Safe Speed Forums

What is it with you car drivers that you don't understand that when I have entered a roundabout and you are approaching it too, from my left, you enter the island without scrubbing off speed and going over the white line without the faintest idea that I DON'T KNOW IF YOU HAVE SEEN ME AND ARE GOING TO SIDE-SWIPE ME OR WHETHER YOU HAVE SEEN ME AND ARE JUST GOING TO ENTER THE ISLAND BEHIND ME!

I've been using the bike to commute the last few weeks, since the weather's been good, and I've noticed a really odd behaviour from car drivers. It happened again this morning, so I thought I'd post about it.

I came across a slow moving taxi - approx. 50mph on a NSL road - and he had 2 other cars behind him before me. The two cars were following too closely (approx. 1s gaps, no surprises there) and were clearly showing no signs of trying to pass. So, like you do on a bike, I wanted to get past Mr. taxi and get on my way, and I intended to do this by bunnyhopping up through the queue.

Now, I'm quite a careful rider I think it's fair to say. I won't squeeze past traffic in my lane, I always indicate before an overtake and I always wait for a good gap so I can pass fast and wide, so I don't see my riding as unduely aggressive or surprising. What I've noticed though, is that almost every time I do this, the car I've just passed seems to disappear to FAR more than a 2 second gap behind me, even though they were happy to follow another car at <1s. I'm not cutting in too close, I make sure of that so I really can't think of any reason why drivers do this.

Is it simply the 'surprise' of being passed by something that they hadn't seen because they'd forgotten what their mirrors are for, is it that they're being snapped out of some kind of trance-like state, or is it just that the back of my bike doesn't look very... user friendly...?

Its confused me for decades I think it may be no more than queueing mentality, the sheep that drivers are or become where they all have a focus or fixation on anything but driving, maybe your action simply wakes them up, maybe they are just over reacting by way of a gesture in their minds that only they know All I do know is that it is another example of how road users drift away from driving properly to being driven by the crowd. I dont think its just a reaction to bikes though cos Ive had it happen when Ive overtaken in similar circumstance in car .Most people do not drive anywhere, they simply habbit their way along or follow the crowd.





Have any of the other bikers noticed this?

I'm sorry, I made that mistake a few weeks back and caused the bike rider to slow. I'll try not to let it happen again.

I've become more confident and now tend to slow down more and get a smooth gear change done for roundabouts even if there is someone behind who would like me to go a bit quicker. One day I'll learn to heel and toe so I don't have to give time for the clutch to slip.

there were tests carried out on braking by a motorcycle mag where they took a sports bike and went from 100mph to zero in 5 seconds, you would be lucky to achieve that at 60 in your car.Making ref to factors like tyres, wet roads and locking the wheels are simply factors not related to the braking CAPABILITY question. If both vehs on good surface and both in competent hands then the bike would stop quicker.

What is it with you car drivers that you don't understand that when I have entered a roundabout and you are approaching it too, from my left, you enter the island without scrubbing off speed and going over the white line without the faintest idea that I DON'T KNOW IF YOU HAVE SEEN ME AND ARE GOING TO SIDE-SWIPE ME OR WHETHER YOU HAVE SEEN ME AND ARE JUST GOING TO ENTER THE ISLAND BEHIND ME!

So what would you do in my position?

Well, I slow down on the island and they look at me like "what's your problem, get on with it?" and I'm looking at them like "well how the fu@k am I supposed to know you have seen me?"

Would they take the chance if they were the vulnerable biker or cyclist? I don’t think so - or if they did they wouldn't live for very long!

(Did car-only people even understand what I'm on about just then I wonder?)

Well at least one of us car-only people understands I have to turn right at a mini roundabout on my way to work and at least twice a week I have to stop on the roundabout for someone who appears not to have seen my indicator and isn't slowing down. I get the same filthy looks as you do when they finally stop two feet past the white lines. If they just slowed a bit on the approach they probably wouldn't have to stop at all because I'd know I wasn't going to get T-boned and could keep going.

I think the likely answer to the original question is they see Sixy in a pisspot and shades come past on a fairly loud matt black bike carrying a chain and quietly say to themselves'I think maybe I'll leave this one alone'...

I think the likely answer to the original question is they see Sixy in a pisspot and shades come past on a fairly loud matt black bike carrying a chain and quietly say to themselves'I think maybe I'll leave this one alone'...

