Cyclist likely to be convicted of manslaughter..

[b2hbm]

XCP said:

There must be a reason they choose to ride them though. People who make a living getting from A to B quickly must see some advantage. I just wondered what that is.

amongst a lot of folks these days, I'm convinced it's just a fashion statement amongst a lot of the riders.

As some have mentioned, having only a single gear means that there is very little maintenance on the bike and once set up they go on for ages without adjustment. The bikes are also very much lighter and because the gear is usually low (ish) they feel to have a faster response off the mark. Good for the traffic light grand prix

Many years ago a fixed wheel was the done thing for club riders on winter club runs because gears were expensive and you'd save your good stuff for summer. I used to set up a fixed bike in November and ride it until spring, as did many others but if we used a road frame we'd keep both brakes and I never saw anyone riding without a front brake, even a track frame would have the fork crown drilled to accept a front brake.

Back to "why ?", well there's an added bonus from the fact that you can't freewheel; you either develop a very smooth and supple pedal action or you fall off.

Having only a single gear also means that you generally end up pedalling faster (higher cadence) which again helps you to gain fitness and control your breathing. Even on 10/12 speed racing bikes back then the gears tended to be much lower than is common these days and pedalling fast was generally the way everyone raced, so the training for higher cadences wins again.

So that's basically why a serious cyclist would ride fixed wheel; it's just one of those things that you either get or you don't. As to why a courier would want to ride one I don't understand, I would have thought a single speed freewheel made more sense in traffic and would let you corner faster.

[The Surveyor]

Has there been a verdict on this case, I can't find any update?

[KTF]

The Surveyor said:

Has there been a verdict on this case, I can't find any update?

I think the jury retired to think about it yesterday.

[fido]

turbobloke said:

Less KE in the bike and the biker before impact, but as both bike and biker were still moving after the impact, KE transfer would be 'very partial'. KE is most interesting in a head-on which brings e.g. two vehicles to a halt without deformation where people are unrestrained inside (i.e. unrealistic). Change of momentum is worth looking at with collisions involving moving objects including people that deform and move on after colliding: Ft (impulse) = mv-mu.

Thanks for the physics lesson TB. Bearing that in mind, the coefficient of restitution between the outside of a helmet and a human skull must be quite high, if they happen to collide at that height.

Here's another pedestrian-cyclist accident:-

http://www.cyclingweekly.com/news/latest-news/new-...

Edited by fido on Tuesday 22 August 13:30

[turbobloke]

That may be sarcasm regarding a physics lesson but KE still isn't the most helpful perspective on this type of situation, even less so with cars rather than cycles, but the presence of a v-squared term is attractive and abused by some to bring undue focus on speed in low speed collisions.

[fido]

turbobloke said:

That may be sarcasm regarding a physics lesson

No it was a genuine compliment. I agree that the damage on impact will depend on the change in momentum, but with the amount of k.e. being the upper limit depending on the nature of the collision (no?)

[mac96]

fido said:

turbobloke said:

Less KE in the bike and the biker before impact, but as both bike and biker were still moving after the impact, KE transfer would be 'very partial'. KE is most interesting in a head-on which brings e.g. two vehicles to a halt without deformation where people are unrestrained inside (i.e. unrealistic). Change of momentum is worth looking at with collisions involving moving objects including people that deform and move on after colliding: Ft (impulse) = mv-mu.

That's for the physics lesson TB. Bearing that in mind, the coefficient of restitution between the outside of a helmet and a human skull must be quite high, if they happen to collide at that height.

Here's another pedestrian-cyclist accident:-

http://www.cyclingweekly.com/news/latest-news/new-...

Interesting combination of circumstances and lessons there:
Pedestrian not looking properly
Dash cammer possibly flashed pedestrian to cross( although glint on back of bus could be something else).
Cyclist looks to be too fast given busy wet road and also should have noticed ped sooner.

Everyone at fault.

[Sylvaforever]

mac96 said:

Interesting combination of circumstances and lessons there:
Pedestrian not looking properly
Dash cammer possibly flashed pedestrian to cross( although glint on back of bus could be something else).
Cyclist looks to be too fast given busy wet road and also should have noticed ped sooner.

Everyone at fault.

Nope.

[mac96]

Sylvaforever said:

mac96 said:

Interesting combination of circumstances and lessons there:
Pedestrian not looking properly
Dash cammer possibly flashed pedestrian to cross( although glint on back of bus could be something else).
Cyclist looks to be too fast given busy wet road and also should have noticed ped sooner.

