Re: rear rim seems to rub

In article <vaidncGliJ07zKHanZ2dnUVZ_tyknZ2d@xxxxxxxxxxxxx>,
jim beam <spamvortex@xxxxxxxxxxxxxxx> wrote:
Luns Tee wrote:
In article <GOCdnY7kbLrAMaTanZ2dnUVZ_jmdnZ2d@xxxxxxxxxxxxx>,
jim beam <spamvortex@xxxxxxxxxxxxxxx> wrote:
Luns Tee wrote:
In article <oZWdnS6ivZi-fKranZ2dnUVZ_jCdnZ2d@xxxxxxxxxxxxx>,
jim beam <spamvortex@xxxxxxxxxxxxxxx> wrote:
If the ratio of the caliper as a whole is 2:1 as you say, the
force being transmitted across the rim is 200N. How is 100N on the cable
side of the Y arm, vs. 200N on the pad side of the Y arm an equilibrium?
"floating" of the rim. just like in the avid mechanical disk brake caliper.
Floating only means that the supposed 200N from the C arm pad
is carried through to the Y arm pad, but the question is of how the Y
arm is able to press 200N against this - this is implicit in the
question I pose. Repeating part of the question is not an answer to
the question. You still have not addressed the question of how a 1:1
lever can have forces on it in a 2:1 ratio yet be in equilbrium.
no, reconsider the avid disk caliper i mention. one pad is completely
fixed, but braking force is applied equally from both pads because the
disk floats. rims do the same.
The one-side-fixed caliper is not a valid analogy: a 1:1 lever
between the pad and cable clamp is not a fixed stop. If the Y arm were a
fixed stop, then it would not rotate on its pivot, and we're left with a
single-pivot brake. What is under discussion is dual-pivot brakes.
but luns, with respect, if the y-arm is fixed, you have exactly the same
braking as with the avid disk brake.

IF the y-arm is fixed, then I agree with the avid brake as a
model. However, you yourself have claimed that the Y arm is free to
pivot, independently of the C arm at that.

it can be compressed independently of the c-arm.


What makes the Y arm, that
is otherwise free to pivot, into a fixed stop?

application of pressure from the brake cable.

That is NOT a fixed stop. A freely pivoting 1:1 lever transmits
force from the pad through to force at the cable in a 1:1 ratio. So I
ask you one more time, with 100N of cable tension, if things are as
you say, how does 200N at the pads constitute an equilibrium?

-Luns
.

Relevant Pages

  • Re: rear rim seems to rub
    ... balance, and a 20kg weight on the other, the two are ... asking you how you think the Y arm can be in equilibrium. ... after the cable and pad have been accounted for. ... dual-pivot brake does not move the rim when it is applied. ...
    (rec.bicycles.tech)
  • Re: rear rim seems to rub
    ... jim beam wrote: ... side of the Y arm, vs. 200N on the pad side of the Y arm an equilibrium? ... lever can have forces on it in a 2:1 ratio yet be in equilbrium. ...
    (rec.bicycles.tech)
  • Re: rear rim seems to rub
    ... jim beam wrote: ... force being transmitted across the rim is 200N. ... side of the Y arm, vs. 200N on the pad side of the Y arm an equilibrium? ...
    (rec.bicycles.tech)
  • Re: rear rim seems to rub
    ... force being transmitted across the rim is 200N. ... side of the Y arm, vs. 200N on the pad side of the Y arm an equilibrium? ... just like in the avid mechanical disk brake caliper. ...
    (rec.bicycles.tech)
  • Re: rear rim seems to rub
    ... force being transmitted across the rim is 200N. ... side of the Y arm, vs. 200N on the pad side of the Y arm an equilibrium? ... just like in the avid mechanical disk brake caliper. ...
    (rec.bicycles.tech)