand the 2 second rule.

My bike does 0-60 in 3.2 seconds...if I was following a car at 2 seconds..(I mean how do you work that out anyway) and it braked...lets count...1...and...2...bang
Reaction time is something like 0.4 seconds (average), so that gives you 1.5 seconds to slow down to the same speed as whatever you're following.

You work it out like this: when the vehicle in front of you passes something (road marking, pothole, post on the side of the road, crashed bike, etc.), you start counting: "one-thousand-and-one... one-thousand-and-two". If you pass the same point before you finish your counting, you're following too closely.

Three seconds for wet weather conditions.

In D'Auckland, you follow another vehicle at less than one vehicle length, to stop other bastards stealing your place in the mobile queue.

Grahameeboy
23rd February 2009, 11:23
Reaction time is something like 0.4 seconds (average), so that gives you 1.5 seconds to slow down to the same speed as whatever you're following.

You work it out like this: when the vehicle in front of you passes something (road marking, pothole, post on the side of the road, crashed bike, etc.), you start counting: "one-thousand-and-one... one-thousand-and-two". If you pass the same point before you finish your counting, you're following too closely.

Three seconds for wet weather conditions.

In D'Auckland, you follow another vehicle at less than one vehicle length, to stop other bastards stealing your place in the mobile queue.

That idea is bollocks....what's wrong with distance method as used by UK Highway Code which is tested...neither factor's in tyre tread etc but te counting method is too dodgy.

In Auckland they still cut you up...had a car alongside me once trying to get in my lane...

XP@
23rd February 2009, 12:31
If it is your mate in front, you want all the time in the world!

First you have to process the horror enfolding in front of you. This is especially hard if you know the person, "OH SHIT, WHAT THE FU*K HE'S DEAD" is usually the first thing that comes to mind, even with a small off.

We often tend to fall off on a bend. So if the rider in front of you is coming off on the same bend as you are just entering you will then need to stop on the same bend. Not easy stopping when cranked over so you have to sit the bike up before you can think about really hitting the anchors. Oh, and hope you have enough room to avoid oncoming vehicles, scenery and the fallen bike. In the case of a head-on things (cars, bikes and people) stop pretty fast.

This is where the following distance comes in to play... The more time you had up front the more options you will have at the end. From my experience 1 second is NOT ENOUGH.

My stopping power on a left hand bend which was adverse camber and the crown of a small rise was not fast enough. And there were few escape routes, bike, car and rider fully blocking the road. My easiest route, without becoming part of the scenery was Andre's knees. I didn't know if I could stop, i probably could not so before I hit him I released the brakes and gave a little throttle.

I rode away and Andre limped a bit for about 2 weeks. Not bad for a head on at about 50kmph.
http://picasaweb.google.com/ExPatty/Andre#5101815544279415778
http://picasaweb.google.com/ExPatty/Andre#5101815797682486258
http://picasaweb.google.com/ExPatty/Andre#5101816733985356850

awayatc
23rd February 2009, 13:31
well xp@, I would quite happily ride with people like you......

SPman
23rd February 2009, 14:32
The 2 second rule is a recomended minimum and also adjusts for speed.
I tend to use it as a guideline and work from there, depending on conditions, etc.
Shit - it provides a lot more space than most noddys allow!

Ixion
23rd February 2009, 14:58
There seems to be a great deal of confusion about a simple subject. The "two second rule" is not really a rule at all, it is a guideline.

the *rule* is clear . you must be able to stop in the clear distance ahead (half that on an unlaned road). The 'two second rule' and its predecessor the 'car length per' are simply guidelines to assist you.

Can you stop safely in the bit of road you can actually see? Before hitting anything ? Yes ? Ok. No ? Slow down. Simple as that

Transalper
23rd February 2009, 15:04
well xp@, I would quite happily ride with people like you......So would I, decent following distances AND a Transalp.

newbould
9th April 2009, 21:32
There seems to be a great deal of confusion about a simple subject. The "two second rule" is not really a rule at all, it is a guideline.

the *rule* is clear . you must be able to stop in the clear distance ahead (half that on an unlaned road). The 'two second rule' and its predecessor the 'car length per' are simply guidelines to assist you.

Can you stop safely in the bit of road you can actually see? Before hitting anything ? Yes ? Ok. No ? Slow down. Simple as that

The difficulty is knowing how quickly you can stop - time or distance. So I did a little experiment! I have a straight stretch of road close to home and it is a quieter road, So I tootled along at 60 and as I pass through a fire hydrant road mark slam on the anchors to proactice my emergency stop. After 3 attempts I now know my stopping distanmce from 60 k. Interesting bit is when I ride through and don't stop I count from the fire hydrant "one thousand and one, one" and I have passed the point where I end my emergency stop. Add in reaction time and from 60 k it takes me just under 2 s to stop. So if I am following a vehicle at 60 k and it suddenly hits a brick wall that neither of us happened to see I might just stop in time before hitting it if we are travelling at 60k. But if the incident isn't the sudden and unfair appearance of a brick wall (who said life had to be fair) in the road then the vehicle in front will surely take some time and space to slow down - my safety margin.

The theory now goes that at higher speeds the 2 second gap will be a lot longer than at 60 k but should still be long enough to stop?????:blink: well at least react adequately to deal with anything less than the sudden and unfair appea.............

So next stop SH1 to check my stopping distance and time from 100 kph Anyone care to jon me for the rush?

scumdog
9th April 2009, 22:15
Three metres is a safe following distance: one metre to react, and two metres to stop in.


Or is that 'seconds'...?
Minutes? :confused:

Only if you happen to be SkidMark..

wickle
10th April 2009, 21:16
I stand to be corrected but I believe recommend distance is four metres for every 10kmph. I myself believe in mim of two second rule and dont ride with people that what to play tag with my back wheel.

Patch
10th April 2009, 21:38
If you can smell his fart - you maybe sitting a little too close

If you can reach out and touch him then you're definately too close