Legal at night?

DIscuss anything relating to non-standard cycles and their equipment.
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Wildduck
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Postby Wildduck » 3 Jul 2008, 11:29am

I'll elaborate on the asbos....

Number one: Approaching mini-roundabout at speed. Learner driver on other side. Sharp right turn attempted. Inside wheel lifted quite sharply, just about balancing on the correct side of tipping. Learner driver appeared a little grey. My life flashed before me. First asbo well deserved.

Number two: Out on a club run. Going downhill on a narrow, gravel strewn road which was damp and just a little 'greasy'. Back wheel starts snaking left and right as I wrestle and struggle to stop Quackers dumping me in a ditch.

Since then Quackers has lifted a inside wheel slightly a couple of times at worst but I just put that down to a little bit of 'rough play'. But Mrs.Wildduck is right, the next time he pushes his luck a little too far its a third asbo, a tag and a cufew!
Trice Q 2007 in inky blue (Quackers)
Bacchetta Corsa 26 ATT (The Mad Weeble)
Cube SL Team Cross (Rubberduckzilla)
Homebaked tourer (The Duck's Dream)
MTB mongrel (Harold the Flying Sheep)

Khornight
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Postby Khornight » 3 Jul 2008, 7:28pm

drossall wrote:
Yorkshireman wrote:The rear tyre was also examined and the officer pointed out that whilst bald in many areas along the centre of the tread that would not have caused any problems in the dry conditions.


Then it wouldn't cause problems in wet conditions either. It's a bike tyre, not a car one. Bikes aquaplane at 120mph+.

A bald tyre might puncture or blow out, but whether the roads are dry isn't so relevant to that.


2 questions, where is the aquaplane factiod from and is aquaplaning more likely to cause a crash than skidding generally? Or is a bald tire not more likely to have a skid?

Does that mean that in wet conditions until a bike is travelling at 120mph, it's just as controllable as in dry conditions?

(by the way, I hope the questions don't come off too confrontational, I'm just asking...)

drossall
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Postby drossall » 3 Jul 2008, 10:56pm

No, no problem, ask away. A bald (= rubber but no tread pattern) tyre on a bicycle is, if anything, less likely to skid in the wet than a treaded tyre. For this reason some professionals prefer slicks in the wet - the opposite of what you would do in a car. This doesn't mean that braking is as good as in the dry, no.

I don't know whether anyone has tested a tyre worn to the canvas against one with rubber. I'd back the one with rubber, wet or dry, but that's instinct not fact.

There's a good answer to your question about control in Wikipedia - choose the one on tyres. You'd also need to consider the mixture of vehicle oil and water that can make roads slippery in wet conditions. Sheldon Brown, as ever, has the authoritative statement. In summary, though, saying that slicks are better in the wet than treads does not mean that either is as good as a tyre would be in the dry.

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CJ
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Re: Legal at night?

Postby CJ » 10 Jul 2008, 1:12pm

byegad wrote:... should we ask CTC to lobby for the necessary changes at the next opportunity?

No need. I already have done, at every opportunity throughout the past 24 years!

What's lacking is a parallel campaign by the cycle trade and industry - and for all those racing cyclists to get their heads out of the sand too! What I get every time is "nobody else except CTC thinks its a problem" so the law stays the same!
Chris Juden
One lady owner, never raced or jumped.

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Deckie
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Postby Deckie » 11 Jul 2008, 5:10pm

Khornight wrote:
drossall wrote:
Yorkshireman wrote:The rear tyre was also examined and the officer pointed out that whilst bald in many areas along the centre of the tread that would not have caused any problems in the dry conditions.


Then it wouldn't cause problems in wet conditions either. It's a bike tyre, not a car one. Bikes aquaplane at 120mph+.

A bald tyre might puncture or blow out, but whether the roads are dry isn't so relevant to that.


2 questions, where is the aquaplane factiod from and is aquaplaning more likely to cause a crash than skidding generally? Or is a bald tire not more likely to have a skid?

