Cheapo bike



H

half_pint

Guest
"Simon Brooke" <[email protected]> wrote in message
news:p[email protected]
> in message <[email protected]>, half_pint
> ('[email protected]') wrote:
>
> > "Jon Senior" <jon_AT_restlesslemon_DOTco_DOT_uk> wrote in message
> > news:[email protected]
> >> half_pint [email protected] opined the following...
> >> > Weight makes you take a little longer to reach a given speed, but
> >> > once you attain that speed it is easier to maintain as you have
> >> > more momentum (kinetic energy).
> >>
> >> Except in situations of obvious continuous acceleration such as hill-
> >> climbing, where having a lighter bike is noticeable. I bought a new
> >> road bike just over a year ago which was pretty similar in spec to
> >> the old one I replaced (Both Shimano 105 equipped), but had an
> >> aluminium frame and more modern components.

> >
> > Granted you will go up faster than me but I will be faster going
> > down!!

>
> I'd like to see you try it. What's your current record downhill speed,
> Jon?



When thrown over a clift my bike will reach the bottom first.

>
> --
> [email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/
>
> :: Wisdom is better than weapons of war ::
> :: Ecclesiastes 9:18 ::
 
J

Just zis Guy, you know?

Guest
On Tue, 30 Nov 2004 20:15:55 -0000, "half_pint"
<[email protected]> wrote:

>When thrown over a clift my bike will reach the bottom first.


Thus proving that aerodynamics are more important than mass when
riding downhill.

Best clear your weapon now before you take out the other foot.

Guy
--
May contain traces of irony. Contents liable to settle after posting.
http://www.chapmancentral.co.uk

88% of helmet statistics are made up, 65% of them at CHS, Puget Sound
 
I

iarocu

Guest
Steve L <[email protected]> wrote in message news:<[email protected]>...
> Say you only had around £150 to spend, which bike would you choose?


I would wait until I could spend more. This months CTC magazine has a
review of cheap bikes. Defined as less than £300. The reviewer stated
that even at that price there was a lot of rubbish on the market.
One recommended buy was Edinburgh Bicycle Cooperatives Courier. A
MTB frame with a single front chainring, 8 speed back cogs and city
tyres. Simple and effective. £240. I've left the magazine at work so
can't quote the other models recommended.
Iain
 
H

half_pint

Guest
"Just zis Guy, you know?" <[email protected]> wrote in message
news:[email protected]
> On Tue, 30 Nov 2004 20:15:55 -0000, "half_pint"
> <[email protected]> wrote:
>
> >When thrown over a clift my bike will reach the bottom first.

>
> Thus proving that aerodynamics are more important than mass when
> riding downhill.


Wellgiven that the bikes have basically the same aerodynamic your comments
are ignorant, please think a little harder before post

>
> Best clear your weapon now before you take out the other foot.
>
> Guy
> --
> May contain traces of irony. Contents liable to settle after posting.
> http://www.chapmancentral.co.uk
>
> 88% of helmet statistics are made up, 65% of them at CHS, Puget Sound
 
H

half_pint

Guest
"iarocu" <[email protected]> wrote in message
news:[email protected]
> Steve L <[email protected]> wrote in message

news:<[email protected]>...
> > Say you only had around £150 to spend, which bike would you choose?

>
> I would wait until I could spend more. This months CTC magazine has a
> review of cheap bikes. Defined as less than £300. The reviewer stated
> that even at that price there was a lot of rubbish on the market.
> One recommended buy was Edinburgh Bicycle Cooperatives Courier. A
> MTB frame with a single front chainring, 8 speed back cogs and city
> tyres. Simple and effective. £240. I've left the magazine at work so
> can't quote the other models recommended.


Yes but the post says £150, can you not answer the question with out
changing it?

Teacher: "What is the capital of France?"
Pupil: "The capital of Spain is Madrid"

In my days answers like that would have resulted in a slap in the face
and 1000 lines.

> Iain
 
D

Doki

Guest
half_pint wrote:

>
> When thrown over a clift my bike will reach the bottom first.


You never did Physics did you?
 
H

half_pint

Guest
"Doki" <[email protected]> wrote in message
news:[email protected]
>
>
> half_pint wrote:
>
> >
> > When thrown over a clift my bike will reach the bottom first.

>
> You never did Physics did you?


Only as far as 'A' level, the finer points are not covered
at CSE level, as you have demonstrated.

>
>
 
Z

Zardoz

Guest

>> half_pint wrote: <more badly thought out shite>
>>
>> >
>> > When thrown over a clift my bike will reach the bottom first.



OK basic 'O' level kinematics equation

v = u + a * t

v = final speed
u = initial speed
t = time
a = acceleration

integrate with respect to t to get

s = u * t + 1/2 a * t^2


s = distance



plug in values for the height of the cliff (s) initial speed (u=0),
acceleration (= gravity) and t will tell you how long it takes to
reach the bottom. But hang on... there's no factor for WEIGHT because
WEIGHT IS IRRELEVENT. All bikes fall at the same speed...


In the real world acceleration is factored by wind resistance R
a = g-r


So the only thing affecting the downwards speed of a bike is rolling
and wind resistance.

