if you wanted maximum braking, where would you sit?

mexico?

Rick Onanian wrote:
wrote:
Rick Onanian wrote:
The unladen MTB has less inertia for the brakes to stop, so given
that CoG, can probably stop in a shorter distance.
No, that's not correct. The maximum braking deceleration is a function of
the CoG position, not the maximum braking force or amount of work done.
So, no matter how much you load a bike, if it's got the same CoG

Any CoG on a given line that passes through the front contact point.

then it can stop in the same distance? How far can you stretch that
effect?

Until the limiting factor is a loss of front wheel traction or inadequate
brakes. Normally, of course, the argument here is that "all brakes are
equally powerful"; that is because for most bicycles the forward tipover
point (or the loss of traction, for knobbly tyres) always intervenes
before the brake is not actually capable of exerting sufficient force
(where the brake is competently designed and adjusted); but you'll note
that Chalo Cholina has had to design special brakes to avoid this factor.
--
David Damerell Kill the tomato!

Mark Hickey:

While the front shock
is compressing, the rear wheel will have a bit more weight on it which
would help make up some of the difference, but still the end result is
that there will be a very brief period where a front shock will delay
the onset of "full braking".

It looks likely though that this will only happen if the weight on the
front fork is too light to start with, before braking; that is, the
braking force from the front wheel will only benefit from weight
transfer from the rear if the front wheel is on the verge of lifting or
skidding at the start of braking. It will be interesting to see what
maximum pre-braking loads the front wheel needs to have in order to
start skidding upon braking, IF there is no weight transfer from the
rear. This obviously will depend on rider weight and speed.

David Damerell wrote:

that is because for most bicycles the forward tipover
point (or the loss of traction, for knobbly tyres) always intervenes
before the brake is not actually capable of exerting sufficient force
(where the brake is competently designed and adjusted); but you'll note
that Chalo Cholina has had to design special brakes to avoid this factor.

And I need them now more than ever; because as of my last weighing, I
have crossed the border into the land of the 400 pounders! I have a
difficult time believing it myself. No wonder these steep Seattle
hills seem so merciless!

I took my drum-braked rain bike "on holiday" to Austin, Texas
recently, where I reacquainted myself with two things: First, that
the hills there are actually pleasant to ride on, being either gently
sloped or very short; and second, that even on gentle downhills a big
double handful of drum brakes is woefully inadequate to stop my
ponderous mass in a reasonable distance.

Chalo Colina

On 16 Jan 2004 15:10:38 -0800, (Chalo)
wrote:
sloped or very short; and second, that even on gentle downhills a big
double handful of drum brakes is woefully inadequate to stop my
ponderous mass in a reasonable distance.

Is it possible to use drum brakes AND V-brakes together? Possibly
using a cable Y-adapter or some such; and definitely using a lot of
force on the brake levers.

I guess, at least, you're able to get useful braking from the rear
wheel.

Chalo Colina
--
Rick Onanian

Rick Onanian wrote:
On 16 Jan 2004 15:10:38 -0800, (Chalo) wrote:
sloped or very short; and second, that even on gentle downhills a big
double handful of drum brakes is woefully inadequate to stop my
ponderous mass in a reasonable distance.
Is it possible to use drum brakes AND V-brakes together? Possibly using
a cable Y-adapter or some such; and definitely using a lot of force on
the brake levers.
I guess, at least, you're able to get useful braking from the
rear wheel.
Chalo Colina
--
Rick Onanian


Because of tandem's greater rider/bike weight their greater weight
there are special tandem bike levers pulling two cables

http://www.gaerlan.com/bikeparts/par...kes/brakes.htm

See the diatech levers


-

Rick Onanian wrote:
On Fri, 09 Jan 2004 10:52:59 -0500, Rick Onanian
wrote:

wrote:

My trike [2] has two front brakes (Avid mechanical disc on each wheel -
one lever for each brake) and no rear brake. Stopping quickly takes as

Wow! Cool...fail-safe steering.


Nevermind; I just looked at the picture, and it was the ONLY
steering.

Okay...Wow! Cool...integrated steering.

Okay, on a second look, I think I see spindles and control arms. Do
you steer with the brakes, with the front wheels, or with the rear
wheel? What control do you operate to steer? Do you steer with the
handlebars, which then aim the front wheels through control arms?
--
Rick Onanian

Here are some pictures of my Earth Cycles Dragonflyer (if the link is
working).
http://www.ihpva.org/incoming/2002/Dragonflyer/.

Tom Sherman - Quad Cities

Rick Onanian wrote:

Is it possible to use drum brakes AND V-brakes together? Possibly
using a cable Y-adapter or some such; and definitely using a lot of
force on the brake levers....

If the dropout spacing is great enough, an Arai drag brake could be used
on a rear wheel in conjunction with a rim brake (found on several
commercial tandems).

I rode stoker once on a Bike Friday Tandem Twos-Day that had V-brakes
and a front drum brake controlled with a Shimano bar-end shifter.

Theoretically, a hydraulic rim brake and a hydraulic disc brake could be
run from the same master cylinder and brake lever.

Tom Sherman - Quad Cities

meb wrote:



Because of tandem's greater rider/bike weight their greater weight
there
are special tandem bike levers pulling two cables


http://www.gaerlan.com/bikeparts/par...kes/brakes.htm

See the diatech
levers



-



This is how all cycling forums posts look like to my newsreader,
MT-Newswatcher. Can anyone suggest a fix?

In response to meb: The double-cable levers have nothing to do with the
tandem's weight. Their pupose is to allow a third brake, needed on many
tandems ridden in hilly areas not to stop but to scrub off speed without
thermally overloading the rims and tires.

--
Ted Bennett
Portland OR

(Chalo) wrote in message om...
David Damerell wrote:

that is because for most bicycles the forward tipover
point (or the loss of traction, for knobbly tyres) always intervenes
before the brake is not actually capable of exerting sufficient force
(where the brake is competently designed and adjusted); but you'll note
that Chalo Cholina has had to design special brakes to avoid this factor.

And I need them now more than ever; because as of my last weighing, I
have crossed the border into the land of the 400 pounders! I have a
difficult time believing it myself. No wonder these steep Seattle
hills seem so merciless!

I took my drum-braked rain bike "on holiday" to Austin, Texas
recently, where I reacquainted myself with two things: First, that
the hills there are actually pleasant to ride on, being either gently
sloped or very short; and second, that even on gentle downhills a big
double handful of drum brakes is woefully inadequate to stop my
ponderous mass in a reasonable distance.

Chalo Colina

Dear Chalo,

Here are the special brakes that you built and that
David mentioned:

http://home.comcast.net/~carlfogel/d.../red_brake.JPG
http://home.comcast.net/~carlfogel/d...d/redfront.JPG

Carl Fogel