Speeding cyclists

"[Not Responding]" <[email hidden]> wrote in
:"]news:[email hidden]:

Quoted message said:

Getting peds off the streets after 1 pint seemed to be precisely their aim.

Yep, get them back in their cars where they belong!

Graeme

David Hansen said:

On Sun, 22 Feb 2004 17:42:59 +0000 someone who may be "Just zis Guy, you know?"
<[email hidden]> wrote this:-

Quoted message said:

Quoted message said:

Or write to the Chief Constable asking whether this is policy as it does not appear to have any
legal authority. Then at least they might take notice >>and change policy.

Who else do you think the letters would have been addressed to? ;-)

MP. I would use the line, "who makes the law, you or the officials that are supposed to
enforce it?"

Found on web, half remembered and url forgotton.

Some research on blood alcohol level of crash victims:

most drunk (on average); pedestrians, next most drunk; car passengers, next: car drivers, most sober
by quite a margin; cyclists.

can't find it again. Damn.

DavidR said:

"Trevor Barton" <[email hidden]> wrote

Quoted message said:

If I had a choice between being hit by a car at 20mph or a bike at the same speed, it'd be the
car any day. Well, assuming that is, I didn't have any other choice 😉

Even a direct hit is below the waist. Above the waist the rider must be softer than a windscreen.

Quoted message said:

Of course, if I had the same warning of the impact, withing bounds I'd be better off with the
bike because it's narrower and I'm more likely to be able to avoid it by jumping out of the way,

...and the rider has more sideways room...

... And a hellofa lot less manoeverability ...

Quoted message said:

...and the rider has more incentive not to hit you.

You would do less to avoid hitting a pedestrian when in a car than when on a bike??

Quoted message said:

Below 20mph I can outbrake any car. 30mph plus is admittedly less easy (though at that speed I am
unable to make a comparison using a flat road).

I'm not sure you can. Below 20mph braking times are quick either way (to a halt) Reaction times are
liable to be very very significant as they are a fixed period irrespective of speed, ie at 70mph
the reaction time is only a small proportion of the total *time* to a halt, whereas at 20mph they
are far more significant. At 70 they make a far more significant difference to the *distance*
required to stop.

Quoted message said:

Quoted message said:

but that's *still* not an argument for knowingly speeding on a bike.

True.

Quite.

--
Trevor Barton

in message <[email hidden]>, Trevor Barton

(') said:

DavidR said:

"Trevor Barton" <[email hidden]> wrote

Quoted message said:

If I had a choice between being hit by a car at 20mph or a bike at the same speed, it'd be the
car any day. Well, assuming that is, I didn't have any other choice 😉

Even a direct hit is below the waist. Above the waist the rider must be softer than a windscreen.

Quoted message said:

Of course, if I had the same warning of the impact, withing bounds I'd be better off with the
bike because it's narrower and I'm more likely to be able to avoid it by jumping out of the way,

...and the rider has more sideways room...

... And a hellofa lot less manoeverability ...

Don't think so. I'm pretty confident an average bike at 20mph can out-turn an average car at 20mph.
Certainly on my mountain bike at 20mph I can negotiate bends I couldn't negotiate in a car at all.

Think about it, if you're leaning your bike at 45 degrees through a bend you're sustaining 1g
laterally. A bike on any reasonable surface can do this. The number of cars which can handle a 1g
turn without spinning out is pretty limited. Maybe a Lotus Elise, but nothing less.

--
[email hidden] (Simon Brooke) jasmine.org.uk~simonOpen ↗

;; in faecibus sapiens rheum propagabit

Trevor Barton said:

Bikes have pointy bits.

[...]

Quoted message said:

If I had a choice between being hit by a car at 20mph or a bike at the same speed, it'd be the car
any day.

Then you are a fool. All this nonsense about 'pointy bits' ignores the fact that the vast bulk of
the energy/momentum is carried by the soft squidgy rider. The 'pointy bits' will only do any real
damage if they are pushed into you by the mass of the rider, which is just about theoretically
possible but hardly a likely scenario. An impact with a car at 20mph has a significant chance of
_killing_ you.

James

Trevor Barton said:

Quoted message said:

...and the rider has more sideways room...

... And a hellofa lot less manoeverability ...

Than a car? What planet are you on? If a pedestrian is in the middle of the cariageway, then a car
won't be able to miss them whatever it does, whereas a bike has a choice of which side to pass on.

