disc brakes for road bikes?

Stefan said:

I was chatting with my riding buddies this last weekend
and we started a discussion on why road bike companies
have not adopted disc brakes for road bikes? It seems to
me that the greater stopping power would be a good idea,
especially for hilly riding. I'm curious as to what you
all think? Should road bike disc brakes be created and how
come they don't exist today?

Disc specific forks are available for road bikes - I saw a
number of cyclo-cross bikes with discs this year, though
only front, not rear. For road use, I dont think there will
be much benefit to be had, discs excel in wet and muddy
conditions, but for their benefits, you have the penalty of
the extra weight to carry, of which roadies tend to not want
- if something is 10g lighter than a competitior, then
people buy the 10g lighter product. I could see a benefit in
touring bikes, but if you are going on a tour, having to
carry spares would be a pain, as although easily got mail-
order, many local bike shops will not keep the disc spares
in stock, whereas they will almost certainly have spares for
caliper brakes. Alan.

--
To reply by e-mail, change the ' + ' to 'plus'.
dvatc.co.ukdvatc.co.ukOpen ↗ - Off-road cycling in the North
Midlands.

[email hidden] (Stefan) wrote in news:ac070dd8.0405171024.c6723b1
@posting.google.com:

Quoted message said:

I was chatting with my riding buddies this last weekend
and we started a discussion on why road bike companies
have not adopted disc brakes for road bikes? It seems to
me that the greater stopping power would be a good idea,
especially for hilly riding.

Some tandems have disc brakes. Most roadies probably don't
want to pay the weight penalty. Mountain bikers like disc
brakes because the work in muddy conditions, but road bikers
don't often have that problem.

"Stefan" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Hi all,

I was chatting with my riding buddies this last weekend
and we started a discussion on why road bike companies
have not adopted disc brakes for road bikes? It seems to
me that the greater stopping power would be a good idea,
especially for hilly riding.

I'm curious as to what you all think? Should road
bike disc brakes be created and how come they don't
exist today?

Cheers, Stefan

They do exist:
avidbike.comcps2 2 road.htmlOpen ↗

They're not hugely popular because the value, if not
necessity, of disc brakes has been largely overstated.
Unless you're doing very aggressive mountain bike riding
caliper brakes work fine (and, I'm a pretty aggressive
mountain bike rider). Also, high-performance roadies, the
sort who would benefit most from discs, are notorious gram-
counters and discs are much heavier than caliper brakes.

Now that that is out in the open, I imagine all sorts of
arguments will appear for and against discs. That's not my
intention, so don't bother.

Chris

Quoted post said:

Originally posted by Stefan
Hi all,

I was chatting with my riding buddies this last weekend and
we started a discussion on why road bike companies have not
adopted disc brakes for road bikes? It seems to me that the
greater stopping power would be a good idea, especially for
hilly riding.

I'm curious as to what you all think? Should road bike disc
brakes be created and how come they don't exist today?

Cheers, Stefan

Current big detractions:
1. Weight.
2. Fork and frame attachements and appropriate structural and safety considerations.
3. Weaker wheels due to decreased spoke support angles.
4. Many different configurations of discs, calipers, mechanical and hydraulics, etc. (Most don't work well with Brifters)
5. Interference with rack and fender mounting also seem to make them tough to use for touring.

Superior stopping power and no rim brake track wear are some of the good things. Rim heating goes too.

There is a future for them. Sheldon Brown wrote an article for Adventure Cycling magazine that covers many of the issues.
I was planning to provide a link to the article, but it isn't on the site yet.

Stefan Bolka said:

I was chatting with my riding buddies this last weekend
and we started a discussion on why road bike companies
have not adopted disc brakes for road bikes? It seems to
me that the greater stopping power would be a good idea,
especially for hilly riding.

Quoted message said:

I'm curious as to what you all think? Should road
bike disc brakes be created and how come they don't
exist today?

You assume there is a lack of stopping power in your
opening statement. I think you need to substantiate that
first. Secondly, road racing bicycles are the way they are
mainly because changing to discs adds complexity, weight
and is not easily integrated with the controls currently in
use. People have been working on that and have not made any
good progress.

If they were actually better, you can bet they wouldn't be
on the sidelines. If they do come into play some day, it
will probably be mainly through people like yourself who
favor them unquestionably. That's how we got higher
mechanical dual pivot brakes. There were enough avocational
bicyclists, who make up the bulk of the retail market, who
did not have enough strength to use the previous brakes with
a 4:1 ratio. The same goes for frame fit Silca tire pumps
with which people regularly broke off valve stems and failed
to achieve ridable pressure. Brake lever shifting was
introduced in response to people who could not pedal wile
riding one handed... which made shifting awkwardly
difficult.