Everyone at fault.

Nope.

Thanks for the complete rebuttal!

[turbobloke]

fido said:

turbobloke said:

That may be sarcasm regarding a physics lesson

No it was a genuine compliment. I agree that the damage on impact will depend on the change in momentum, but with the amount of k.e. being the upper limit depending on the nature of the collision (no?)

Sort of, KE as an upper limit leads to bizarre (and unreal!) scenarios where a pedestrain moves away from the scene of an impact at ridiculous speed which just don't occur...a 2000kg BMW 7-series travelling at the lowly speed of 10 metres per second hitting a 100kg pedestrian and transferring all its KE would cause the pedestrian to travel away from the scene of the accident at 100mph near as dammit (no deformation).

I've had the misfortune to witness several low speed impacts like that and the pedestrian ends up in the air (mgh) and lands not too far away from the car. At low speeds, the outcome for pedestrians is down to luck, i.e. does their head hit the bonnet at a location with no struts underneath or does it hit the A-pillar. With a cyclist, something soft may hit the pedestrian rather than the cycle frame or a helmet with a head in it.

With luck you'll understand the intial thoughts over possible sarcasm, this being PH.

[oyster]

SantaBarbara said:

There should be a registration system for Cyclists, and they should have a number visible on their vests

That seems to prevent car drivers killing anyone.

[johnfm]

Jail time probably the right result here.

He showed no remorse at all, took no responsibility for his actions, was riding an illegal (for road use bike) and killed someone.

2 years (out in one) would focus his mind a bit.

[turbobloke]

oyster said:

SantaBarbara said:

There should be a registration system for Cyclists, and they should have a number visible on their vests

That seems to prevent car drivers killing anyone.

The actual point being that if they do commit an offence, serious (fatac) or less so, they are more easily identifiable.

[Ali G]

Elastic and inelastic collisions

http://physics.tutorvista.com/momentum/elastic-col...

[turbobloke]

[eccles]

fido said:

Thanks for the physics lesson TB. Bearing that in mind, the coefficient of restitution between the outside of a helmet and a human skull must be quite high, if they happen to collide at that height.

Here's another pedestrian-cyclist accident:-

http://www.cyclingweekly.com/news/latest-news/new-...

Edited by fido on Tuesday 22 August 13:30

I love the way that cyclist shows a caring side by checking his bike over and mounting up, preparing to cycle away, all whilst the person he hit is crouched down, clearly injured/distressed on the pavement!

[heebeegeetee]

eccles said:

I love the way that cyclist shows a caring side by checking his bike over and mounting up, preparing to cycle away, all whilst the person he hit is crouched down, clearly injured/distressed on the pavement!

"but the filming car moves off before the cyclist so the end of the episode is unknown."
Read more at http://www.cyclingweekly.com/news/latest-news/new-...

Hey but let's not tribalism get in the way of anything.

[turbobloke]

heebeegeetee said:

eccles said:

I love the way that cyclist shows a caring side by checking his bike over and mounting up, preparing to cycle away, all whilst the person he hit is crouched down, clearly injured/distressed on the pavement!

"but the filming car moves off before the cyclist so the end of the episode is unknown."
Read more at http://www.cyclingweekly.com/news/latest-news/new-...

Hey but let's not tribalism get in the way of anything.

Nah it's too late, first concerns should have been with the person who got hit, not machinery.

[eccles]

heebeegeetee said:

eccles said:

I love the way that cyclist shows a caring side by checking his bike over and mounting up, preparing to cycle away, all whilst the person he hit is crouched down, clearly injured/distressed on the pavement!

"but the filming car moves off before the cyclist so the end of the episode is unknown."
Read more at http://www.cyclingweekly.com/news/latest-news/new-...

Hey but let's not tribalism get in the way of anything.

I love the way they intimate the pedestrian is playing for sympathy....
"Before crouching down it had looked like the pedestrian was ready to leave the scene." Like they can tell that from that footage!

[Twilkes]

fido said:

Here's another pedestrian-cyclist accident:-

http://www.cyclingweekly.com/news/latest-news/new-...

The cyclist initially looked to be heading down the leg side, so the pedestrian thought he had a free shot and went for it - but the cyclist pitched on leg stump, cut back to hit middle and struck the pedestrian dead in front of the wicket. Plumb and out.

But the cyclist should never have been bowling that fast in those conditions, especially as it looked like an amateur game (no whites) so skipper should withdraw him from the attack. Poor show old chap.