Quoted message said:

Quoted message said:

Below 20mph I can outbrake any car. 30mph plus is admittedly less easy (though at that speed I am
unable to make a comparison using a flat road).

I'm not sure you can. Below 20mph braking times are quick either way (to a halt) Reaction times
are liable to be very very significant as they are a fixed period irrespective of speed,

The fixed period is very different for moving a foot from accelerator to brake, than for pulling a
brake lever which is already under the fingers.

James

James Annan said:

Trevor Barton said:

Bikes have pointy bits.

[...]

Quoted message said:

If I had a choice between being hit by a car at 20mph or a bike at the same speed, it'd be the
car any day.

Then you are a fool.

Yeah, whatever.

"Trevor Barton" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

I'm sure that that is correct given sufficient warning. However I'd suggest that you can start a
car turning far faster than you can a bike at 20 mph. You only have to turn the wheel to the side,
and it turns immediately at its maximum g.

On a bike, you have to lean and steer, and the rate of turn builds up relatively slowly - in fact
no faster than the time it takes your centre of mass to drop (in the case of 45 degrees) to
sqrt(2) of its straight line height. If you want to retain control of the bike, it's a lot longer
than that.

It's the initial rate of turning that's the issue, not the maximum sustainable steady state rate.

You need to learn about countersteering and forced turns.

There's a brief mention in cyclecraft, but google is probably a better bet.

clive

James Annan posted ...

Quoted message said:

Trevor Barton said:

Bikes have pointy bits.

[...]

Quoted message said:

If I had a choice between being hit by a car at 20mph or a bike at the same speed, it'd be the
car any day.

Then you are a fool. All this nonsense about 'pointy bits' ignores the fact that the vast bulk of
the energy/momentum is carried by the soft squidgy rider. The 'pointy bits' will only do any real
damage if they are pushed into you by the mass of the rider, which is just about theoretically
possible but hardly a likely scenario. An impact with a car at 20mph has a significant chance of
_killing_ you.

James

When riding a 'bent, as Guy does, it is very likely that the mass of the rider, when involved in a
collision, needs to be taken into account. Virtually all the pointy bits are very pointy and at the
very front of a 'bent ... see Guys website photo's for confirmation, at the following link.
chapmancentral.demon.co.ukBike Optima StingerOpen ↗

or tinyurl.comywcnoOpen ↗

IMHO, who really cares what speed cyclists actually travel at, so long as they accept responsibilty
for any outcome of their actions. Actually, apart from the law, I guess the same could be said for
vehicular drivers of any persuasion .. 😉

--
Paul

(8(|) Homer rocks .. 😉

In article said:

On Mon, 23 Feb 2004 14:07:09 -0000 someone who may be "Tony Raven" <[email hidden]>
wrote this:-

Quoted message said:

I think he was complaining about them doing more than 30mph actually

The bod is complaining about the speed cyclists are doing down the hill now. He also says that the
camera has not yet been activated by a cyclist. Therefore he must be complaining about them going
at 30mph, or "just creeping over" that speed.

True. I agree with your point now.

"Simon Brooke" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Think about it, if you're leaning your bike at 45 degrees through a bend you're sustaining 1g
laterally.

Try 0.7g

Quoted message said:

A bike on any reasonable surface can do this.

Extremely hairy.

Quoted message said:

The number of cars which can handle a 1g turn without spinning out is pretty limited. Maybe a
Lotus Elise, but nothing less.

what about 0.7g?

"Trevor Barton" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

W K said:

"Simon Brooke" <[email hidden]> wrote in message news:2slrg1-
[email hidden]...

Quoted message said:

Think about it, if you're leaning your bike at 45 degrees through a

bend

Quoted message said:

Quoted message said:

Quoted message said:

you're sustaining 1g laterally.

Try 0.7g

Eh? 45 degrees is 1g down, 1G laterally, 1.4(14...)g resultant.

I got the envelope out and you are correct. OTOH this means a coefficient of friction of 1. That
makes it worse than an extremely hairy angle.

Where do you get 45 degrees from?

Quoted message said:

When riding a 'bent, as Guy does, it is very likely that the mass of the rider, when involved in a
collision, needs to be taken into account. Virtually all the pointy bits are very pointy and at
the very front of a 'bent ...