Jobst Brandt [email hidden]

In article <[email hidden]>,

Stefan said:

Hi all,

I was chatting with my riding buddies this last weekend and
we started a discussion on why road bike companies have not
adopted disc brakes for road bikes? It seems to me that the
greater stopping power would be a good idea, especially for
hilly riding.

With a decent braking surface (naked aluminum without
anodizing), road brakes have enough power to lift the rear
wheel off the ground. More braking force isn't necessary.
The mechanical advantage provided by dual pivot brakes makes
this easy to do from on top of the brake hoods - more isn't
necessarry. That leaves contamination - except in heavy
slush/sleet, you don't get enough gunk on the brakes, and
few roadies ride in that situation.

Quoted message said:

I'm curious as to what you all think? Should road bike disc
brakes be created and how come they don't exist today?

A dual pivot front caliper and single pivot rear are ideal
from a performance/weight standpoint.
--
<a href="poohsticks.orgdrewOpen ↗">Home Page</a

In article <[email hidden]>,
[email hidden] says...

Quoted message said:

Hi all, I was chatting with my riding buddies this last
weekend and we started a discussion on why road bike
companies have not adopted disc brakes for road bikes? It
seems to me that the greater stopping power would be a good
idea, especially for hilly riding. I'm curious as to what
you all think? Should road bike disc brakes be created and
how come they don't exist today?

Do you find your current brakes lacking in stopping power? I
sure don't. There is also the extra weight of the disk and
caliper as compared to the current brake standards. Having
to build your front wheel offset to accomodate the brake
rotor is going to weaken the wheel. You should also see the
other discussion on wheel ejectiions caused by disc brakes.
-----------------
Alex

Stefan said:

Hi all,

I was chatting with my riding buddies this last weekend
and we started a discussion on why road bike companies
have not adopted disc brakes for road bikes? It seems to
me that the greater stopping power would be a good idea,
especially for hilly riding.

I'm curious as to what you all think? Should road
bike disc brakes be created and how come they don't
exist today?

There isn't really anything wrong with the current method;
it's light, fairly cheap and uses a huge disc - the wheel
rim. Road forks are also quite slender and would need to be
beefed up considerably for a hub brake of any kind. Some
touring bikes - which are increasingly MTB-derived - have
discs, but they're quite heavily built.

MTBs suffer more from bent wheels and sticky mud, and even
there the case for discs is far from clear.

(Stefan) said:

I was chatting with my riding buddies this last weekend
and we started a discussion on why road bike companies
have not adopted disc brakes for road bikes? It seems to
me that the greater stopping power would be a good idea,
especially for hilly riding.

I'm curious as to what you all think? Should road
bike disc brakes be created and how come they don't
exist today?

Well, to be pedantic about it caliper brakes are already
disk brakes. ;-) Disk brakes are being offered on some road
bikes, at least on some tandems. At this point they weigh
more and there are other concerns about the current design.
There's a whole 'nother thread going on about this right
now in rec.bikes.tech and there have been several threads
about some of the other concerns- such as front wheel
ejection from braking forces- if you care to check the
archives at Google.

I've never had a problem with standard rim brakes and I see
no advantage to disk brakes for me. Some have pointed out
the issue with rim heating when braking is prolonged, such
as when riding in mountains. I live in flat-to-rolling
terrain and have never encountered this issue. I rode in the
Alps for 10 days in 2002 and while my rims got warm they
never overheated. Other people with more experience than I
in the mountains have reported significant issues. If I was
tandeming in the mountains, I could see some value to disk
brakes regarding the heating issue. The odds of this
happening for me are pretty slim, my wife hates climbing
with a bike even though she loves to backpack. There may be
some concerns about the disks' ability to tolerate heating
without distorting (see the other thread).

Some report that disk brakes offer a smoother and more
easily modulated feel to the brake lever. I found the
opposite, that the brakes were grabby, but that was a couple
of years ago and perhaps those brakes weren't set up right
or the technology has improved.

Tim McNamara said:

I've never had a problem with standard rim brakes and I
see no advantage to disk brakes for me.

my cyclocross/touring bike has a front disc brake & that was
primarily to fix a fork shudder problem (it did that quite
nicely) which is another way of saying i probably wouldn't
have done it otherwise.

that said ..

