Page 1 of 4
digest number 1477
Posted: Sun Jun 24, 2001 12:10 pm
by Jsherlockholmz@aol.com
In a message dated 6/23/01 7:11:13 PM Central Daylight Time,
DSN_klr650@yahoogroups.com writes:
>>
I hate to be the fly in the soup, but I disagree with the statement that
braided steel lines will not enhance stopping power. The inner Teflon lining,
and the hard carcass of the steel lines will increase brake performance. Look
at it this way. With the stock line, you have soft rubber, so some of the
energy that you created when you depressed the brake lever is used up flexing
and expanding the rubber lines. When you change to Teflon/steel lines, that
flex is reduced to an immeasurable amount. This allows almost all the energy
that you created when depressing the brake lever to be spent on pressing the
brake piston against the pads/disc instead. This will result in some amount
of increased braking power. I have tested this theory with my bike. I went to
a school parking lot, rode the bike with stock lines and proceeded to try a
controlled panic stop from 35 mph. After changing to Galfer lines, I retried
the experiment. My bike stopped a full car width quicker than with the stock
lines. I then added Galfer pads. Did the test again, and increased my
stopping power again. This time the bike stopped a car width and a half
quicker than stock. To me, that could mean the difference between life and
extreme pain, or even death. Stainless lines and higher grade pads do
increase your brakes performance. I recommend that anyone riding a KLR get
them. In fact, I recommend that the manufacturers start making them a stock
item on all bikes, this is a safety issue.
Just my $.03
Jim Sherlock
Austin, Texas
digest number 1477
Posted: Mon Jun 25, 2001 12:16 pm
by RM
On Sun, 24 Jun 2001 Jsherlockholmz@... wrote:
>and the hard carcass of the steel lines will increase brake performance.
>Look at it this way. With the stock line, you have soft rubber, so some
>of the energy that you created when you depressed the brake lever is
>used up flexing and expanding the rubber lines. When you change to
>Teflon/steel lines, that flex is reduced to an immeasurable amount. This
>allows almost all the energy that you created when depressing the brake
>lever to be spent on pressing the brake piston against the pads/disc
>instead.
I'm not a fluid engineer, but my line of thinking is that "x" lever force
will produce "y" line pressure which results in "z" braking force. The
expansion of the OEM brake line will affect the *volume* of fluid used,
but not the line pressure for a given lever force. The only way that a
line could change the relationship is if you can squeeze hard enough to
bottom the lever out against the grip.
RM
digest number 1477
Posted: Mon Jun 25, 2001 12:55 pm
by Barry Levine
"X" lever force will produce "Y" line pressure which will produce "Z" braking force. Well, that would be true if the volume of fluid "in the line" did not increase. Look at it in this manner:
Assume you had a child's balloon with two open ends. Connect one end to the master cylinder and the other end to the disc brake. Now squeeze the lever and watch the balloon expand. Do you really think the brakes are being applied with -any- measurable force at all? All the pressure on the lever is being used to expand the balloon with brake fluid. Why? Because the balloon is the part of the system with the least resistance to the pressure. Accordingly, substitute steel-braided lines that do not expand and all the pressure in the system goes to the caliper. *Presto*
Hope this helps.
Barry
--- In DSN_klr650@y..., RM wrote:
>
> On Sun, 24 Jun 2001 Jsherlockholmz@a... wrote:
>
> I'm not a fluid engineer, but my line of thinking is that "x" lever force
> will produce "y" line pressure which results in "z" braking force. The
> expansion of the OEM brake line will affect the *volume* of fluid used,
> but not the line pressure for a given lever force. The only way that a
> line could change the relationship is if you can squeeze hard enough to
> bottom the lever out against the grip.
>
> RM
digest number 1477
Posted: Mon Jun 25, 2001 1:11 pm
by Jim Jackson
I'm not an engineer at all but it seems to me there is a 'feel' and time
factor here as well. If you pull the lever in till you reach your desired
braking force, the line will still be expanding and therefore decreasing the
volume/pressure inside so that in order to keep the same braking force you
must pull the lever in farther thus applying more pressure, expanding the
line more and so forth in a decreasing curve. Does this make any sense?
Jim Jackson II
A13 "Gonzo" (still no takers?)