Don't forget that rotating sawblade, I mean chainwheel, stuck out the front to deter those that
might be tempted to get in the way ;-)

Tony

On Tue, 24 Feb 2004 00:04:57 +0000, Trevor Barton
<[email hidden]> wrote in message
<[email hidden]>:

Quoted message said:

Quoted message said:

E=1/2mv^2.

Quoted message said:

No, that's specious. It assumes, unreasonably, that v is the initial velocity when the impact
occurs (ie noone braked)

Not as such: both vehicles have brakes. It assumes that either vehicle will have braked by the same
amount (reasonable in the case of my recumbent, which has Very Powerful Brakes). Use of the brakes
by the driver of a vehicle may also be influenced by the potential harm to that driver in the event
of a crash.

Quoted message said:

and also that all the kinetic energy of the impactor is imparted to the impactee,

Not as such: conservation of momentum applies. In the case of the car the vast disparity in mass
is such that the velocity of both impactor and impactee after collision is approximately the same
as the mass of the impactor beforehand; with a cyclist, mass being of the same order of magnitude
as the impactee, the acceleration applied to the impactee will be lower, so injuries less likely
to be serious.

Child pedestrians hospitalised due to collision with pedal cycles in 2002-2003: 105. Child
pedestrians hospitalised due to collision with cars in 2002-2003: 2,826.

Quoted message said:

and also that the damage to a pedestrian is not influenced by the pointy bits on a bike, or the
relatively "pedestrian friendlier" fronts of modern cars. Note I use the expression "pedestrian
friendlier" somewhat tounge in cheek, and in a relative, not absolute sense.

Not as such: the car has a bumper at below knee height which accelerates the upper body and
head downward towards the bonnet. The cyclist is more likely to strike a glancing blow (being
much narrower)

Quoted message said:

The last two points are important. In any collision between a car and a pedestrian, most of the
energy is retained by the car - witness that the car's velocity is little affected by an impact
with a pedestrian.

Not as such: conservation of momentum applies. As above, the pedestrian will experience much more
severe acceleration in collision with the car.

Quoted message said:

On the other hand, it only takes a tiny bit of that energy to injure or kill a pedestrian. A 1
tonne car travelling at about 50kph has a KE of about 100MJ. A 5g bullet travelling at 500m.s-1 has
about 0.6MJ, and that's certainly enough to kill you, eh?

Logical flaw. There is a substantial difference between penetrating bullets and blunt trauma.

Quoted message said:

A bike travelling at 50kph with a fat [censored] on it so it weighs 100kg has about 10MJ. You
work it out.

Not as such: a car plus driver weighs about 15 times as much as a cyclist plus bike, and is much
wider, making collision more likely.

Quoted message said:

Bikes have pointy bits. Trauma is a function of both energy and pressure. Place 20kG on top of a
flat board, lie on the floor and put the board on your chest. Mmmm, no big deal. Now place a 6"
nail pointing downwards in the middle of the board, and do the same thing. Oops, nice little hole
in your chest.

Not as such: no bike I know of has pointy nail-like bits. At worst you'll get a cut fromt he
chainring, like I got when I ws run off the road by Captain Clueless. Such cuts are rarely fatal.

Quoted message said:

E=1/2mv^2 is not an argument for exceeding the speed limit on a bike.

Not as such: It is an argument for there being no speed limit to exceed on a bike.

Quoted message said:

If I had a choice between being hit by a car at 20mph or a bike at the same speed, it'd be the
car any day.

Really? Very strange.

Quoted message said:

Well, assuming that is, I didn't have any other choice 😉 Of course, if I had the same warning of
the impact, withing bounds I'd be better off with the bike because it's narrower and I'm more
likely to be able to avoid it by jumping out of the way,

Give the man a peanut.

Quoted message said:

but that's *still* not an argument for knowingly speeding on a bike.

No argument necessary: one cannot speed on a bike. The offence does not exist.

Guy
===
May contain traces of irony. Contents liable to settle after posting.
chapmancentral.demon.co.ukchapmancentral.demon.co.ukOpen ↗

88% of helmet statistics are made up, 65% of them at Washington University

Tony Raven posted ...

Quoted message said:

Quoted message said:

When riding a 'bent, as Guy does, it is very likely that the mass of the rider, when involved in
a collision, needs to be taken into account. Virtually all the pointy bits are very pointy and at
the very front of a 'bent ...