Quoted message said:

Some have pointed out the issue with rim heating when
braking is prolonged, such as when riding in mountains. I
live in flat-to-rolling terrain and have never encountered
this issue. I rode in the Alps for 10 days in 2002 and
while my rims got warm they never overheated. Other people
with more experience than I in the mountains have reported
significant issues.

they are definitely better w/r/t heating. but a rim brake
can take a fair bit of heating .. it takes a lot of steep,
very technical descents to make it happen. i'm in the
mountains and it's pretty rare for me that it gets that bad.
but it is nice not to have to worry (except of course that
now you all have me watching my q/r ;-) ..

Quoted message said:

If I was tandeming in the mountains, I could see some
value to disk brakes regarding the heating issue.

[snip]

Quoted message said:

There may be some concerns about the disks' ability to
tolerate heating without distorting (see the other
thread).

well, that'd probably be well after a similiar rim brake
setup was out of commission, anyway.

Quoted message said:

Some report that disk brakes offer a smoother and more
easily modulated feel to the brake lever. I found the
opposite, that the brakes were grabby, but that was a
couple of years ago and perhaps those brakes weren't set
up right or the technology has improved.

mine modulate just fine and they are certainly not grabby.
they "feel" different (and i believe me i know, my rear is
still a canti) but there's nothing in the least
objectionable about them (avid mech).

& tim, they kick ass in the snow ;-)
--
david reuteler [email hidden]

Quoted message said:

why road bike companies have not adopted disc brakes for
road bikes?

They have no motive to do so.

Quoted message said:

It seems to me that the greater stopping power would be a
good idea, especially for hilly riding.

Disks have stopping power greater than good rim brakes only
in some circumstances: rain, mist, mud, hot-braking mountain
descent, and similar conditions to which most roadies do not
intentionally subject themselves. They wouldn't put up with
the additional weight, anyway.

(Stefan) said:

I was chatting with my riding buddies this last weekend
and we started a discussion on why road bike companies
have not adopted disc brakes for road bikes? It seems to
me that the greater stopping power would be a good idea,
especially for hilly riding.

I'm curious as to what you all think? Should road
bike disc brakes be created and how come they don't
exist today?

You assume that disc brakes are more powerful than rim
brakes. They are not. That is immaterial for most riders
anyway, who have more potential braking torque than they are
able to use regardless which type of brakes they employ.

The chief advantage of disc brakes is that they separate the
rims's structural duties from its braking duties. This
allows good braking to be maintained even if the rim is
contaminated or bent, which are not everyday concerns for
road cyclists.

The "feel" improvements attributed to disc brakes are
actually due to the hydraulics or fully-housed cables that
control them, and not to the discs themselves. There are
hydraulic rim brakes available, which offer similar
improvements in "feel" along with more maximum braking power
than discs can offer.

I use discs on a couple of my bikes, for the primary purpose
of allowing fatter tires than would otherwise be convenient
to install, and for the secondary purpose of eliminating rim
wear and its attendant filth resulting from wet riding. I do
not use them to get more or better braking than is available
from rim brakes, because they don't offer that.

Chalo Colina

"Chalo" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

[email hidden] (Stefan) wrote: I do not use them
to get more or better braking than is available from rim
brakes, because they don't offer that.

Really? I find a DISTINCT difference between Avid V-brakes
(SD 7) and Avid's cable-actuated disc brakes. I weigh
200lbs, so maybe it can be attributed to larger weights, but
overall the disc brakes are substantially more powerful than
rim brakes.

Jan

RE/

Quoted message said:

I'm curious as to what you all think? Should road bike disc
brakes be created and how come they don't exist today?

One recollection I have of my road bike was that it was kind
of scarey to ride in the rain.... So maybe I would have gone
for a front disc....
--
PeteCresswell

(Pete Cresswell) said:

RE/

Quoted message said:

I'm curious as to what you all think? Should road
bike disc brakes be created and how come they don't
exist today?

One recollection I have of my road bike was that it was
kind of scarey to ride in the rain.... So maybe I would
have gone for a front disc....

I've heard a lot of people complain that they feel their
brakes are useless in the rain. I have no problems at all
myself. I'm more concerned about reduced traction on the
road surface, because I can more easily lock my rim brakes
when they're wet!

Given that, how about another alternative for heavy weather
- roller brakes? They seem to be the ticket not for road
riding, but rather for all-weather commuting.

-Collin

Stefan Bolka said:

Quoted message said:

I was chatting with my riding buddies this last weekend
and we started a discussion on why road bike companies
have not adopted disc brakes for road bikes? It seems to
me that the greater stopping power would be a good idea,
especially for hilly riding.

