R
Roger Merriman
Guest
David Damerell <[email protected]> wrote:
> Quoting Roger Merriman <[email protected]>:
> >David Damerell <[email protected]> wrote:
> >>Quoting Roger Merriman <[email protected]>:
> >>>David Damerell <[email protected]> wrote:
> >>>>But your perceptions of brake "power" are worthless because every decent
> >>>>design of brake has exactly the same stopping power on a solo.
> >>>maybe in paper,
> >>And in elementary mechanics.
> >i'm sure it terms of heat they are much of a muchness. and yes if you
> >don't move at point X the bike will endo.
>
> And for a given bottom position, every design of brake has the same
> stopping power.
yes but you'll have a job realising that. you will not beable to pull
the levers hard enought.
you can get to the point that the bike will not endo how ever hard you
pull the brakes.
>
> >>>but taking my old cant bike away from the rolling downs
> >>>and to the beacons shows that while it's brakes can cope with the soft
> >>>lumps of the south east. proper hills it lacks the power, compared with
> >>>a newer bike with disks.
> >>Which is still rubbish because an increasing downhill gradient _reduces_
> >>the maximum deceleration.
> >yes if i sit on the saddle and just jank the brake, but most will learn
> >to get out of the saddle and use that weight.
>
> Doesn't matter. If you can brake on the those soft lumps, you can manage
> the deceleration possible on proper hills because it _is less_.
>
no it's perfectly possible to counter. it isn't hard at all.
> >>Which is also still rubbish as anyone can determine with heavy panniers.
> >>30kg in panniers shifts the centre of gravity more than you can by moving
> >>your bottom; and with 30kg in panniers you can still lift the rear wheel
> >>under braking; and a downhill gradient still reduces the maximum
> >>deceleration before that happens.
> >yes of coarse a hill will increase a heavly laden bikes endo point, but
> >you weigh a lot more than 30KG and on some bikes you can move that
> >weight around a lot,
>
> You can move _some_ of that weight around a lot; your arms and legs don't
> move so much for a given bottom shift. And when we say "a lot", it's not a
> lot compared to the distance that rear panniers are below and to the rear
> of the saddle.
>
on a bike with out rider yes, but a heavily panniered bike will have a
rider when moving, and is likely to be a lot heaver, higher and more
forward, reduceing the benfit of the paniers. with regard to endos
> >>You're just clinging to purely psychosomatic ideas of brake power. It
> >>won't wash; and particularly it won't wash with anyone familiar with
> >>tandem applications, where you actually _can_ produce differences in brake
> >>power.
> >try taking a bike up and down steep hills good 30%
>
> When the gradient gets steep enough, the available braking before endo is
> small regardless of bottom position. That's one reason it's so blindingly
> obvious you're taking rubbish; you're picking the worse case for a brake
> to demonstrate supposedly superior power.
i'm not i'm pointing out that it is possible to counter the endo and
that riding up and down steep hills doesn't not mean that you end up
endoing every time you have to do a emergecy brake.
>
> >shift your weight around by that i don't mean your bottom as you put it
>
> Yes, you do. Your hands won't move; your shoulders won't get any further
> from the handlebars than they are with straight arms, although they will
> drop a bit. Your feet aren't going anywhere. The bottom is exactly the
> part that moves a lot.
on a mountain bike your shoulder will be above and just behind the
handle bars, you can move your shoulder to just above the saddle very
few hills if any would need such a move. your hands and feet stay put
but you can mover your trunk in a ark down and behind. which puts a lot
of weight lower down and rear.
roger
--
www.rogermerriman.com
> Quoting Roger Merriman <[email protected]>:
> >David Damerell <[email protected]> wrote:
> >>Quoting Roger Merriman <[email protected]>:
> >>>David Damerell <[email protected]> wrote:
> >>>>But your perceptions of brake "power" are worthless because every decent
> >>>>design of brake has exactly the same stopping power on a solo.
> >>>maybe in paper,
> >>And in elementary mechanics.
> >i'm sure it terms of heat they are much of a muchness. and yes if you
> >don't move at point X the bike will endo.
>
> And for a given bottom position, every design of brake has the same
> stopping power.
yes but you'll have a job realising that. you will not beable to pull
the levers hard enought.
you can get to the point that the bike will not endo how ever hard you
pull the brakes.
>
> >>>but taking my old cant bike away from the rolling downs
> >>>and to the beacons shows that while it's brakes can cope with the soft
> >>>lumps of the south east. proper hills it lacks the power, compared with
> >>>a newer bike with disks.
> >>Which is still rubbish because an increasing downhill gradient _reduces_
> >>the maximum deceleration.
> >yes if i sit on the saddle and just jank the brake, but most will learn
> >to get out of the saddle and use that weight.
>
> Doesn't matter. If you can brake on the those soft lumps, you can manage
> the deceleration possible on proper hills because it _is less_.
>
no it's perfectly possible to counter. it isn't hard at all.
> >>Which is also still rubbish as anyone can determine with heavy panniers.
> >>30kg in panniers shifts the centre of gravity more than you can by moving
> >>your bottom; and with 30kg in panniers you can still lift the rear wheel
> >>under braking; and a downhill gradient still reduces the maximum
> >>deceleration before that happens.
> >yes of coarse a hill will increase a heavly laden bikes endo point, but
> >you weigh a lot more than 30KG and on some bikes you can move that
> >weight around a lot,
>
> You can move _some_ of that weight around a lot; your arms and legs don't
> move so much for a given bottom shift. And when we say "a lot", it's not a
> lot compared to the distance that rear panniers are below and to the rear
> of the saddle.
>
on a bike with out rider yes, but a heavily panniered bike will have a
rider when moving, and is likely to be a lot heaver, higher and more
forward, reduceing the benfit of the paniers. with regard to endos
> >>You're just clinging to purely psychosomatic ideas of brake power. It
> >>won't wash; and particularly it won't wash with anyone familiar with
> >>tandem applications, where you actually _can_ produce differences in brake
> >>power.
> >try taking a bike up and down steep hills good 30%
>
> When the gradient gets steep enough, the available braking before endo is
> small regardless of bottom position. That's one reason it's so blindingly
> obvious you're taking rubbish; you're picking the worse case for a brake
> to demonstrate supposedly superior power.
i'm not i'm pointing out that it is possible to counter the endo and
that riding up and down steep hills doesn't not mean that you end up
endoing every time you have to do a emergecy brake.
>
> >shift your weight around by that i don't mean your bottom as you put it
>
> Yes, you do. Your hands won't move; your shoulders won't get any further
> from the handlebars than they are with straight arms, although they will
> drop a bit. Your feet aren't going anywhere. The bottom is exactly the
> part that moves a lot.
on a mountain bike your shoulder will be above and just behind the
handle bars, you can move your shoulder to just above the saddle very
few hills if any would need such a move. your hands and feet stay put
but you can mover your trunk in a ark down and behind. which puts a lot
of weight lower down and rear.
roger
--
www.rogermerriman.com