Baltimore MD
----Original Message Follows----
From: RM
CC: DSN_klr650@yahoogroups.com>
Subject: Re: [DSN_klr650] Digest Number 1477
Date: Mon, 25 Jun 2001 12:15:02 -0500 (CDT)
I'm not a fluid engineer, but my line of thinking is that "x" lever force
will produce "y" line pressure which results in "z" braking force. The
expansion of the OEM brake line will affect the *volume* of fluid used,
but not the line pressure for a given lever force. The only way that a
line could change the relationship is if you can squeeze hard enough to
bottom the lever out against the grip.
RM
_________________________________________________________________
Get your FREE download of MSN Explorer at
http://explorer.msn.com
digest number 1477
Posted: Mon Jun 25, 2001 9:13 pm
by Marc Illsley Clarke
Well, I am an engineer with more than a little physics background, so I'll throw my 2 in. I agree with Krock's explanations 100%. Nonetheless, I measured that my KLR650 stopped in 25% less distance after I put SS brake lines on. I believe the fresh clean Bel-Ray brake fluid I put in when I changed the lines made a huge difference in how much pressure was transmitted to the brake's piston rather than being absorbed in moisture contaminated compressible old brake fluid. I believe that the SS brake lones greatly improve the feel of the brake lever so I can apply more braking force sooner.
-- Marc, KLR650 A12, Loveland, Colorado, USA
"Jim Jackson" wrote:
__________
>I'm not an engineer at all but it seems to me there is a 'feel' and time
>factor here as well. If you pull the lever in till you reach your desired
>braking force, the line will still be expanding and therefore decreasing the
>volume/pressure inside so that in order to keep the same braking force you
>must pull the lever in farther thus applying more pressure, expanding the
>line more and so forth in a decreasing curve. Does this make any sense?
>
>Jim Jackson II
>A13 "Gonzo" (still no takers?)
>Baltimore MD
>
>
>
>----Original Message Follows----
>From: RM
>CC: DSN_klr650@yahoogroups.com>
>Subject: Re: [DSN_klr650] Digest Number 1477
>Date: Mon, 25 Jun 2001 12:15:02 -0500 (CDT)
>
>
>I'm not a fluid engineer, but my line of thinking is that "x" lever force
>will produce "y" line pressure which results in "z" braking force. The
>expansion of the OEM brake line will affect the *volume* of fluid used,
>but not the line pressure for a given lever force. The only way that a
>line could change the relationship is if you can squeeze hard enough to
>bottom the lever out against the grip.
>
>RM
>
>
-- Marc
Marc Illsley Clarke
mailto:marcclarke@...
digest number 1477
Posted: Tue Jun 26, 2001 8:01 am
by debbie@carrabassett.net
You all are forgetting something, the reason why braking is improved
is because when I picked up the bike brand new I could squeeze the
front brake all the way to the handlebar and wished it would go
further. After putting a braided line on I could apply the brakes as
hard as I wanted and would never go all the way to the bar.
John
--- In DSN_klr650@y..., "Jim Jackson" wrote:
> I'm not an engineer at all but it seems to me there is a 'feel' and
time
> factor here as well. If you pull the lever in till you reach your
desired
> braking force, the line will still be expanding and therefore
decreasing the
> volume/pressure inside so that in order to keep the same braking
force you
> must pull the lever in farther thus applying more pressure,
expanding the
> line more and so forth in a decreasing curve. Does this make any
sense?
>
> Jim Jackson II
> A13 "Gonzo" (still no takers?)
> Baltimore MD
>
>
>
> ----Original Message Follows----
> From: RM
> CC:
> Subject: Re: [DSN_klr650] Digest Number 1477
> Date: Mon, 25 Jun 2001 12:15:02 -0500 (CDT)
>
>
> I'm not a fluid engineer, but my line of thinking is that "x" lever
force
> will produce "y" line pressure which results in "z" braking force.
The
> expansion of the OEM brake line will affect the *volume* of fluid
used,
> but not the line pressure for a given lever force. The only way
that a
> line could change the relationship is if you can squeeze hard
enough to
> bottom the lever out against the grip.
>
> RM
>
>
> _________________________________________________________________
> Get your FREE download of MSN Explorer at
http://explorer.msn.com
digest number 1477
Posted: Tue Jun 26, 2001 12:16 pm
by Riley Harlton
RM wrote:
> On Sun, 24 Jun 2001 Jsherlockholmz@... wrote:
>
> >and the hard carcass of the steel lines will increase brake performance.
> >Look at it this way. With the stock line, you have soft rubber, so some
> >of the energy that you created when you depressed the brake lever is
> >used up flexing and expanding the rubber lines. When you change to
> >Teflon/steel lines, that flex is reduced to an immeasurable amount. This
> >allows almost all the energy that you created when depressing the brake
> >lever to be spent on pressing the brake piston against the pads/disc
> >instead.