Quoted message said:

I'm curious as to what you all think? Should road
bike disc brakes be created and how come they don't
exist today?

You assume there is a lack of stopping power in your
opening statement.

After riding a rainy half-century yesterday, I would have to
agree. It's been a long time since I rode a freewheeling
bike in wet conditions, and it was sometimes scary. Not
scary enough to keep me from hitting 42 mph on one of the
descents though! (A new record for my Thorn Raven
sheldonbrown.orgthrornOpen ↗.)

Quoted message said:

I think you need to substantiate that first. Secondly,
road racing bicycles are the way they are mainly because
changing to discs adds complexity, weight and is not
easily integrated with the controls currently in use.
People have been working on that and have not made any
good progress.

Not clear if Bolka is referring to _racing_ equipment when
he says "road" though that is often used as a synonym.

Quoted message said:

If they were actually better, you can bet they wouldn't be
on the sidelines. If they do come into play some day, it
will probably be mainly through people like yourself who
favor them unquestionably. That's how we got higher
mechanical dual pivot brakes. There were enough
avocational bicyclists, who make up the bulk of the retail
market, who did not have enough strength to use the
previous brakes with a 4:1 ratio. The same goes for frame
fit Silca tire pumps with which people regularly broke off
valve stems and failed to achieve ridable pressure. Brake
lever shifting was introduced in response to people who
could not pedal wile riding one handed... which made
shifting awkwardly difficult.

Yes, and in the automotive world, electric starters came
along 'cause effete drivers were too wussy to turn the crank
like a Real Man.

Then the synchromesh transmission was introduced for the
benefit of klutzes who couldn't manage to learn the simple
technique of double-clutching...and don't get me started
about safety glass, seatbelts and power steering!...

Sheldon "Those Were The Days...?" Brown +----------------------------------------------------------
+
| The people who live in a Golden Age usually go around |
| complaining how yellow everything looks. | -- Randall
| Jarrell |
+----------------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts Phone 617-244-
9772 FAX 617-244-1041 harriscyclery.comharriscyclery.comOpen ↗ Hard-to-find
parts shipped Worldwide captainbike.comcaptainbike.comOpen ↗
sheldonbrown.comsheldonbrown.comOpen ↗

Quoted message said:

Then the synchromesh transmission was introduced for the
benefit of klutzes who couldn't manage to learn the simple
technique of double-clutching...and don't get me started
about safety glass, seatbelts and power steering!...

Sheldon "Those Were The Days...?" Brown

Ever been to the workshop area of an old farm? All those
belts going every which-way with no protective covers...
yikes, I never looked hard enough, but I'm sure they must
have had an emergency saw stashed in a safe place just for
quick amputations...

--Mike-- (Who spent a fair amount of time on the
Grandparent's farm as a kid, and thought the workshop area
was really cool) Chain Reaction Bicycles
chainreactionbicycles.comchainreactionbicycles.comOpen ↗

In article <[email hidden]>, Sheldon Brown

Quoted message said:

After riding a rainy half-century yesterday, I would have
to agree. It's been a long time since I rode a
freewheeling bike in wet conditions, and it was sometimes
scary. Not scary enough to keep me from hitting 42 mph on
one of the descents though! (A new record for my Thorn
Raven sheldonbrown.orgthrornOpen ↗.)

This is better:

sheldonbrown.orgthornOpen ↗

luke

Mike Jacoubowsky said:

Quoted message said:

Then the synchromesh transmission was introduced for the
benefit of klutzes who couldn't manage to learn the
simple technique of double-clutching...and don't get me
started about safety glass, seatbelts and power
steering!...

Sheldon "Those Were The Days...?" Brown

Ever been to the workshop area of an old farm? All those
belts going every which-way with no protective covers...
yikes, I never looked hard enough, but I'm sure they must
have had an emergency saw stashed in a safe place just for
quick amputations...

--Mike-- (Who spent a fair amount of time on the
Grandparent's farm as a kid, and thought the workshop area
was really cool) Chain Reaction Bicycles
chainreactionbicycles.comchainreactionbicycles.comOpen ↗

Dear Mike,

Little need for emergency saws. The powered belts usually
pull the fingers and limbs into the pulleys at a brisk
enough pace to separate things just as effectively as gears,
chains, and other mechanical hazards.

You can confirm this by spending half an hour counting
fingers at a hardware or auto parts counter patronized by
farmers and ranchers. You'll meet a surprising number of nine-
fingered ladies, too.

Of course, they might all be penitent Yakuza members, but
the John Deere caps suggest otherwise.

Carl Fogel