Sorry folks but I can assure you it's not X-Rated, It's off Photobucket.

Paul agreed with me but then added in his reply to me/us, (and I so wish I could find that thread now but I'll have to paraphrase), 'the hand is closer to the brain than the foot and can react much quicker"

Just another of so many gems from Paul's wealth of knowledge

Oh Photobucket says somewhere that it doesn't allow naughtiness and moderators will censor anything which is and ban the poster (Something like that I think but I'll have another look..)

Edit to add:

http://photobucket.com/terms

"Content/Activity Prohibited. You must use the Photobucket Services in a manner consistent with any and all applicable laws and regulations. The following are examples of the kind of Content that is illegal or prohibited to post on or through the Photobucket Services. Photobucket reserves the right to investigate and take appropriate legal action against anyone who, in Photobucket's sole discretion, violates this provision, including without limitation, removing the offending Content from the Photobucket Services and terminating the Membership of such violators. Prohibited Content includes, but is not limited to, Content that, in the sole discretion of Photobucket:

8.1 is patently offensive or promotes racism, bigotry, hatred or physical harm of any kind against any group or individual;

8.2 harasses or advocates harassment of another person;

8.3 exploits people in a sexual or violent manner;

8.4 contains nudity, excessive violence, or offensive subject matter or contains a link to an adult website; "


Although I'm sure some stuff gets through, so you are right really.

What's that expression about I don't know what porn is but I recognise it when I see it

If something happens and I hit the biker I will probably kill them. Possibly that they can see the rider, i.e. a person, rather than another steel box in front of them turns this into an interaction with a human being not an object.

The limiting factor for a single deceleration of most modern road vehicles (i.e. no aerodynamic downforce) is the coefficient of friction between the tyres and the road. The weight of the vehicle does not change the stopping distance as long as the brakes are big enough - that's why modern trucks can stop quickly. The difference between a Fiat Panda and a Ferrari F50 is that the Ferrari's brakes will do 60mph to zero 1G stops many times without fading. The Panda's brakes will begin to fade after five or six stops and by the tenth stop will produce loads of smoke and not much else. Both vehicles will have much the same stopping distance for the first stop. In fact the Panda may do better because the Ferrari's brakes probably need more heat before they start working properly. A modern motorbike has as much (or more) performance than the Ferrari but the same laws of physics apply to both and you can't shorten the stopping distance without extra grip, no matter how powerful the brakes are. The astounding fact is that a Panda really can do 60 to 0 in 3 seconds in ideal conditions! Of course if we increased the starting speed to 110mph (or whatever a Panda can do) the story would be very different because the Panda's brakes would begin to lose efficiency before the first stop.

Factors like tyre, wet roads and locking wheels are VERY relevant to real world stopping distances. You don't fall off cars if you lock the wheels...

That's interesting. I forgot about the aerodynamics. Bikes are pretty lousy. From high speed, I guess there would be significant retardation simply from the driver sitting up a bit (although I'm not sure about this, having never ridden a big bike quickly)!

I have to disagree with the journalist who wrote the article though! He's falling into the same trap as the Highway Code authors when he says everything can stop from 60 in about the same time! There's a LOT more to stopping a car than just the weight and the tyres! IF there weren't, worn dampers wouldn't affect stopping distances the way they do! One of the biggest factors is the centre of gravity height. In any road vehicle braked by its tyres, there is a momentum force acting to keep the car going, directed forwards through it's centre of gravity. There is the retarding force acting backwards through the tyre contact patches. Because of the vertical separation of these two forces, the weight transfers off the rear wheels and on to the front during braking. (we've all seen a car's nose dip as the brakes are applied). The less weight there is on a tyre, the less stopping force it can exert before it starts to slip. The Ferrari has a lower centre of gravity, so less of its weight transfers to the front tyres during braking. Its rear brakes can do more work before they start to cause the tyres to loose grip, so the braking is more evenly shared between the 4 wheels. Furthermore, the Ferrari won't be a nose-heavy as a front wheel drive Panda to start with - so there will be a greater proportion of its weight on the rear wheels to begin with before the braking starts. Finally, I guess a set of Ferrari tyres costs about as much as a Panda! I'd put money on them having superior braking performance!

I'd be happy to accept the author saying that "the difference in stopping distance from 60 between a Panda and a Ferrari isn't as muh as you'd think", but to say there wouldn't be a difference is simply not (in my view at least!) credible.