>
> I'm not a fluid engineer, but my line of thinking is that "x" lever force
> will produce "y" line pressure which results in "z" braking force. The
> expansion of the OEM brake line will affect the *volume* of fluid used,
> but not the line pressure for a given lever force. The only way that a
> line could change the relationship is if you can squeeze hard enough to
> bottom the lever out against the grip.
>
> RM
I recently made the change or SS lines as well. It not sure what the physics
behind it are, all I know is that no matter how hard I squeezed with the old
rubber lines it never stopped like it does know. With old lines there was a
lot less initial bite. The more you squeezed the old line the more it
bulged. The more I squeeze now the more I stop.
Riley
A15
digest number 1477
Posted: Tue Jun 26, 2001 7:50 pm
by Jim & Shannon Morehead
Marc,
Compressible liquids??? I can't think of any.
Jim
----- Original Message -----
From: "Marc Illsley Clarke"
To: "Jim Jackson" ; DSN_klr650@yahoogroups.com>
Sent: Monday, June 25, 2001 9:12 PM
Subject: Re: [DSN_klr650] Digest Number 1477
> Well, I am an engineer with more than a little physics background, so I'll
throw my 2 in. I agree with Krock's explanations 100%. Nonetheless, I
measured that my KLR650 stopped in 25% less distance after I put SS brake
lines on. I believe the fresh clean Bel-Ray brake fluid I put in when I
changed the lines made a huge difference in how much pressure was
transmitted to the brake's piston rather than being absorbed in moisture
contaminated compressible old brake fluid. I believe that the SS brake
lones greatly improve the feel of the brake lever so I can apply more
braking force sooner.
>
> -- Marc, KLR650 A12, Loveland, Colorado, USA
>
> "Jim Jackson" wrote:
> __________
> >I'm not an engineer at all but it seems to me there is a 'feel' and time
> >factor here as well. If you pull the lever in till you reach your desired
> >braking force, the line will still be expanding and therefore decreasing
the
> >volume/pressure inside so that in order to keep the same braking force
you
> >must pull the lever in farther thus applying more pressure, expanding the
> >line more and so forth in a decreasing curve. Does this make any sense?
> >
> >Jim Jackson II
> >A13 "Gonzo" (still no takers?)
> >Baltimore MD
> >
> >
> >
> >----Original Message Follows----
> >From: RM
> >CC: DSN_klr650@yahoogroups.com>
> >Subject: Re: [DSN_klr650] Digest Number 1477
> >Date: Mon, 25 Jun 2001 12:15:02 -0500 (CDT)
> >
> >
> >I'm not a fluid engineer, but my line of thinking is that "x" lever force
> >will produce "y" line pressure which results in "z" braking force. The
> >expansion of the OEM brake line will affect the *volume* of fluid used,
> >but not the line pressure for a given lever force. The only way that a
> >line could change the relationship is if you can squeeze hard enough to
> >bottom the lever out against the grip.
> >
> >RM
> >
> >
>
> -- Marc
>
> Marc Illsley Clarke
> mailto:marcclarke@...
>
> Visit the KLR650 archives at
>
http://www.listquest.com/lq/search.html?ln=klr650
>
> Post message:
DSN_klr650@yahoogroups.com
> Subscribe:
DSN_klr650-subscribe@yahoogroups.com
> Unsubscribe:
DSN_klr650-unsubscribe@yahoogroups.com
> List owner:
DSN_klr650-owner@yahoogroups.com
>
> Support Dual Sport News by subscribing at:
>
http://www.dualsportnews.com
>
> Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
>
>
digest number 1477
Posted: Tue Jun 26, 2001 11:25 pm
by Marc Illsley Clarke
Make that "Krok's". Sorry, Chris.
-- Marc, KLR650 A12, Loveland, Colorado, USA
-- Marc
Marc Illsley Clarke
mailto:marcclarke@...
digest number 1477
Posted: Wed Jun 27, 2001 7:56 am
by Ted Palmer
Jim Morehead wrote:
> Marc,
> Compressible liquids??? I can't think of any.
Everything is compressible to some extent, more or less.
IIRC, one of the concerns that racers had with the then-new silicone
brake fluid was that it was _slightly_ more compressible than the
polyglycol stuff.
I notice that silicone fluid still hasn't taken over from polyglycol.
Mister_T