There's an astronaut on the moon dropping an anvil and a feather ...
which one hits the ground first??

This is always true under Newtonian laws of motion. If you start
traveling near the speed of light the rules change a bit.
 
T

Tim Hall

Guest
On Tue, 30 Nov 2004 21:21:03 -0000, "half_pint"
<[email protected]> wrote:

>
>"Just zis Guy, you know?" <[email protected]> wrote in message
>news:[email protected]
>> On Tue, 30 Nov 2004 20:15:55 -0000, "half_pint"
>> <[email protected]> wrote:
>>
>> >When thrown over a clift my bike will reach the bottom first.

>>
>> Thus proving that aerodynamics are more important than mass when
>> riding downhill.

>
>Wellgiven that the bikes have basically the same aerodynamic your comments
>are ignorant, please think a little harder before post



Oh dearie dearie me.

You haven't seen Guy's bike haven't you?

Tim
 
D

Doki

Guest
half_pint wrote:
> "Doki" <[email protected]> wrote in message
> news:[email protected]
>>
>>
>> half_pint wrote:
>>
>>>
>>> When thrown over a clift my bike will reach the bottom first.

>>
>> You never did Physics did you?

>
> Only as far as 'A' level, the finer points are not covered
> at CSE level, as you have demonstrated.


I'm pretty sure you've got no idea whether your bikes more aerodynamic than
anyone elses's when it's tumbling down the side of a cliff. Ignoring aero
drag, two objects of differing mass will drop at the same speed.
 
H

half_pint

Guest
"Tim Hall" <[email protected]> wrote in message
news:[email protected]
> On Tue, 30 Nov 2004 21:21:03 -0000, "half_pint"
> <[email protected]> wrote:
>
> >
> >"Just zis Guy, you know?" <[email protected]> wrote in message
> >news:[email protected]
> >> On Tue, 30 Nov 2004 20:15:55 -0000, "half_pint"
> >> <[email protected]> wrote:
> >>
> >> >When thrown over a clift my bike will reach the bottom first.
> >>
> >> Thus proving that aerodynamics are more important than mass when
> >> riding downhill.

> >
> >Wellgiven that the bikes have basically the same aerodynamic your

comments
> >are ignorant, please think a little harder before post

>
>
> Oh dearie dearie me.
>
> You haven't seen Guy's bike haven't you?


He hasn't seen mine either.

>
> Tim
 
H

half_pint

Guest
"Zardoz" <[email protected]> wrote in message
news:[email protected]
>
> >> half_pint wrote: <more badly thought out shite>
> >>
> >> >
> >> > When thrown over a clift my bike will reach the bottom first.

>
>
> OK basic 'O' level kinematics equation
>
> v = u + a * t
>
> v = final speed
> u = initial speed
> t = time
> a = acceleration
>
> integrate with respect to t to get
>
> s = u * t + 1/2 a * t^2
>
>
> s = distance
>
>
>
> plug in values for the height of the cliff (s) initial speed (u=0),
> acceleration (= gravity) and t will tell you how long it takes to
> reach the bottom. But hang on... there's no factor for WEIGHT because
> WEIGHT IS IRRELEVENT. All bikes fall at the same speed...
>
>
> In the real world acceleration is factored by wind resistance R
> a = g-r
>
>
> So the only thing affecting the downwards speed of a bike is rolling
> and wind resistance.
>
> There's an astronaut on the moon dropping an anvil and a feather ...
> which one hits the ground first??
>
> This is always true under Newtonian laws of motion. If you start
> traveling near the speed of light the rules change a bit.


Oh dear....

Drop a feather amd drop a brick (preferably on you foot) and see
which falls faster.

A falling (or rolling down hill) object reaches its terminal velocity
(maximum speed) when the air resistance matches the downward force.

http://www.grc.nasa.gov/WWW/K-12/airplane/termv.html

Terminal velocity (V).
--------------------------------------------------------

We can determine the value of the terminal velocity by doing a little
algebra and using the drag equation. Drag depends on a drag coefficient, Cd
the air density, r the square of the velocity V and some reference area A of
the object:

D = Cd * r * V ^2 * A / 2

At terminal velocity, D = W. Solving for the velocity, we obtain the
equation

V = sqrt ( (2 * W) / (Cd * r * A) )
---------------------------------------------------

Thus terminal velocity is proportional to the square root of weight, if you
dispute
then have a word with Nasa.

I am sure they will take your views in account (ie dismiss them) when
designing
the next generation of space shuttles :O|

>
>
>
>
>
>
 
H

half_pint

Guest
"Doki" <[email protected]> wrote in message
news:[email protected]
>
>
> half_pint wrote:
> > "Doki" <[email protected]> wrote in message
> > news:[email protected]
> >>
> >>
> >> half_pint wrote:
> >>
> >>>
> >>> When thrown over a clift my bike will reach the bottom first.
> >>
> >> You never did Physics did you?

> >
> > Only as far as 'A' level, the finer points are not covered
> > at CSE level, as you have demonstrated.