Does that mean that in wet conditions until a bike is travelling at 120mph, it's just as controllable as in dry conditions?

(by the way, I hope the questions don't come off too confrontational, I'm just asking...)


The figure is probably a bit on the high side, but the theory comes from the aviation industry. They have spent many years working out landing speeds to avoid aircraft aquaplaning off runways and have discovered a neat equasion that seems to work at all the speeds they have tried.

The equasion is: the speed above which aquaplaning is likely is 9 times the square root of the tyre pressure (in PSI).

Thus for a bike with a tyre inflated to 100PSI would have a theoretical aquaplaning speed of 9x10, or 90mph.

As bike tyres are so narrow (in comparison to other road users) the tyre is far more likely to cut through standing water to the road surface. There is still the problem of stopping on a greasy surface though...

byegad
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Postby byegad » 12 Jul 2008, 5:51pm

Thanks for your comments CJ. So where do we go then? It's only a matter of time before some smart motorist defence lawyer waves no reflectored pedals in court.

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Wildduck
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Postby Wildduck » 13 Jul 2008, 3:21pm

Ditto. Big worry for me also.
Trice Q 2007 in inky blue (Quackers)
Bacchetta Corsa 26 ATT (The Mad Weeble)
Cube SL Team Cross (Rubberduckzilla)
Homebaked tourer (The Duck's Dream)
MTB mongrel (Harold the Flying Sheep)

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Cunobelin
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Postby Cunobelin » 13 Jul 2008, 9:08pm

Wildduck wrote:Ditto. Big worry for me also.



I have a front light at some 20 times the required 2.4 watt output, backed up by a flashing light at some 6 times the required output.

My rear light is at 10 times the required output.


Are you really saying that your client missed these, but would have seen a pair of reflectors?

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Wildduck
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Postby Wildduck » 14 Jul 2008, 7:00am

I don't think there's one person on here that would disagree with you but when did the obvious and common sense have anything to do with the law?
Trice Q 2007 in inky blue (Quackers)
Bacchetta Corsa 26 ATT (The Mad Weeble)
Cube SL Team Cross (Rubberduckzilla)
Homebaked tourer (The Duck's Dream)
MTB mongrel (Harold the Flying Sheep)

byegad
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Postby byegad » 14 Jul 2008, 11:12am

Wildduck has it right, Common sense and the law can be mutually exclusive.

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CJ
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Postby CJ » 15 Jul 2008, 1:21pm

byegad wrote:Thanks for your comments CJ. So where do we go then? It's only a matter of time before some smart motorist defence lawyer waves no reflectored pedals in court.

The lack of pedal reflectors was mentioned in court, and in the papers, as one of the several negligencies of that cyclist who was all over the news recently for causing the death of a pedestrian. This is despite the fact that (unless the pedestrian was wearing a headtorch) they would have made absolutely no difference whatsoever. Hand them a stick and you can be sure they will beat us with it.

I think one place we go from here is a bigger forum! One snag with having so many special-interest message boards is your message doesn't reach much of an audience. It was a bit of a fluke I saw it in the first place!
Chris Juden
One lady owner, never raced or jumped.

byegad
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Postby byegad » 15 Jul 2008, 2:05pm

Hi CJ, I've started a thread in On the Road.

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Wildduck
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Postby Wildduck » 15 Jul 2008, 3:06pm

Visited, put a comment and now chewing on a solution...
Trice Q 2007 in inky blue (Quackers)
Bacchetta Corsa 26 ATT (The Mad Weeble)
Cube SL Team Cross (Rubberduckzilla)
Homebaked tourer (The Duck's Dream)
MTB mongrel (Harold the Flying Sheep)

CW
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Postby CW » 17 Jul 2008, 9:00pm

Instead of typing it out all again see my post http://forum.ctc.org.uk/viewtopic.php?t=14812&start=15

My poor fingers are now aching. Two to be exact
Chris

byegad
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Postby byegad » 17 Jul 2008, 10:02pm

Thanks CW, it looks like we'd be pushing on an open door if only we time our lobbying to coincide with a new bill.