Don't forget that rotating sawblade, I mean chainwheel, stuck out the front to deter those that
might be tempted to get in the way ;-)

Yup, and probably far less 'pedestrian friendly', if ever in a vehicle/pedestrian collision, than
the large flat bits of metal and plastic that adorn the front of my 4 x 4 ... which seems to be one
of the main arguments bandied about regarding my main mode of family transport .. 😉

--
Paul

(8(|) Homer rocks .. 😉

"Just zis Guy, you know?" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Child pedestrians hospitalised due to collision with pedal cycles in 2002-2003: 105. Child
pedestrians hospitalised due to collision with cars in 2002-2003: 2,826.

Those numbers don't look right to me. If they are right, then bikes are more dangerous than cars.

cheers, clive

Trevor Barton said:

Oh, but of course I'm a fool, perhaps because I use the word manoeuverability to describe how
quickly a car or a bike can, err, manoeuver, rather than the size of the gap it can fit through.
Or perhaps you misunderstood because I misspelled it?

The point is that the bike only has to manoeuver a few inches to avoid a direct hit or a foot for a
complete miss. That's barely a twitch of the handlebars. A car driver has to wind the steering wheel
around laboriously to manage anything more than a gentle turn, and they have to move the car several
feet laterally to avoid a direct impact.

Quoted message said:

Quoted message said:

The fixed period is very different for moving a foot from accelerator to brake, than for pulling a
brake lever which is already under the fingers.

Is it really.

You don't really doubt this do you?

James

On Tue, 24 Feb 2004 19:05:13 +0000, Trevor Barton
<[email hidden]> wrote in message
<[email hidden]>:

Quoted message said:

You're mistaking manoeuverability for something else.

I can't make my car move sideways by its entire width just by shifting my body.

Guy
===
May contain traces of irony. Contents liable to settle after posting.
chapmancentral.demon.co.ukchapmancentral.demon.co.ukOpen ↗

88% of helmet statistics are made up, 65% of them at Washington University

On Tue, 24 Feb 2004 19:57:26 -0000, "Clive George"

<[email hidden]>:

Quoted message said:

Those numbers don't look right to me. If they are right, then bikes are more dangerous than cars.

They are right, but remember that they include all children injured by all bikes everywhere, while
cars are mainly to be found on the road.

Guy
===
May contain traces of irony. Contents liable to settle after posting.
chapmancentral.demon.co.ukchapmancentral.demon.co.ukOpen ↗

88% of helmet statistics are made up, 65% of them at Washington University

"Trevor Barton" <[email hidden]> wrote

Quoted message said:

DavidR said:

"Trevor Barton" <[email hidden]> wrote

Quoted message said:

Quoted message said:

Quoted message said:

If I had a choice between being hit by a car at 20mph or a bike at the same speed, it'd be the
car any day. Well, assuming that is, I didn't have any other choice 😉

Even a direct hit is below the waist. Above the waist the rider must be softer than a
windscreen.

Quoted message said:

Of course, if I had the same warning of the impact, withing bounds I'd be better off with
the bike because it's narrower and I'm more likely to be able to avoid it by jumping out of
the way,

...and the rider has more sideways room...

... And a hellofa lot less manoeverability ...

Come again?

Quoted message said:

Quoted message said:

...and the rider has more incentive not to hit you.

You would do less to avoid hitting a pedestrian when in a car than when on a bike??

Who can tell? Although I have had a few "near pedestrian events" on the bike, I cannot recall of any
within the last 25 years whilst driving.

A recent experience was that I was approaching two student age women waiting on the edge of the
pavement. I moved to right of centre lane and mentally prepared myself. They stepped off, I went
for the brakes. One stopped while the other continued so I steered between them (that space &
maneouvreability thing) . There was no possibility of stopping in time and certainly no space to
fit a car.

Quoted message said:

Quoted message said:

Below 20mph I can outbrake any car. 30mph plus is admittedly less easy (though at that speed I
am unable to make a comparison using a flat road).

I'm not sure you can.

Oh I can.

Quoted message said:

Below 20mph braking times are quick either way (to a halt) Reaction times are liable to be very
very significant as they are a fixed period irrespective of speed, ie at 70mph the reaction time
is only a small proportion of the total *time* to a halt, whereas at 20mph they are far more
significant. At 70 they make a far more significant difference to the *distance* required to stop.

Reaction time includes thought, hand or foot movement and vehicle brake lag. The latter two are
much, much faster on a bike. The bike can shed a couple mph before the car has even started..