>
> I'm pretty sure you've got no idea whether your bikes more aerodynamic

than
> anyone elses's when it's tumbling down the side of a cliff. Ignoring aero
> drag, two objects of differing mass will drop at the same speed.


However you cannot ignore aero drag, you certaintly won't win any bicycle
races if you do.

>
>
 
H

Hywel Jenkins

Guest
In article <[email protected]>, [email protected]
says...
>
> "iarocu" <[email protected]> wrote in message
> news:[email protected]
> > Steve L <[email protected]> wrote in message

> news:<[email protected]>...
> > > Say you only had around £150 to spend, which bike would you choose?

> >
> > I would wait until I could spend more. This months CTC magazine has a
> > review of cheap bikes. Defined as less than £300. The reviewer stated
> > that even at that price there was a lot of rubbish on the market.
> > One recommended buy was Edinburgh Bicycle Cooperatives Courier. A
> > MTB frame with a single front chainring, 8 speed back cogs and city
> > tyres. Simple and effective. £240. I've left the magazine at work so
> > can't quote the other models recommended.

>
> Yes but the post says £150, can you not answer the question with out
> changing it?
>
> Teacher: "What is the capital of France?"
> Pupil: "The capital of Spain is Madrid"
>
> In my days answers like that would have resulted in a slap in the face
> and 1000 lines.


Looks like you were slapped one too many times - you're brain's fscked.

half-wit, your entire contribution to this thread is full of ****. Why
don't you just sit back and STFU and listen to the people that know so
much more than you? You really are a *****. I just know that you're
sitting there, in your soiled underwear with a smug "I know better" grin
on your fat, stubbly, dribbling face, when deep down you know you're an
idiot. Go on, push off back to uk.legal with your standard ratio TV.

--
Hywel
 
J

Jon Senior

Guest
half_pint [email protected] opined the following...
> Granted you will go up faster than me but I will be faster going down!!


Really? My current record stands at 48mph, and I intend to better that
soon. Given that the enormous amount of cod knowledge that you carry
with you will inevitably slow you down, I'll beat you up and down the
hill.

> Yes generally but if you do not eat a healthy ammount you will not feel
> very energetic at all!


But that does not change the maths. I believe that what you are saying
is, "If you eat less, you may feel less inclined to exercise and thus
will use even less energy.". This however has no effect on the in:eek:ut
ratio for energy. It's an argument for eating a sensible diet.

> Well yes it is a bit of an 'old wives tale' but there tends to be quite a
> lot
> of truth in them, if you eat in the morning you may well feel more energetic
> and burn that energy off, you will not burn much energy off when you are
> asleep!


A "bit of an 'old wive's tale'"? Presumably, one should only eat in the
morning then. Your whole metabolism slows down while you sleep. This
means you use less energy than when walking around during the day, but
also means that you put down fat more slowly.

Once more, regardless of when you eat, if you take in more energy than
you use, you will gain weight.

Jon
 
Z

Zardoz

Guest

>Thus terminal velocity is proportional to the square root of weight, if you
>dispute
> then have a word with Nasa.
>
>I am sure they will take your views in account (ie dismiss them) when
>designing
>the next generation of space shuttles :O|


£99 space shuttle? never did me any harm. Worked for years without
maintenance :)

Do tell when your bike reaches terminal velocity and I'll come and
watch.
 
J

Jon Senior

Guest
half_pint [email protected] opined the following...
> Thus terminal velocity is proportional to the square root of weight, if you
> dispute
> then have a word with Nasa.
>
> I am sure they will take your views in account (ie dismiss them) when
> designing
> the next generation of space shuttles :O|


I strongly suspect that anyone at Nasa talking about "weight" will find
themselves travelling well in excess of terminal velocity on their way
to the job centre!

Jon
 
C

Carol Hague

Guest
half_pint <[email protected]> wrote:


>
> When thrown over a clift my bike will reach the bottom first.


Ahem. There's some chap outside called Galileo who'd like a word about
that...

--
Carol
"I was just being a little teapot. It's a bad habit of mine"
- Wyvern, Randall & Hopkirk (Deceased).
 
J

Julesh

Guest
Carol Hague wrote:

> half_pint <[email protected]> wrote:
>
>
>
>>When thrown over a clift my bike will reach the bottom first.

>
>
> Ahem. There's some chap outside called Galileo who'd like a word about
> that...
>

And it's likely to need servicing afterwards.


julesh
 
J

Just zis Guy, you know?

Guest
On Tue, 30 Nov 2004 21:21:03 -0000, "half_pint"
<[email protected]> wrote:

>> >When thrown over a clift my bike will reach the bottom first.


>> Thus proving that aerodynamics are more important than mass when
>> riding downhill.


>Wellgiven that the bikes have basically the same aerodynamic your comments
>are ignorant, please think a little harder before post


I thought you were suggesting we should throw both you and your bike
off the cliff to see which one hit first. Or if anyone cared.

As to "drop both bikes off the cliff" - never heard of Galileo have
you?

Guy
--
May contain traces of irony. Contents liable to settle after posting.
http://www.chapmancentral.co.uk

88% of helmet statistics are made up, 65% of them at CHS, Puget Sound