Re: Brake Piece

["Joe Zaccaria" <jzaccaria@xxxxxxxxxxxxxx>]

Paul,

There are some basic laws of physics that apply here.  First if there was a
size mismatch between the master and slave cylinders the brakes would never
work properly whether or not the pads were worn.  You see one of the great
benefits of the disc brake caliper system is that they are self adjusting.
What this means is simply that as the pads wear, the calipers retain a bit
more fluid so the volume of fluid under pressure required to apply the
brakes never changes.  Therefore the concept of the brakes being less
effective when the pads have worn is an incorrect one.

If you look closely at the reservoir/master cylinder relationship, the
outlet of the reservoir is even with and in some circumstances lower than
the inlet of the master.  In addition, when the bikes came from the factory
the hose connecting the reservoir and master cylinder in some cases was
kinked.  Now bear in mind that the master cylinder is nothing more complex
than a simple lever pump, its effectiveness is directly related to the
delivery of fluid to its suction port.  Any restriction will cause reduced
or inconsistant performance.  Therefore raising the reservoir increases the
fluid pressure at the inlet of the master cylinder ensuring that only fluid
will be delivered to the caliper.

That's it in a nutshell.  I could go into greater detail if you like but
unless you have insomnia I'll refrain.

Zac
 ------------------------------------------------------------
 Free Web Email & Filter Enhancements.
 http://www.freewebemail.com/filtertools/
 ------------------------------------------------------------
- ----- Original Message -----
From: "Paul Fox" <pgf@xxxxxxxxxxxxxxxxxxxx>
To: <ST@xxxxxxxxxxxxxx>
Sent: Monday, February 12, 2001 12:39 PM
Subject: Re: Brake Piece


> re: fixing the mushy brakes by raising the reservoir -- i thought the
> problem with the brakes was a mismatch in the sizes of the master
> and slave cylinders, so that after the pads were worn, the lever could
> no longer move enough fluid to properly apply the pads.  if this is
> the case, i don't understand what raising the the reservoir does.  am
> i incorrect?  can anyone explain what the height change accomplishes?
>
> paul
> =---------------------
>   paul fox, pgf@xxxxxxxxxxxxxxxxxxxx (arlington, ma, where it's 25.3
degrees)
>
>      *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *
*
>       The ST/RS Mailing list is sponsored by Jack Lilley Ltd.
>           http://www.TriumphNet.com/st/lilley for more info
>    http://www.TriumphNet.com/st for ST, RS and Mailing List info


     *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *   *
      The ST/RS Mailing list is sponsored by Jack Lilley Ltd.
          http://www.TriumphNet.com/st/lilley for more info
   http://www.TriumphNet.com/st for ST, RS and Mailing List info

=-=-=-= Next Message =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=